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Strategies for Sustainable Construction Using a Unique Rating System: A Case Study— Rebecca M. Oliva Priorities: Getting the Most From Your Capital Improvement Plan—Jason Destigter Wastewater Treatment Cost Reduction: Stabilizing Chlorine Demand in Wastewater Effluent— Charles Nichols, David Carr, Mark Lowenstine, and Craig Fuller
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Volume 67
ON THE COVER:
May 2015
Number 5
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Building Community Consensus for a Regional Supplier Patrick Lehman, Donald Ross, and Michael Condran Democratic governance requires consent of the governed. This is never truer than when forging a cooperative approach to regional water supplies owned and operated by different member governments and serving additional political entities. The success of the Peace River Manasota Regional Water Supply Authority (Authority) has rested upon its transparent governance, outreach to all parties, and most importantly, community support through a not-for-profit educational organization dedicated to extolling the benefits of regional water supplies. The Friends of Peace Water Inc. has been an essential element of the Authority’s regional governance success.
Authority Profile The Authority was created by interlocal agreement among four Florida counties—Charlotte, DeSoto, Manatee, and Sarasota—to ensure adequate, dependable, high-quality water supplies for a growing population of more than
900,000 in southwest Florida. By working within a regional consensus, the Authority has met the region’s water supply and created a robust and reliable system successfully meeting the challenges of completing a capital expansion program and constructing new infrastructure to expand treatment and interconnect the region’s major water supply systems. The Authority is a wholesale supplier of drinking water to its member governments. The agency is operated through revenue collected by water sales to its customers—the member counties and the City of North Port. The mission statement of the Authority is “to provide the region with a sufficient, high-quality drinking water supply that is reliable, sustainable, and protective of our resources, now and into the future.” The Authority was created thirty years ago in 1982. Through the initial decade of the Authority, the planning effort focused on interconnecting water systems. In 1991 the privately owned water utility serving Charlotte and DeSoto Counties and the North Port area of Sarasota County, General Development Utilities (GDU), went into
Peace River Manasota Regional Water Supply Authority location map.
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bankruptcy. The demise of GDU led to acquisition of the existing Peace River Facility located in DeSoto County and the existing transmission pipeline that provided service to the water systems within the three counties served by GDU. Through the 1990s the Authority planned for expansion of the Peace River Facility and extension of the transmission pipeline system to provide increased capacity to the existing water systems and to provide expanded water service to Charlotte, DeSoto, and Sarasota Counties. The first decade of the 2000s saw tremendous expansion of the Authority’s infrastructure as it progressed into a major operating utility. The Peace River Facility treatment capacity was expanded from 12 to 48 mil gal per day (mgd) and the regional transmission pipeline system was extended from 7 mi to over 65 mi of large diameter transmission pipelines.
Friends of Peace Water The not-for-profit, Friends of Peace Water Inc. (Friends) has been an essential element of this regional governance success. Organized by a group of local business leaders who recognized the value of a reliable water supply and its role in economic growth and prosperity, Friends advances educational opportunities for communities to learn about their water supply, the effects of human behavior on the supply, the furtherance of public education, and the maintenance of Florida’s water resources. Large, forward-looking infrastructure projects often stretch the imagination. They may seem unnecessary, or even wasteful, at the time they are planned. The budgets are large, and the public often fears that they are overblown. Cynics believe that the project is just a way for insiders to make big money or consider it a government boondoggle. It’s against these headwinds that elected officials make funding deci-
sions, often for benefits they will not see in their term in office. To provide balance against these fears and support for funding decisions, public support groups often spring up from infrastructure users to advocate for the projects with an organized voice. A number of states have support groups for transportation projects, including Florida. These groups are usually comprised of a core membership of corporate users who understand the economic benefits of infrastructure development. A grocery store chain in Florida, for instance, is a member of a group called Floridians for Better Transportation, and sees the benefit of road infrastructure to its distribution system. The Friends group was chartered to support opportunities for local communities to learn about their water supply. The founders believed that many people are so used to readily available, pure water from the tap that few understand what is required to keep the water flowing. Such public ignorance is a deterrent to prudent planning and development of water supplies, and Friends’ mission is to foster a better understanding in a variety of ways. Public Education Friends furthers its educational mission on two fronts. First, it hosts an annual educational event for elected officials, community leaders, citizens at large, and the media at the Authority’s Peace River Facility. In addition to facility tours, state political leaders address the importance of regional water supply development. Friends raises the funds to support the event with a catered barbeque that has become the hallmark of this traditional event. Being private and nongovernmental, Friends can collect and spend funds for events of this type that would be prohibited by a public agency. Friends’ education mission supports three themes: Continued on page 6
operative efforts and economies of scale of large alternative water supply projects. Friends promotes the Authority’s regional approach by seeking recognition from forward thinking organizations in Florida, such as 1000 Friends of Florida, Audubon of Florida, and the Collins Center for Sustainable Florida. Recognition by these organizations helps shore up the political consensus necessary for regional governance. Friends has prepared successful applications for recognition of good regional governance from these watchdog groups. Adam Putnam, Commissioner of the Florida Department of Agriculture and Consumer Services, attending the barbeque.
Continued from page 4 ! Regionalism for water resource development and distribution ! Environmental sustainability ! Managing competition among industrial, agricultural, and public supply demands Regionalism Water resources rarely respect political boundaries, and much time, energy, and money has been wasted in litigation by public users over rights to water supplies. Adopting a regional framework for water resource development helps diffuse the tensions among local jurisdictions about water use rights. Florida law provides for the creation of regional water supply authorities by interlocal agreement among local governments for the provision of wholesale water supply to locallyowned utilities. Friends supports, through education, the regional governance of the Authority. While not everyone agrees with all collective decisions of the Authority, all points of view are heard, and litigation is kept to a minimum. Friends recognizes that these internal workings deep in the machinery of government are rarely understood or appreciated by the constituents served, and it works to highlight and celebrate these efforts. Ultimately, the consumer pays for water, but through intergovernmental cooperation among the member governments, all consumers benefit through co-
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Environmental Sustainability There are many instances of conflicts between water supply demands and the environment, such as the current issue between agricultural allocations to California’s Central Valley and protection of the endangered delta smelt. While not as severe as the Central Valley issues, the Authority faces the same kind of issue with its withdrawals from the Peace River. Too much withdrawal at the wrong time would have an adverse impact on the Charlotte Harbor estuary downstream. The Authority has addressed environmental sustainability by building the storage capacity to allow it to provide a constant supply of water to its customers, while only withdrawing from the Peace River when scientists determine it is safe. The Authority’s investment in storage facilities represents a third of its investment at the Peace River Facil-
May 2015 • Florida Water Resources Journal
ity. In addition, the Authority supports an extensive monitoring program in the estuary to measure the effects, if any, of its withdrawals. Because these protective measures cost the consumers money that some may feel is unnecessary, Friends provides an educational event each year for the general public at the Peace River Facility to explain the issue and provide tours of the facilities, including its 6 bil gal aboveground reservoir. Managing Competition Friends believe that when sharing water resources, the economics of all users has to be considered in fair allocation. Urban users consume less water than agricultural and industrial users in Florida, yet need to meet higher standards for water quality. Agricultural and industrial users could easily be outbid for water if it were allocated by market pricing; therefore, rational allocation among these disparate users requires an understanding of the various constraints and a willingness to find an optimal solution for all users. Friends promotes the understanding required for managing competition through education at its annual public event at the Peace River Facility. Keynote speakers are invited from various sectors, including government, to address the larger regional picture in which public supply is a part. Speakers, such as the state commissioner of agriculture and the secretary of the Florida Department of Environmental Protection, have provided impetus to Friends’ message.
Collaborative Approach for Local Governments Because elected officials from each member government are responsive to the voters of their respective counties, Friends works to create a grass roots consensus among voters in the four counties that regional cooperation is, in the long term, best for the interests of all and has proven to be a catalyst within the business community for articulating the value of water. Water is vital to a growing economy. The promotion of the value of water to the public and political leadership is critical to assuring a reliable, sustainable, and affordable public water supply for the residents and businesses in the region. Friends has recognized the value of water and its need for economic growth and prosperity. The organization is instrumental in working with the public, local elected officials, and business leaders to further the understanding of the importance of a sustainable water supply for the state.
Friends of Peace Water Inc. roster board recognizing membership.
Peace River Off-Stream Reservoir.
Patrick Lehman is executive director of Peace River Manasota Regional Water Supply Authority in Lakewood Ranch; Donald Ross, is chair of Earth Balance in North Port; and Michael Condran is regional manager–water/wastewater services with Conestoga-Rovers & Associates in Tampa. !
F W R J
Strategies for Sustainable Construction Using a Unique Rating System: A Case Study Rebecca M. Oliva
T
he Envision™ sustainable infrastructure rating system is administered through the Institute for Sustainable Infrastructure (ISI) and designed to help users identify ways in which sustainable approaches can be used to plan, design, construct, and operate infrastructure projects. Applying this rating system to utility infrastructure, such as a water resource reclamation facility (WRRF), can provide owners, planners, managers, designers, and contractors with a practical, numerical measure of sustainability. Hillsborough County (County) is currently expanding its South County Advanced Wastewater Treatment Facility (AWTF) from 4.5 to 10 mil gal per day (mgd), a construction project that totals over $68 million. Although the project was not submitted to ISI for official verification and award, the rating system was applied to the construction phase in order to assess sustainability measures carried out during this particular phase of the project. The County retained three onsite resident observers, one of whom is credentialed by ISI as an Envision Sustainability Professional (ENV SP). The perspective from which this article was written is unique—18 months of full-time construction experience as a resident engineer on the job site, coupled with being an ENV SP and having knowledge of applying the rating system to other projects. This allows for the perfect marriage of construction knowledge and the rating system, with the benefit of identifying specific strategies that can be done to improve the sustainability of the project. This perspective leads to the ability to align the rating-system aspects with the dual nature of sustainability during construction. This article presents examples of how the rating system can be used during utility construction projects to improve sustainability performance. For example, effective coordination through the use of meetings and written plans reduces the chance of issues arising during scheduled plant shut-downs and helps resume reliable plant operations and service for customers. The rating system provides a practical measure of sustainability, making it easier to assess, manage, and improve the conditions of civil infrastructure and contribute to overall
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utility sustainability. This rating system has become increasingly recognized by project owners, planners, managers, and designers as an appropriate water infrastructure rating tool since its introduction in 2012. A description of, and the need for, this rating system are presented from various perspectives, and numerous strategies for sustainable construction through the case study example at the AWTF are described.
Sustainable Construction Defined In their book, Design for Sustainability, Ji and Plainiotis define sustainable construction as “a process that is environmentally responsible and resource-efficient throughout a building's life cycle: from siting to design, construction, operation, maintenance, renovation, and demolition. This requires close cooperation of the design team, the architects, the engineers, and the client at all project stages.” Even though they state that the process is through a building’s life cycle, this definition can also be applied to the life cycle of facilities and infrastructure, such as WRRFs, pipelines, and pump stations. Furthermore, this definition highlights the importance of cooperation among all parties involved with the project at all stages.
Need for a Sustainable Infrastructure Rating System The American Society of Civil Engineers (ASCE) assessed the conditions of 15 categories of civil infrastructure. To communicate the results of its study, ASCE produced a report card that states that the current condition of America’s infrastructure should receive a grade of D (poor condition). For the drinking water and wastewater categories, leaking pipelines and pump failures are examples contributing to this low grade. The ASCE estimates that a five-year investment of $2.2 trillion would bring America’s infrastructure grade to a B (good condition). It would be beneficial to have a rating system that covers these categories so that money for infrastructure projects is well spent.
Rebecca M. Oliva, P.E., ENV SP, is an environmental engineer with CDM Smith in Tampa.
Water professionals familiar with the Leadership in Energy and Environmental Design (LEED™) rating system recognize that it focuses on buildings and facilities. What LEED does not provide is a comprehensive system to evaluate the sustainability of civil infrastructure projects. Therefore, the Envision infrastructure sustainability rating system was developed by ISI in partnership with the Zofnass Program for Sustainable Infrastructure at the Harvard University Graduate School of Design. No other United States rating system covers all aspects of civil infrastructure, so Envision was developed, in part, to fill this gap.
The Envision Rating System This rating system has several components, including a self-assessment checklist, the rating tool, a credential program for individuals, a project evaluation and verification program, and a recognition program. The system is structured around five categories: quality of life, leadership, resource allocation, natural world, and climate and risk. The rating system’s guidance manual contains a table of point values, which shows the five categories and numerous credits (each row in the table is a credit). For the case study included here, specific strategies will be presented that show how these Envision sustainability goals, or credits, can be achieved during construction. Levels of achievement indicate how well a credit meets the criteria described in the guidance manual, and are arranged in increasing order from less sustainable to more sustainable. There are five levels of achievement, as displayed on the right in the table of point values: improved (encouraging), enhanced (on the right track), superior (remarkable performance), conserving (zero negative impacts), and restorative (restoration of resources and ecological systems, economic, and social sysContinued on page 10
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Continued from page 8 tems). The higher the level of achievement on a project, the more points that are achieved for a particular credit. Once the project is scored on the degree to which credits are met, the project is eligible to receive an award. The ENV SP on the project team may submit the scoring and supporting documentation to ISI. The ISI assigns an ENV SV (“Verifier”) to review and confirm the points achieved as submitted by the ENV SP. The Verifier will then make a recommendation for an award based on the percentage of possible points achieved: Platinum (50 percent and greater), Gold (40 percent), Silver (30 percent), and Bronze (20 percent). With such a variety of ways to be sustainable, it is nearly impossible to incorporate them all into one project to earn all of the possible points. Benefits of using the system include market recognition for high levels of achievement in sustainability; demonstration of social, economic, and environmental stewardship; ability to evaluate trade-offs and meet sustainability goals; and increased potential to receive grant funding. The rating system includes a credential program for individuals, through which they can become certified (ENV SPs and ENV SVs) to work on, submit, or verify projects for awards. The system’s “self-assessment checklist” is an Excel-based questionnaire used to guide the initial stages of planning for a project to be sus-
tainable. Questions are arranged by the five rating system categories, and the user completes the checklist by answering the questions as they relate to the project. The available responses are “yes,” “no,” or “not applicable.” The checklist is more or less a preliminary assessment to see where the project stands on its sustainable aspects, and it is used for internal purposes only (not submitted to ISI). The checklist is recommended to be completed prior to the project undergoing full evaluation and scoring. The guidance manual published by ISI assists ENV SPs with the scoring process and helps structure the information for verification. This manual includes detailed descriptions of all of the credits and the criteria that must be met within each level of achievement in order to receive points for that credit.
Perspectives The benefits of the rating system can be viewed from various perspectives as follows: Owner ! Projects are to set or meet sustainability goals ! Opportunity to be a “green city” ! Good public relations from Envision awards Engineering/Design Team ! ENV SPs provide services to increase sustainability on projects
Table 1. South County Advanced Wastewater Treatment Facility Existing and Expanded Plant Data
! Team looks beyond purely technical aspects of the project ! Uses guidelines to meet the owner’s sustainability goals Contractor ! Save money using this system and more efficient methods of construction execution ! Possibility to obtain more work through specialty certifications ! Recognition for awards Public ! Care about the environment that citizens breathe, see, live in, and use ! Would want to ensure the sustainable investment of tax dollars ! Community priorities are addressed in civil infrastructure projects Regulatory ! Sustainability aligns with the mission of regulatory agencies ! In many cases, using sustainable methods ensures permit compliance
Construction Phase Focus The rating system looks at the degree of sustainability during the whole project or phase. It supports the idea that project sustainability is cumulative and each phase contributes to the overall sustainability of the project. The construction phase is the link between the design phase and the operations and maintenance (O&M) phase. During the design phase, the team strategizes for sustainability and may write sustainability features into specifications or include sustainable aspects on the drawing sheets. Construction is where the design is implemented, and O&M is the actual use of the asset. It is recognized that operating the facility over the long term has the most impact on the sustainability of the project; however, the focus here is on the construction phase. In other words, the construction phase is short in relation to the useful lifetime of an asset (e.g., three years versus 20 years), but strategies can still be implemented during this phase.
Case Study Site Description As previously stated, Hillsborough County is currently expanding its AWTF from 4.5 to 10 mgd. This is the largest construction project the County has ever undertaken and the expansion doubles the footprint of the existing plant site. The facility is located in Ruskin (southeast of Tampa) and borders residential, agricultural, commercial, and transportation types of land
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use. South of the facility is a County potable water repump station, and an office building neighbors the plant site to the west. Another adjacent property west of the plant site is a cattle field, and further west of that is an Amazon.com distribution center. One benefit of the project location is that there are no residential zones immediately bordering the site. The site is unique because it is over a mile long, in a linear arrangement, and overlaps with the existing plant, making it subject to exacerbated shortterm hazards. Table 1 lists the components of the existing and expanded plant. With so many new structures and equipment, there are countless opportunities for sustainable construction to be practiced in the field at this point in the project’s life cycle.
Strategies for Sustainable Construction The concept of the dual nature of sustainability during construction involves two major components: the sustainable features of the design, and the sustainability during construction activities. It is important that sustainable features of the design are carried out during construction (e.g., conformance to drawings, specifications, etc.) and built as designed. Sustainability during construction activities includes proper sequencing for maintenance of plant operations (MOPOs), saving water and energy using efficient methods, and appropriate field decisions made by the contractor and other field staff. The examples that follow illustrate both types of sustainability during construction.
Leadership Leads to Sustainability Leadership is one of the five categories in the rating system. During plant shutdowns for pipeline tie-ins, sustainable strategies would include effective coordination and communication among involved parties, organized meetings, and written plans. For change orders, the sustainable strategy would be that the owner saves money with the reduction of change orders, therefore reducing the amount of work that is not competitively bid. For scheduling and phasing of work, the MOPOs need to be carefully coordinated for the portion of the existing plant within the construction zone. Testing and maintenance should be logged and well-documented. One example of this is how the general contractor performs regular maintenance on pumps and other stored equipment as stated in the specific warranty paperwork. For the Envision credit leadership category 3.3, a project will undoubtedly be more sustain-
able if the useful life of assets can be extended. Sustainable engineering designs can find a new use for existing unneeded plant components after demolition rather than disposing of them. For example, the AWTF expansion design calls for salvaging both existing oxidation ditches to serve as additional reject water storage in the future. Once the new bioreactor becomes operational, the existing oxidation tanks can be decommissioned, but not demolished. New equipment, such as the bioreactor mixers and motors, are logged in the County’s asset management system. The serial number, speed, horsepower, date put into service, photographs, etc., of each individual asset is entered into the asset management system, as well as any old asset that is being taken out of service. This method assists the County not only with knowing which assets it owns and where, but in the future to know which ones may be reaching the end of their useful life and may need to be replaced. Long-term planning for asset management is essential for forecasting budget, time, and workforce constraints and needs to be incorporated into the County’s capital improvement plan. Construction projects have many parties involved—owner, consulting engineering firms, general contractor, subcontractors, construction manager, project managers, plant manager, soils testing firms, resident observers, and field engineers—and the AWTF expansion is no different. A transparent dedication to teamwork and a genuine commitment to the project’s success will earn points for “collaboration” in the system’s leadership category. Interpretation of the drawings, specifications, requests for information, submittals, and change proposal requests require daily communication among field personnel and office managers. Care must be taken to use the proper channels of communication so that work is authorized by the appropriate person in charge. All parties involved want to feel that they are being kept informed on project status updates. Managers meet weekly at the AWTF general contractor’s trailer to discuss project progress, schedule, and potential challenges, including how to avoid and resolve them. From those meetings, leaders manage their staff in accordance with the agreed-upon items of the meeting. It is the managers’ responsibility to communicate information to their staff, and it is the responsibility of field personnel to inform their managers of any issues or questions from the field work. This includes clear and effective verbal and written communication. In short, an open line of communication among office and field staff is crucial to the success and sustainability of the project.
Materials Recycling and Control Contribute to Effective Resource Allocation As previously stated, resource allocation is one of the five rating system categories. Credits within this category encourage the efficient use and allocation of materials, energy, and water. Prior to the creation of Envision, this category summarized the typical idea of what sustainability meant: to use recycled materials, divert waste from landfills, buy local, and reduce energy and water use. However, as shown in the other strategies presented here, sustainable infrastructure covers much more than just these goals. For the typical construction practice of designating a concrete spoils pile (scraps, washout, leftovers from pours, demolished concrete, etc.), sustainable strategies would include transporting the concrete to a recycling facility, or using it as road base. Both strategies avoid it being taken to a landfill. The AWTF has a designated stockpile area at the north end of the site for excavated soils. The sustainable practice is to reuse this soil for backfill. The site contains several large bins to collect metal waste, which avoids it being sent to landfills and also allows the contractor to receive a rebate check ($/lb value) from the recycling facility. Another materials recycling sustainable strategy was the reuse of wooden forms for concrete pours instead of new pieces of wood each time. A rumble strip was placed at the main site entrance/exit that allows soils to be vibrated off the tires of vehicles and not leave the site. Restorative or innovative credits could be awarded for the energy subcategory if the following idea can be developed: since this is an expansion of an existing plant, devise a way to capture methane gas from the current treatment process and use it for energy during construction, such as for temporary power of construction equipment. Using renewable energy in this manner would allow the plant to be “energy neutral” by the reuse of methane gas for an inhouse power plant “generator.” Construction activities at a WRRF should be planned for daylight as much as possible for three main reasons: 1. Daylight is safer for the workers and observers because visibility is not limited due to lack of natural light. 2. Organisms are not disturbed by artificial light used during nighttime construction. 3. The energy requirement to power lights for nighttime work can be avoided. Continued on page 12
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Continued from page 11
Effective Water Management Earns Points A well-managed water use program during construction demonstrates a leader’s commitment to sustainability. When possible, it is best to use reclaimed water instead of potable water. Potable water quality is not necessary for operations such as hydroblasting concrete, dust control, and machine washdown, so using reclaimed water saves money. For the typical practice of refueling machinery (cranes, track hoes, forklifts, etc.), it is best to use double-wall fuel tanks and have kits nearby for quick cleanup of spills, so as to not contaminate groundwater. For the washout area for trucks, concrete scraps pile, and when cutting into pipelines, plastic liner systems should be in place to prevent groundwater contamination. When dealing with excessive rain, and during dewatering activities, silt fences and GeoHay bales can be used and eroded slopes can be restored. These strategies align with rating system credits RA3.1, RA3.2, RA3.3, and NW2.3. The AWTF expansion construction site is set up where pipes of reclaimed water from the
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existing plant provide service water for construction activities. This benefit is twofold: potable water use is avoided, and the percentage of plant reclaimed water use is increased (instead of that water being discharged directly into the receiving water body). A project may score high in the subcategory of resource allocation for water if a way can be devised for the reclaimed water to be reused multiple times within the construction process. For example, if a tank structure can be filled with reclaimed water for a 24-hour leak test and two days later a 30-in. pipeline needs to be pressure-tested, perhaps that same water can be used for both tests and gravity flow (preferred), or pumped from one to the other. A flow meter may be added to the hydrant from which the general contractor obtains reclaimed water in order to monitor how much is being used for these activities.
Resiliency to Hazards and Adaptation to Change Allow the Project to Overcome Challenges The rating system recognizes the importance of safety and emission reduction in sustainability (credits QL2.1, QL2.6, and CR1.2).
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Site observers, resident project representatives, workers, and other field staff should try to avoid fall/trip hazards, inspect ladders prior to use, communicate with machine operators, have a partner for confined space entry, and wear appropriate personal protective equipment. When applying coatings inside of a pump station or any other enclosed structure, it is important to use air exchange fans and face masks to protect the workers within from harmful fumes and particles. At the AWTF it was common practice for a worker to drive around the site in a water truck (filled with plant reclaimed water) and spray down the dirt roads for dust control on dry, windy days. This reduces the particulate matter, provides cleaner air for site personnel, and reduces air pollutants to neighboring areas. Since this is an expansion of an existing plant, the facility must still be able to operate normally during the construction phase. Furthermore, phasing out the existing systems, which are being replaced, takes careful planning and coordination since portions of the new plant are within the existing plant’s footprint. The existing plant should be resilient to the construction activities and be able to operate uninContinued on page 14
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Continued from page 12 terrupted. That was not the case at the AWTF; system shutdowns, unintentional water line breaks during excavation, and plant drain pump station overflows during high rain events have all occurred, which affected normal operation of the existing plant. Having a response plan for short-terms hazards increases the resiliency of the system and therefore makes it less vulnerable should a similar situation occur unexpectedly in the future. Envision credits CR2.2, “avoid traps and vulnerabilities,” and CR2.4, “prepare for short-term hazards,” illustrate that these ideas contribute to sustainability.
tor, and subcontractors to discuss practical measures that can be implemented to improve sustainability. ! Include sustainable methods in specifications. ! List the “lessons learned” at phase milestones; what could be done better next time to improve sustainability. ! Implement the strategies described throughout this document to increase the project’s score, therefore making the project a more sustainable infrastructure, as recognized by ISI.
Recommendations
Where the term “sustainability” used to be a vague concept, the Envision rating system provides a practical, numerical way to measure sustainability, and a project can be characterized by its score. Evaluating a project based on the specific credits makes it easier to assess, manage, track, improve infrastructure, and ensure utility sustainability. A higher score indicates the project is more sustainable, which could lead to better recognition and the potential for more long-term cost savings. A major advantage of the rating system is that the design team mem-
In order to put the rating system concept into practice, there are several recommendations that any construction project could undertake: ! Utilize the Envision checklist at the beginning of the project in order to consider sustainable aspects in the design phase, and later in the construction and O&M phases. ! Hold a preconstruction workshop with the owner, design team, site observers, contrac-
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Conclusion
May 2015 • Florida Water Resources Journal
bers think about the sustainable aspects of a project earlier on than they would have otherwise. Using the plant expansion of the AWTF as a case study, numerous strategies were presented that encourage sustainable practices during the construction phase of a water infrastructure project.
Acknowledgements I would like to thank the following for their assistance: David Bloome and Lisa Murrin with Hillsborough County; Michael P. Smith, José Rodriguez, and Kevin Leo with CDM Smith; and Tom Pedersen, CDM Smith (retired).
References • Yan Ji and Stellios Plainiotis (2006): Design for Sustainability. Beijing, China Architecture and Building Press. ISBN 7-112-08390-7. • Institute for Sustainable Infrastructure, The Envision™ Guidance Manual Version 2.0, (2012). • American Society of Civil Engineers (ASCE) Report Card for America’s Infrastructure (2009). !
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University of Florida Constructs Panama Canal Centennial Trail on Campus The University of Florida’s George A. Smathers Libraries, which houses the Panama Canal Museum collection, recently constructed the Panama Canal Centennial Trail, a 1/100th scale replica of the canal that traverses the campus and is seen daily by students on their way to class. The $15,000 exhibit commemorates the canal’s recent centennial anniversary, which was in 2014, as well as showcases the transformational expansion of the channel. A series of
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seven informational plaques corresponding to landmarks along the channel explain the history, engineering, and construction of the canal. The concept for the trail evolved when the Panama Canal museum moved to the University in 2012 and became the go-to destination for canal history and research. To display the length and significant landmarks of the Panama Canal, Frank C. Townsend, F. ASCE, of Jones Edmunds and a University professor, suggested bringing the wa-
May 2015 • Florida Water Resources Journal
tercourse to life in a small-scale model where visitors can see the path that ships make passing through the channel. Students and visitors begin the journey at the library, which represents the Atlantic entrance, and follow the blue dots through the locks found across a half-mile stretch of campus and end at the Pacific entrance, near the J. Wayne Reitz Union. Townsend conceived and provided design assistance for the trail. Born and raised in the Panama Canal Zone, Townsend is a third generation “Zonian.” Both of his grandfathers worked on the construction of the canal and were recipients of the Roosevelt Medal, which was issued by President Theodore Roosevelt to canal workers who completed two or more years of satisfactory service on the project. “The completion of the Canal was comparable, at the time, to the lunar landing,” said Townsend. “The trail on campus honors the legacy of the engineers’ masterwork. For me, personally, it is a way of sharing my experiences with the world.” Jones Edmunds helped to sponsor one of the exhibit’s zones. “The Panama Canal is a masterful accomplishment in engineering history, and these exhibits both honor the achievement and share it with new generations,” said Bob Edmunds, one of the founders of the Florida-based engineering firm. As of late March, the Panama Canal expansion project is 86 percent complete and is expected to be finished by 2016. !
T E C H N O L O G Y
S P O T L I G H T
Key Largo Wastewater Treatment District Utilizes Aqua-Aerobic Systems Technology Key Largo, the largest and northernmost of the Florida Keys, is a commercial fishing hub and scuba diving mecca. Good water quality and a healthy ecosystem are critical to its survival and a priority for the state of Florida. Originally installed in 2005, the Key Largo Wastewater Treatment District (WWTD) utilized a small alternative sequencing batch reactor (SBR) for treating the plant’s wastewater. After five years the plant was in need of an upgrade in order to address increasing flow rates for the population of 15,000 it now serves, and for future stringent effluent limits. To meet the strict nutrient limits it was facing and ensure the health of the local economy, Key Largo needed an advanced wastewater treatment solution capable of meeting Florida’s advanced water treatment (AWT) requirements, including nutrient removal, while providing process flexibility that results in energy savings. The district began exploring options, including a fivestage oxidation ditch and SBR technologies.
In addition, the planning staff visited nearby installations to see the potential technologies in operation. Following the selection research, Key Largo chose the Aqua-Aerobic Systems three-basin AquaSBR® sequencing batch reactor, followed by two AquaDisk® cloth media filters (12-disk units) for its upgrade in 2010. The new system was designed to process 2.88 mil gal per day (mgd) or 10,886 m3/day, average flow, and 5.75 mgd, or 21,735 m3/day, peak flow (Figure 1). The AquaSBR system operates on a simple concept of introducing a quantity of waste to a reactor, treating the waste in an adequate time period, and subsequently discharging a volume of effluent, plus waste sludge, that is equal to the original volume of waste introduced to the reactor. This “fill and draw” principle of operation involves the basic steps of fill, react, settle, decant, and sludge waste. The system may be designed to include seven individual phases of operation, but the inclusion or duration of any individual phase is based upon specific waste char-
Figure 1. Key Largo system annual data.
acteristics and effluent objectives. Where nutrient removal is required, a simple adjustment to the SBR’s operating strategies permits nitrification, denitrification, and biological phosphorus removal. The system is designed to meet the plant’s effluent objectives of 5 mg/l biochemical oxygen demand (BOD), 5 mg/l total suspended solids (TSS), 3 mg/l total nitrogen, and 1 mg/l total phosphorus. Based on experience with the plant over the past few years, Key Largo’s lead operator, Jered Primicierio, states, “What I’ve noticed with the Aqua-Aerobic plant is that carbon usage is minimal in achieving nitrogen removal. We use the actual strength of the wastewater or carbonaceous BOD within the influent to denitrify. The standard for removing phosphorus biologically is around 3 mg/l, and we treat up to 4 mg/l. We actually take out 4 mg/l of phosphorus biologically, so we’re well above the standard.” Key Largo is able to further reduce its TSS and remove additional phosphorus with the AquaDisk cloth media filtration system featuring OptiFiber® media. With the outside-in configuration of the AquaDisk filters, influent enters the filter unit and contacts the outside of the filter disk. Filtrate passes through the pile cloth media by gravity and is removed from the hollow area inside the filter disk through a hollow shaft that supports the individual disks. As solids accumulate on the surface of the media, the water level surrounding the disks rises. Once it reaches a predetermined level, automatic backwashing begins. The disks rotate as backwash shoes contact the media surface and a vacuum is applied to remove the captured solids. During backwash, fibers fluidize to provide an efficient release of stored solids. Filtration is not interrupted and heavier solids settle to the bottom of the tank and are pumped to a digester or other collection area of the treatment plant. According to Primicierio, “After the treated water goes through the cloth media disk filters, we’re actually achieving a .6 mg/l in total phosphorus, and that’s probably a two-year average.” Continued on page 18
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Key Largo Wastewater Treatment District Expansion.
Two AquaDisk filters with covers.
Continued from page 17 To enhance the plant’s process control capabilities, Key Largo also incorporated an IntelliPro® process monitoring and control system. The IntelliPro system is designed to offer an essential link among operations, equipment, and treatment objectives. It actively influences the treatment process by proactively responding to changes as they happen and efficiently manages overall system performance. Through the use of process instrumentation, the system can actively control process parameters within the biological system, such as dissolved oxygen (DO) and system mass, and even modify the cycle structure. The addition of the nutrient module and instrumentation adds the capability of automatically monitoring and controlling biological and chemical nutrient removal. Key Largo noticed a drastic improvement in the monitoring and control of the biological process, which is attributed in part to the IntelliPro® process monitoring system. The most beneficial aspect for Key Largo is the ability to fully monitor the process, such as realtime oxidation-reduction potential (ORP), pH, TSS, and DO concentrations in each SBR basin. The plant also makes use of a majority of the system’s additional features, including active mass control and trending capabilities. Says Primicierio, “The other beautiful thing about the DO control is that we’ve actually seen a cost savings of up to $10,000 a month in the last year after we’ve dialed the air in, with regard to time and the DO set point.” The health of the environment certainly has an economic impact on the Florida Keys. Tourism is based on snorkeling, scuba diving, and fishing, and many local livelihoods depend on the commercial fishing industry of the Keys. It is extremely important to keep the environment clean and functioning. As Key Largo continues to grow, the advanced nutrient removal technologies and streamlined plant optimization technologies from Aqua-Aerobic Systems will ensure that the wastewater facility will grow with it, while protecting the livelihood and habitat of the region through exceptional water quality. To learn more about these and other advanced water and wastewater treatment technologies from Aqua-Aerobic Systems Inc. please visit www.aqua-aerobic.com or contact the company’s local representative in Florida, Envirosales Inc., at (863) 314-0616. !
Technology Spotlight is a paid feature sponsored by the advertisement on the facing page. The Journal and its publisher do not endorse any product that appears in this column. If you would like to have your technology featured, contact Mike Delaney at 352-241-6006 or at mike@fwrj.com.
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SPOTLIGHT ON SAFETY
FWEA Safety Committee Begins New Leadership
Doug Prentiss Sr.
S
ome of you may be aware that the FWEA Safety Committee is now under new leadership and is actively seeking new members and participants. The committee is now chaired by Judd Mooso of Destin Water Users, and Scott Holowasko, with Gainesville Regional Utilities, serves as the vice chair. The committee will meet once each year during the Florida Water Resources Conference (FWRC) and, at the conference in 2016, it plans to begin offering safety training classes with continuing education units. The instructors will be members of the committee and attendance will be included with registration to the conference. This year, FWRC will be held May 3-6 at the Caribe Royale Resort in Orlando. The committee will meet on Monday, May 4, at 1 p.m., in Bonnaire Room 5 and 6.
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Our goal is to gather utility professionals from around the state in an effort to begin building a network of folks who have responsibility for the safe operation of their water and wastewater facilities. The role of safety in our profession can be a daunting task, so it is our ambition to invigorate the committee and pool our resources to enable us to reach out and help each other along the way. This will be a great opportunity to get involved by becoming a volunteer so we can begin to discuss topics of interest and plan for the way forward. This article is our initial effort to determine the level of interest. It is not our intent to burden anyone with extra work, but rather to establish an atmosphere that allows us to discuss any safety issues our companies may face. Ultimately, we’d like to be able to provide each other
May 2015 • Florida Water Resources Journal
with ideas, templates, and business practices that have proven successful in our experience. The FWEA Safety Committee goals are: ! Increase membership and participation in the committee. ! Provide safety-related information useful to FWEA members. ! Align safety committee activities with FWEA goals and objectives. Please stop by the meeting if you are interested; we’d love to meet you. If you have any questions, contact Judd Mooso, the FWEA Safety Committee chair, at jmooso@dwuinc.com or at 850-337-3915. Doug Prentiss Sr. provides a wide range of safety services throughout Florida. !
F W R J
Priorities: Getting the Most From Your Capital Improvement Plan Jason DeStigter
A
ging water and wastewater infrastructure, managing capital costs, and the ability to fund capital programs, are issues that are continuously ranked by water and wastewater utility leaders as the top five industry issues in Black & Veatch’s annual report, “Strategic Directions: U.S. Water Industry.” The urgency of the highlighted issues demonstrates the growing need for comprehensive asset management programs and solutions around the prioritization and optimization of capital expenditures. Good practice asset management focuses on balancing performance, cost, and risk. Additionally, a critical component in any asset management program is the development and proper implementation of a robust capital prioritization and optimization process. Over the course of the past decade, Black & Veatch has developed an innovative budget prioritization and application process that uses advanced analytics to quantify and optimize planning outcomes that explicitly take into account uncertainty and risk. This article provides an overview of the process and highlights the following: ! How the process supports improved utility decision making
! How improved decision making enhances value from infrastructure investments and new plant and system improvements ! Examples from a recent utility capital planning engagement Building an improved understanding of risk and how that risk can impact a utility both financially and in other ways (such as environmental impacts, safety, etc.) is a key outcome of the process.
Capital Prioritization and Planning The goal of the budget prioritization and optimization process is to minimize long-term system costs, while maintaining high levels of service and mitigating unacceptable system risks. Figure 1 is a high-level flowchart of the capital prioritization and optimization process used to achieve this goal. Each of the steps in the flowchart is described in the subsections that follow the figure. Project Identification and Justification Project identification is a key step to ensure that projects are identified in a manner
The capital prioritization and optimization process described helps utilities achieve balance among performance, cost, and risk through objective investment planning.
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Figure 1.
Jason DeStigter, P.E., is a manager within Black & Veatch’s asset management practice in Overland Park, Kansas.
consistent to capture both the full costs and benefits associated with each improvement or change to an asset or system. Identified projects typically have several investment drivers, such as growth, regulatory, safety, efficiency or cost savings, repair and rehabilitation, and customer service. The prioritization and optimization process has the flexibility to include all of these different types of projects. Projects are gathered from the current capital improvement plan (CIP), master plans, asset management systems, and condition assessment evaluations. Once the candidate projects are determined, a data-collection step validates the inputs that will later be used in the prioritization process. This helps assure that assumptions are valid, realistic, and reasonable. The required skill sets that are necessary for this project identification and assumptions evaluation include engineering, regulatory, commercial/financial, and utility asset management.
Project Assumptions Once each project is identified, an associated assumptions form is completed as part of the capital prioritization process. A template was developed to consistently and transparently develop the assumptions necessary for each project and it’s tailored to each utility performing this process. Additionally, this form serves as an important quality control tool as it ensures assumptions are reviewed prior to their use in the financial templates. The form contains a section for qualitative and quantitative assumptions for each project. Qualitative assumptions are based on the main drivers for each utility to complete a project, including planning criteria assumptions (e.g., regulatory, safety, service level, environmental, criticality, etc.). Each planning criterion is then scored using predefined scoring scales and definitions. Quantitative assumptions include capital costs, operations and maintenance (O&M) costs (before and after the project is completed), growth rates, potential revenues (if any), failure costs (including lost revenue), and failure probability curves. Assumptions are commonly developed using the results of condition assessments and by obtaining feedback from utility staff during a series of assumptions form workshops. Financial Efficiency Simulation and Ranking The process links each project assumptions form to a financial template that is used for Monte Carlo simulations, which calculate the range of net present value (NPV) cost for each project through its life cycle. The probabilistic results generated by the financial templates form the basis for prioritizing the financial efficiency and cost-effectiveness of projects. Rather than single-point estimates, the results are probability distributions of projected NPV costs, such as the one depicted in Figure 2. In Figure 2, the x-axis of the probability distribution shows the range in NPV capital costs for the project given a designated planned installation year. The y-axis of the distribution shows the relative probability of a certain cost occurring. Input distributions for the following assumptions are included in the financial template for each candidate project (note: not all projects will include values for all of these assumptions): ! Capital cost ! O&M before project install ! O&M after project install ! Revenue (linear, nonlinear, rate, and volume basis) ! Failure consequence
Figure 2. Example Probability Distribution
Table 1. Criteria Weighting Factors
A benefit of this process is the ability to evaluate ranges of potential costs and even avoided costs (e.g., failure costs). By modeling the full range of consequences, project risk exposure can be evaluated and quantified for decision making purposes. In order to take into account the magnitude and probability of cost risk, several financial efficiency parameters are calculated. These financial efficiency parameters help organize the probabilistic results into results that can be easily compared across projects for comparison and prioritization. The first parameter is the expected financial efficiency of the project that measures a ratio of the NPV benefit of the project compared to the project cost. Risk exposure is measured by calculating a risk-mitigated ratio for the project that looks at the extremes of the
probability distribution of NPV results. This metric measures the amount of risk or uncertainty mitigated by implementing the project. The prioritization process is also used to identify projects where the financial benefits do not necessarily outweigh the costs of doing the projects. Projects such as these may have additional factors other than cost that risk influencing their selection, such as safety considerations or regulatory constraints. These factors are taken into account during the prioritization process through the balanced score results discussed later, as well as by constraining the optimization model. For each project, the optimization model includes constraints on the earliest available install year and the latest required install year to allow for qualitative drivers to schedule projects. The next section discusses in further deContinued on page 24
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Continued from page 23 tail the optimization model.
Prioritization and Timing of Projects
One of the valuable aspects of the financial efficiency approach is that the financial templates and assumptions forms are able to evaluate a wide variety of project installation years in a relatively short amount of time
Table 2. Example Financial Prioritization Results
through simulations. At this step in the optimization process, projects are timed so that utility risk tolerance levels are not exceeded. The optimization model uses the combination of the budget scenario and nonfinancial planning criteria constraints with the NPV results to maximize the NPV benefit for the utility given these constraints. In other words, it checks every combination of project installation dates that will: ! Maximize NPV benefit ! Stay within the annual budget and schedule constraint levels for each scenario The NPV benefits and budget/schedule constraints are achieved using a genetic algorithm software tool. Similar to the @Risk™ Monte Carlo simulation software, the optimization process uses an off-the-shelf Microsoft Excel™ add-on software module (Evolver™) to perform the genetic algorithm. The module software is a companion tool to the simulation software as part of the Palisade’s Decision Tools Suite, which is an integrated set of programs for risk analysis and decision making. Project timing optimization is then conducted for all projects to arrive at a portfolio
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optimization result. Particular focus is given to investments that have a significant budget impact or are being considered for delay beyond their planned installation date due to utility budget constraints. The projects are first scheduled based on the risk tolerance levels of the utility. Once all projects are within the defined risk tolerance, projects are scheduled based on the maximum financial benefit to the utility. The result is a target schedule without regard to budget constraints. Next, budget constraints are incorporated into the scheduling process and any changes to install years due to budget constraints are then recalculated. In addition to prioritizing projects using financial efficiency, the planning criteria are used to balance all relevant nonfinancial issues. Each project is scored against each planning criterion using a scale of 1 to 10, with standard definitions and scoring scale for each criterion. The score is then multiplied with the applicable weighting percent for that criterion to create a balanced scorecard result for the project. Table 1 provides an example of the criteria weighting factors that a utility can use when developing the balanced scorecard. The final step of the prioritization process is to incorporate planning criteria scores, project rankings, and budget constraints into the implementation schedule.
Table 3. Example Project Rankings
Process Results As described previously, the prioritization process involves combining project prioritization based on financial risk with project prioritization using a balanced scorecard approach (financial efficiency and planning criteria). Table 2 shows the expected outcome NPV results for a subset of projects for a recent client. The combination of the quantitative and qualitative results provides a balanced scorecard evaluation for each project. Each project is evaluated using a weighted criteria matrix scoring process. In the example in Table 3, four planning criteria are used in the scoring process: ! Financial efficiency ! Regulatory and environmental ! Safety ! Customer service Each criterion is defined at the beginning of the prioritization process before the assumption forms are completed. Financial efficiency is evaluated using the financial evaluation template, and the other three criteria are scored when the assumptions form is complete. Prioritization results are used to derive the capital plan schedule in order to Continued on page 26
Figure 3. Example Prioritization Results
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Continued from page 25 schedule projects to minimize financial risk, while at the same time taking into account the nonfinancial project drivers. Table 3 is an example of the project ranking table results and Figure 3 visually compares project scores for a number of example projects. The prioritization model is used to calculate the risk-weighted 40-year net NPV of future cash flows for several scenarios of the full portfolio of capital projects, including: ! Run-to-failure scenario – assumes projects are delayed until assets fail or installation is required for another reason (e.g. regulatory constraint) ! Current CIP scenario - if the existing CIP is implemented as planned ! Optimized CIP scenario – if the recommended capital schedule using the optimization results is followed
Figure 4. 40-Year Net Present Value Cost Comparison for the System
Figure 5. Portfolio Risk Reduction Compared to Cumulative Capital Spend Most of the forecasted risk reduction achieved by the investments occurs in the first part of the study period, while more steady risk reduction occurs during the second half of the period. This validates that near-term capital dollars are being utilized on the projects and assets that expose the utility to the most risk, while projects with less or no risk are scheduled later in the study period.
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Figure 4 calculates the risk-weighted financial results for all three capital schedules listed. The Current CIP has an expected outcome of $76 million in risk-weighted NPV savings ($247 million minus $171 million results in $76 million in NPV cost savings), while the optimized CIP scenario results in an expected outcome of $89 million in risk-weighted NPV savings ($247 million minus $158 million). The current CIP shows a 31 percent reduction in NPV cost compared to the run-tofailure scenario, while the optimized CIP has a 36 percent reduction. The 5 percent additional reduction, or $13 million, represents a 36 percent decrease in overall system risk through optimization of the current CIP, demonstrating the value of performing capital optimization even with the same budget constraints. The results noted in Figure 4 show the risk reduction from a risk-weighted financial perspective. The next set of example results incorporate the nonfinancial criteria, in addition to the financial efficiency results. The planning criteria score other risks to the utility that are difficult to quantify from a financial perspective. For many utilities, these include well-established triple-bottom-line scoring criteria. Figure 5 shows the financial and nonfinancial risk reduction for an example portfolio of projects and compares it to cumulative capital expenditures by year. As part of the capital planning process, it is valuable to understand the risk of delaying a project so that this risk can be considered in making budget decisions. Figure 6 is an example of what is developed to understand and quantify this risk for each project. Implementation Schedule One of the final results of the prioritiza-
tion process is an optimized implementation schedule and project rankings that meet utility risk tolerance levels, achieve maximum cost effectiveness, and incorporate budget constraints. The planning criteria scoring matrix is used to calibrate the scheduling of projects to ensure that nonfinancial criticality scores are incorporated in the planning process appropriately. For some clients, the balanced scorecard prioritization results are used as the primary prioritization and optimization metric to drive the capital plan schedule. Figure 7 shows an example implementation schedule for the optimized CIP. For this example, since the budget constraint is based on an existing CIP, the optimization model allows for unused funds to be carried over from year to year. A corresponding set of prioritization results (similar to the example NPV and balanced scorecard tables and figures) match the optimized schedule shown in figure 7.
Conclusion Good practice asset management programs strive to optimally balance performance, Continued on page 28
Figure 6. Project Delay Impact The figure shows the NPV cost of a two-year delay (moving from the optimized blue curve to the grey ‘two-year delay’ curve). As the project is further delayed, the NPV of cost will approach the run-tofailure cost range (red-dashed curve).
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Figure 7. Capital Schedule: Optimized CIP Under Budget Constraint The stacked bar charts in the figure break down the total capital cost by the various asset classes shown in the legend. The red curve shows the budget constraint used in the optimization process.
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Continued from page 27 cost, and risk across the enterprise. Through good practice asset management, decision making is made more objective and investments are better aligned with the utility strategic plan. Capital prioritization enables objective decision making because it is driven by explicit financial risk results and a balanced scorecard that incorporates nonfinancial project and system drivers. The incorporation of budget constraints and integration with a utility financial/rate model enable the prioritization and optimization process and help drive integrated planning across the utility. The results provide an important bridge between a utility financial plan (typically focused on balancing cost) and the balancing of system risk and performance, along with customer cost impacts. Ultimately, the entire process helps utility management take a long-term and objective view towards achieving value for customers through the balancing of performance, cost, and risk. The water utility client referenced in this article, for example, identified more than $10 million in savings through capital prioritization, without affecting risk levels. !
FWPCOA TRAINING CALENDAR May
SCHEDULE YOUR CLASS TODAY!
4-7 ....Backflow Tester ........................................Deltona ............$375/405 18-21 ....Backflow Tester ........................................St. Petersburg ....$375/405 18-22 ....Stormwater Level C, B ..............................Deltona ............$260/280 29 ....Backflow Tester Recert*** ........................Deltona ............$85/115
June 8-12 ....Wastewater Collection C, B ....................Deltona ............$325/355 15-18 ....Backflow Tester ........................................St. Petersburg ....$375/405 22-26 ....Wastewater Collection A..........................Deltona ............$275/305 22-26 ....Water Distribution 1 ................................Deltona ............$275/305 22-26 ....Stormwater A ............................................Deltona ............$275/305 26 ....Backflow Tester Recert*** ........................Deltona ............$85/115
July 6-10 ....Reclaimed Water Field Site Inspector ....Deltona ............$350/380 13-15 ....Backflow Repair ........................................St. Petersburg ....$275/305 24 ....Backflow Tester Recert*** ........................Deltona ............$85/115 27-30 ....Backflow Tester ........................................Deltona ............$375/405 Course registration forms are available at http://www.fwpcoa.org/forms.asp. For additional information on these courses or other training programs offered by the FWPCOA, please contact the FW&PCOA Training Office at (321) 383-9690 or training@fwpcoa.org. * Backflow recertification is also available the last day of Backflow Tester or Backflow Repair Classes with the exception of Deltona ** Evening classes *** any retest given also
You are required to have your own calculator at state short schools and most other courses. Florida Water Resources Journal • May 2015
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Certification Boulevard Test Your Knowledge of Operations and Utility Management Topics 5. What safety precaution should be taken when starting a positive displacement pump? A. B. C. D.
Roy Pelletier 1. What is the best parameter to use indicating that trouble is starting in an anaerobic digester? A. B. C. D.
2.
Increase in carbon dioxide Decrease in pH Increase in sludge volume Increase in volatile acid/alkalinity relationship
If polymer consumed in a belt filter press (BFP) is identified to be about $25 per dry ton, is this an acceptable cost of polymer usage for a BFP? A. No, it is way too high. B. Yes, this is acceptable. C. There is not enough data to calculate this parameter.
6. What is the system called that requires proper documentation associated with the person who collects samples, the person who receives the samples in the lab, and the lab technician who performs the tests? A. B. C. D.
4. Which term is most related to vector attraction reduction in an aerobic digester?
Sample performance Chain of custody Mapping Sample journal
7. What is a typical percent volatile content of activated sludge mixed liquor suspended solids for municipal activated sludge processes? A. B. C. D.
3. Which of the following is a harmful physical agent to microbiology? A. Hydrochloric acid B. Methane C. Solvents D. Temperature
The discharge valve should be closed. The inlet valve must be grounded. The discharge valve must be opened. There should be no people near the pump.
5 to 15 percent 30 to 40 percent 50 to 60 percent 70 to 80 percent
8. Of the items in the list of answers, what may be the FIRST corrective action taken to resolve suspended flocculation conditions in a secondary clarifier if the microscopic exam reveals an abundance of filamentous organisms?
A. Settleometer B. Pathogen C. Specific oxygen utilization rate (SOUR) D. Food-to-mass ratio (F/M)
A. Decrease the dissolved oxygen (DO) B. Increase the DO C. Increase the waste activated sludge (WAS) rate D. Reduce the return activated sludge (RAS) rate
LOOKING FOR ANSWERS?
Check the Archives Are you new to the water and wastewater field? Want to boost your knowledge about topics youʼll face each day as a water/wastewater professional? All past editions of Certification Boulevard through 2000 are available on the Florida Water Environment Associationʼs website at www.fwea.org. Click the “Site Map” button on the home page, then scroll down to the Certification Boulevard Archives, located below the Operations Research Committee.
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9. What 15-minute test will help to identify the concentration of aeration mixed liquor suspended solids (MLSS) or thickened sludge from a gravity belt thickener system? A. Laboratory total suspended solids (TSS) B. Settleometer C. Centrifuge spindown D. Sludge judge 10. A spray field has a total of 25 acres and is divided into four equal zones. Only one zone may be operated at a time and the permit states that no more than 4 in. of water can be applied to the zone. How long can a zone be operated at a rate of 0.5 mil gal per day (mgd) before it must be rotated to another zone? A. 48 hours C. 4.2 days
B. 1.4 days D. 144 hours
Answers on page 62
SEND US YOUR QUESTIONS Readers are welcome to submit questions or exercises on water or wastewater treatment plant operations for publication in Certification Boulevard. Send your question (with the answer) or your exercise (with the solution) by email to: roy.pelletier@cityoforlando.net, or by mail to: Roy Pelletier Wastewater Project Consultant City of Orlando Public Works Department Environmental Services Wastewater Division 5100 L.B. McLeod Road Orlando, FL 32811 407-716-2971
FWRJ COMMITTEE PROFILE This column highlights a committee, division, council, or other volunteer group of FSAWWA, FWEA, and FWPCOA.
University of Florida Team.
Kristiana Dragash, winner of the 2014 YP of the Year award.
University of Miami team.
Students and Young Professionals (S&YP) Committee Affiliation: FWEA Current chair: Danielle Bertini, Carollo Engineers Scope of work: To develop and implement programs to increase the activity and membership of students and young professionals within the association. We support and invest in our students and young professionals by hosting the Student Design Competition (SDC) and Poster Competition, awarding the Norm Casey Scholarship, selecting the YP of the Year, and coordinating various YP events throughout the state. Recent accomplishments: This past year, our committee has focused on: • Establishing a stronger connection with colleges throughout the state. • Providing more guidance to faculty advisors and students earlier in the competition process. • Connecting students with industry professionals and/or local utilities. We have accomplished these by streamlining the information given to the students and by reaching out to local utilities and industry professionals to provide problem statements or act as a mentor. Committee members have also visited most universities to promote the SDC . Last year, the University of South Florida (USF) and the University of Miami (UMiami), won first place in their categories at the SDC. We sent both teams to the Water Environment
Federation Technical Exhibition and Conference (WEFTEC) to participate in the national competition. The USF took first place in the wastewater category and UMiami took fourth place in the environmental category. Florida teams continue to do well in representing the state at the national level! This is also the first year we are hosting the S&YP Poster Competition at the Florida Water Resources Conference (FWRC). Students and young professionals will be presenting their projects and research outside the exhibit hall. Poster themes will include wastewater engineering, water resources, and other environmental/sustainability topics. Current projects: Lindsay Marten, with Stantec in Sarasota, was recently selected as the 2015 YP of the Year. Lindsay was recognized for her dynamic leadership and involvement with FWEA this past year and her potential as a future FWEA leader. She will be representing Florida at the national AWWA/WEF YP Summit in 2016. The S&YP Committee will also be hosting several events on Monday, May 4, 2015, at
FWRC: • Student Design Competition • Career Panel/Resume Workshop (part of the SDC) • First Annual S&YP Poster Competition • Joint AWWA/FWEA YP Social Future work: Our goals for 2015/2016 include: • Continuing to provide guidance and assistance to local universities. • Expanding our student outreach efforts to grade school students. • Promoting both engineering and nonengineering career tracks. • Hosting a student paper competition at the 2016 FWRC. • Fundraising so we can continue to offer benefits to our participants/award winners Committee members: • Tim Ware, vice chair, American Water • Kristiana Dragash, director at large, Carollo Engineers • Rebecca Oliva, past chair, CDM Smith • Isaac Holowell, CDM Smith • Samantha Hanzel, Greeley & Hansen • David Hernandez, Hazen & Sawyer • Kristen Andre, Arcadis • Lauren Davis, Arcadis • Matt Munz, MWH • George Dick, University of South Florida • Yanni Polematidis, CDM Smith • Samantha Nehme, Stantec ! Tim Ware and Danielle Bertini, committee vice chair and chair.
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FWRJ READER PROFILE cadets on all classes that pertain to water distribution. I am also an instructor for FWPCOA onthe-road classes for water distribution, level two and level three, and classes for backflow assembly tester certification and backflow repair and maintenance certification. I attended the first backflow assembly tester certification class taught in Florida at the University of Florida Training, Research, and Education for Environmental Occupations (TREEO) Center in 1979.
Raymond Bordner Retired
Work title and years of service. I worked for City of St. Petersburg as the water distri-bution supervisor and retired after 37 years of service. For the past nine years I have worked part time for Pinellas Technical College as an instructor for the Public Works Academy. I teach classes for the academy’s cadet program and for the water distribution apprenticeship program. What does your job entail? As a water distribution supervisor my responsibilities included the field services division (meters, backflow prevention, and reclaimed water), valve and hydrant maintenance, new small services, and horizontal directional drilling sections. At the Public Works Academy I instruct academy
What do you like best about your job? Water distribution has been my livelihood and passion for the past 46 years. As an instructor I really do enjoy passing on what I have learned over the years to those who are currently oversee the maintenance and operation of water distribution systems, as well as those who protect distribution systems from cross-connection through backflow prevention programs. What organizations do you belong to? I have been a member of FWPCOA since 1982 serving the association and its members as committee chair of the Systems Operators Committee for over 10 years. I also serve on the Education Committee and Backflow Committee. I am an honorary life member of the association and had the honor of serving as its president in 2011 and 2012. I hold an active Florida Department of
Environmental Protection (FDEP) Class 1 Distribution System Operator License No. 0016478. I have served on the FDEP Technical Advisory Committees and am currently serving on the Exam Review Committee, Office of Certification Programs for Water Distribution. How has the organizations helped your career? The FWPCOA has played a key role throughout my career as a water distribution operator. Networking with other dedicated and professional operators from around the state has provided me with a wealth of information in the professional operation and maintenance of water systems, information and support that can only be gained through personal contact with other dedicated and knowledgeable operators. What do you like best about the industry? I was born and raised in Florida and have seen many changes in the state’s water environment. Having the knowledge and understanding that there are so many dedicated and professional members of FWPCOA, FSAWWA, and FWEA who work around the clock to protect Florida’s water and ensure that there will be plenty of clean safe water for future generations who visit or who call Florida their home is heartening. I’m proud that I have had the opportunity to play a small part in protecting our drinking water supplies as that water flows through a water distribution system so no one who visits or resides here will have to ask, “Is the water I am about to use safe?” What do you do when you’re not working? My life outside my profession is my family. I cannot spend enough time with my grandchildren, John Ray and Katie. They have a special way of making me think that I am younger than I am and I enjoy every minute of time I have with them. I also enjoy ridding my Honda Shadow on back roads, relaxing and refreshing my spirit with the wind blowing in my face while enjoying our beautiful state. !
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University of Central Florida Receives Gift for Engineering Department Student researchers at the University of Central Florida (UCF) College of Engineering were very lucky this St. Patrick’s Day when they were visited by the Jones Edmunds cofounder and director, Bob Edmunds. Edmunds arrived at UCF on March 17 with a wealth of infor-
mation to share as a guest lecturer during Dr. Steve Duranceau’s environmental systems engineering design class. In addition to his engineering expertise, Edmunds also presented a check from his firm for $15,000 to the University of Central Florida Research Foundation in support of environmen-
tal engineering research. Jones Edmunds’ partnership with the engineering department dates back more than a decade. In the past 10 years, it has contributed nearly $100,000 toward UCF’s research in water quality, treatment, storage, and distribution of portable water systems.
Dr. Steve Duranceau (middle left) receives check from Bob Edmunds (middle right).
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“It has sincerely been a pleasure to work with the University of Central Florida for all these years and see our relationship continue to grow,” said Edmunds. “Our firm is constantly impressed by the work of these students and proud to contribute to their education. We look forward to seeing the impact they have in the field of environmental engineering.” The firm and the university’s engineering team recently worked together on the design of the Polk County Imperial Lakes Water Treatment Plant. Soon after it was placed into operation, Duranceau and several of his students toured the facility. The university helped with the pilot testing for the plant’s treatment technology, which was a good way to “close the loop” with the students and let them see the finished product.
FSAWWA SPEAKING OUT
Florida Section AWWA Hosts Regional Meeting of Section Officers Mark Lehigh Chair, FSAWWA
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very ten years the Florida Section of AWWA gets the opportunity to host the Association’s Regional Meeting of Section Officers (RMSO). It was our turn again this year, and on March 25-27, we took the opportunity to show off Florida and the section. The AWWA structure has its 43 sections grouped into five regions in North America. Florida is a part of Region II, along with the following sections in the southeast region: North Carolina, South Carolina, Puerto Rico, West Virginia, Alabama-Mississippi, Georgia, Virginia, and Kentucky-Tennessee. What is RMSO you ask? It’s a great opportunity! And it’s a yearly opportunity for section leadership to meet with AWWA staff and other section leaders from our region. These meetings are one of the most important tools for gaining updated information on AWWA and sharing
ideas with other sections. This year was certainly no different. Planning for this event started at the 2014 Florida Water Resources Conference and ramped up at our Fall Conference at the end of last year. With so many locations throughout the state to choose from for the meeting site, it was a difficult decision to settle on one. Grace Johns, the current FSAWWA vice chair, had such vision and passion to have the event in Key Largo that we choose it by a unanimous decision. Grace took the lead and treated everyone to a beautiful location and perfectly planned event. Thank you, Grace! Our guest section leaders and AWWA staff were given a front-row seat to some of the best natural scenery and entertainment Florida has to offer. On Wednesday, March 25, as everyone arrived, the Florida Section hosted a meet and greet reception. We were trolleyed over from the hotel to a glass-bottom boat to take us to our destination. As we floated on top of the crystal clear water and glided across the Molasses Reef, we were treated to a beautiful display of coral, fish, turtles, and even a shark. There were a lot of oohs and aahs from all. It was a great opportu-
Viewing sea life through the glass bottom boat.
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nity to relax and get to know other section leaders in a casual, laid-back atmosphere. The meetings kicked off first thing Thursday morning with an informative presentation by AWWA Treasurer David Rager on “AWWA 2020 : A Path to One AWWA.” His talk was based on the AWWA strategic plan and its five main pillars: ! First, that sections are AWWA’s primary business partner. ! Second, that AWWA is a provider of total water solutions. ! Third, that while AWWA is a North American association, its impact is felt globally. ! Fourth, that utilities are core members. ! And lastly, that this would be a plan for all of AWWA. Most of the rest of the day was dedicated to section members sharing ideas about membership and education. This is one of my favorite components of RMSO. These sharing opportunities have transitioned from annual reports of general section activities to topical, focused discussions. The quality of information shared has led to greater adoption of new ideas, programs,
Attendees share their ideas at one of the meetings.
Tom Curtis had the honor of sounding the ship’s horn at sunset.
FSAWWA staff and officers, and meeting attendees, at the hosted dinner.
and initiatives among the sister sections. These are the ideas and programs that work—the things that the other sections are doing that are successful and bring value back to the membership. This is the true value of RMSO and why it’s such a successful event. You leave re-energized, with a handful of ideas and opportunities to serve your members. You build relationships with the other sections in your region that continue throughout the year. The ideas are not just shared; sections make them a reality by supporting and assisting each other to become “One AWWA.” The evening was capped off with a reception and dinner at Snooks Bayside Restaurant. The weather was perfect, the sunset was gorgeous, the food was tasty, and the fellowship was enjoyed by all 96 attendees. It was simply a perfect location and a great event hosted by the section. Thanks again to Grace Johns for taking the time to plan and coordinate this event and to Hazen and Sawyer for supporting her. Early Friday morning the sections assembled again for an informative presentation on branding and a legislative update from AWWA Deputy Executive Director Tom Curtis. Tom provided a recap of the recent DC Fly-In, which is held every year to inform new legislators in Washington about drinking water issues. He pointed out some the key issues on Capitol Hill, chanting his mantra “Free WIFIA.” The event was capped off with a silent auction to raise money for Water For People. Barika
Items available for bid at the Water For People auction.
Poole coordinated this effort and brought in many eclectic, Florida-made and Floridathemed items, from art work and jewelry to an autographed picture of Dale Earnhardt Sr. to craft beer and wine. We also offered items from some of the countries where Water For People has its projects. The Puerto Rico Section brought a bottle of Rum that kicked off a bidding war and was won by a Florida Section representative. This was a fun and successful event that raised over $1500.
On a side note, we missed seeing Christopher McGinness, our section services manager from AWWA. He was pulled away by a lastminute, but very welcome new addition to his family! Congratulations Christopher, from the Florida Section and all the members of Region II. I’m looking forward to the meeting next year and the opportunity to renew old friendships, build new ones, and steal some more great ideas! !
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Turning a Pollutant Into a Resource: An Overview of Nutrient Removal and Recovery at Water Resource Recovery Facilities Barry Liner and Sam Jeyanayagam In excess, nutrients can be harmful water pollutants. Nutrients are found in agricultural and home fertilizers, as well as agricultural operations. Sources include confined animal feeding operations, industrial pretreatment facilities, septic systems, and water resource recovery facilities (WRRFs), as well as municipal and industrial stormwater runoff. According to the U.S. Environmental Protection Agency (EPA), more than 100,000 mi2 of rivers and streams, close to 2.5 million acres of lakes and ponds, and more than 800 mi2 of bays and estuaries are affected by nitrogen and phosphorus pollution. Excess nutrients can lead to algal blooms, which can produce toxins and result in hypoxic zones. Algal blooms cost the tourism industry some $1 billion annually. These substantial impacts are the reason regulatory nutrient limits are expanding across the country. Nutrient Removal at WRRFs Nutrient management begins with nutrient removal to meet permit requirements. The WRRFs can achieve very low nutrient discharges through a variety of processes, primarily biological nutrient removal (BNR), physical separation, and chemical methods. Most technologies capable of removing both nitrogen and phosphorus utilize BNR, which relies on bacteria to transform nutrients present in wastewater. In BNR, bacteria are exposed to the influent from primary treatment. The selection of a BNR process should be based on influent flow and loadings, such as biochemical oxygen demand (BOD), nutrient concentrations, and other constituents, as well as target effluent requirements.
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Select species of bacteria can accumulate phosphorus, while others can transform nitrogen, and a few can do both. Achieving significant reductions in both nitrogen and phosphorus requires careful design, analysis, and process control to optimize the environment of nutrient-removing organisms. The uptake of nutrients and growth of microorganisms could be inhibited by a limiting nutrient, available carbon, or other factors, including oxygen levels. Some nutrient removal systems rely on two separate processes for nitrogen and phosphorus removal. In some cases, BNR is used to remove the majority of nitrogen and phosphorus, and then chemical methods are used to further reduce phosphorus concentrations. Mainstream nutrient treatment takes place within the typical plant process flow. However, sidestream treatment refers to liquid resulting from biosolids treatment (anaerobic digestion and dewatering) that is intercepted with an additional treatment goal—to remove nutrients from a concentrated stream and minimize mainstream impacts. Like mainstream nutrient treatment processes, sidestream treatment can also vary from biological to physical and chemical removal methods. Nitrogen Removal Nitrogen can be removed from wastewater through physiochemical methods, such as air stripping at high pH, but it is more cost-efficient to use BNR. Conventionally, this method utilizes the natural nitrogen cycle, which relies on ammonia-oxidizing bacteria to transform ammonia into nitrites (NO2-) after which nitrite-oxidizing bacteria form nitrates (NO3)—a process called nitrification. Other species of bacteria can transform these compounds into nitrogen, a harmless gas (N2)—a process called denitrification. Nitrification can occur in the
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aeration basin together with BOD oxidation, as they both require aerobic conditions. In contrast, denitrification takes place in an anoxic reactor with the nitrate providing the required oxygen. As denitrification occurs, nitrogen gas is produced and released safely into the atmosphere, where nitrogen gas is more abundant than oxygen. Nitrogen gas is inert and does not pollute the atmosphere. When performing biological nitrogen removal, it is important that the activated sludge has enough available carbon to sustain denitrification. The bacteria that mediate denitrification need carbon to build new cells as they remove nitrogen. This means that utilities must make decisions on how best to use the carbon for the combinations of nutrient removal/recovery, energy generation, and/or recovery of value-added nonnutrient products. The nitrogen removal rate is also dependent on the amount of time that sludge spends in the reactor (solids retention time), the reactor temperature, dissolved oxygen, pH, and inhibitory compounds. Optimal conditions differ for nitrification and denitrification, but both can be carried out simultaneously in the same unit if anoxic and aerobic zones exist. Some process configurations, such as oxidation ditches and sequencing batch reactors, combine nitrification and denitrification within a single tank, while others incorporate two separate stages. Nitrogen removal processes can also be broken down into two categories based on whether bacteria are suspended within the waste stream or fixed to media. Examples include integrated fixed film activated sludge (IFAS) and denitrification filters. A method of nitrogen removal that has gained favor over the past decade is deammoniContinued on page 40
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Continued from page 38 fication, a two-step process that avoids nitrate formation. Aerobic ammonia oxidation to nitrite occurs in the first phase, then nitrogen gas is produced through anaerobic ammonium oxidation, also known as Anammox, which is a biological process carried out by specialized bacteria that oxidize ammonia, and nitrite is used as an electron acceptor (oxygen source) under anaerobic conditions.
Phosphorus Removal Unlike nitrogen, phosphorus cannot be removed from wastewater as a gas. Instead, it must be removed in particulate form through chemical, biological, or hybrid chemical–biological processes, or nanoprocesses. Nano methods involve membranes and include reverse osmosis, nanofiltration, and electrodialysis reversal. Chemical methods (chem-P) typically utilize metal ions, such as alum or ferric chloride. These compounds bind with phosphorus and cause it to precipitate and be removed by sedimentation and filtration. Chemical methods are influenced by a number of factors, including the phosphorus species, choice of chemical, chemical-to-phosphorus ratio, the location and number of feed points, mixing, and pH. Enhanced biological phosphorus removal (EBPR, or bio-P) relies on phosphorus-accumulating organisms (PAOs) capable of removing phosphorus in excess of metabolic requirements. While many factors impact the EBPR process, the two most important requirements are availability of a readily biodegradable carbon source (food) and cycling of the PAOs between anaerobic and aerobic conditions. In the anaerobic zone, PAOs take up and store carbon. The energy required for this is obtained by releasing internally stored phosphorus. In the subsequent aerobic zone, the stored carbon is assimilated and the energy is used to uptake excess phosphorus. Consequently, the design and operation of EBPR systems must consider the availability of a readily biodegradable carbon source (such as volatile fatty acids) and the integrity of the anaerobic zone by eliminating dissolved oxygen and/or nitrate contributions from the influent, return streams, and backflow from the downstream aerobic zone. As with biological nitrogen removal, oxygen levels, solids retention time, and temperature play an important role in EBPR ef-
ficiency. It is common practice to add a standby chemical system to account for poor EBPR performance. Many existing biological nitrogen removal processes can be modified to remove phosphorus by adding an anaerobic phase. However, economic and environmental trade-offs exist, such as greenhouse gas production in the form of nitrous oxide, as well as increased energy demands. Nutrient removal techniques can also affect biogas production and dewatering. The dewatering process is negatively affected by bio-P. During anaerobic digestion, flow from the bio-P process can decrease the efficiency of dewatering and require additional polymer as a coagulant, particularly when there are fewer beneficial metal ions, such as iron and aluminum. From Removal to Recovery Beyond simply removing nutrients, WRRFs also can reclaim nutrients. Recovery not only prevents nutrients from entering waterbodies, but provides a supply of these essential resources. The most straightforward way of recovering nutrients is through biosolids. The EPA estimates that the approximately 16,000 WRRFs in the United States generate about 7 million tons of biosolids. About 60 percent of these biosolids are beneficially applied to agricultural land, with only 1 percent of crops actually fertilized with biosolids. However, generating solid fertilizer from biosolids is the most common method of nutrient recovery from wastewater. Wastewater operations that have adopted the “principles of becoming a utility of the future” are using the nutrient removal process to produce marketable products beyond simple biosolids, including nutrients, energy, electricity, and vehicle fuels. Phosphorus used for fertilizer is a finite resource, with some estimating that demand will outpace supply within the next
Nutrient removal is an essential part of wastewater treatment to help prevent algal blooms, as shown in this 2011 satellite photo of an especially severe case in Lake Erie. (Credit: MERIS/NASA; processed by NOAA/NOS/NCCOS)
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century. In a similar vein, ammonia is produced via the Haber-Bosch process, which consumes natural gas (a nonrenewable resource), is an energy-intensive process, and is associated with greenhouse gas emissions. Interest in recovering nutrients from wastewater has increased over the last decade. However, the maturity of nutrient recovery technologies varies, and each has its advantages and disadvantages. Sidestream treatment of sludge and sludge liquor, where nutrients are more concentrated, is generally the preferable target for nutrient recovery, but resource recovery complexity can vary widely depending on local conditions. In addition to nutrients, there are other types of products that can be recovered, such as metals, heat, and potable or drinking water, which may bring financial rewards and benefits to help offset utility costs. These are some nutrient-based and other resources that can be recovered at a WRRF: ! Solid fertilizer from biosolids o Land application of biosolids recycles nitrogen, phosphorus, carbon, and other macronutrients. o Soil blends and composts are potential phosphorus recovery products. o Incinerator ash is also a source of phosphorus for recovery. ! Solid fertilizer from the treatment process
o Struvite precipitation and recovery. By this method, both phosphorus and ammonium can be simultaneously recovered, producing a high-quality fertilizer from some sidestream systems. o Other methods of phosphate precipitation such as brushite are also becoming common. ! Water reuse o Irrigation with reclaimed water can have some nitrogen and phosphorus benefits. ! Chemical recovery o Structural materials can be obtained from carbonates and phosphorus compounds. o Proteins and other chemicals, such as ammonia, hydrogen peroxides, and methanol, can be recovered. o Solids can be stored for future mining. A Roadmap to Nutrient Recovery With the complexity of nutrient removal and recovery alternatives available, utility staff may wonder how to move forward to address current needs or plan for future impacts of nutrient limits. The Water Environment Federation (Alexandria, Va.) has released a Nutrient Roadmap to support the movement toward smarter and sustainable nutrient management in the context of each WRRF’s specific regulatory climate and stakeholder preference. The
roadmap provides a straightforward, high-level framework for planning, implementing, and evaluating different steps of a net-zero nutrient discharge strategy and can be found at www.wef.org/nutrientroadmap. Note: The information provided in this article is designed to be educational. It is not intended to provide any type of professional advice including without limitation legal, accounting, or engineering. Your use of the information provided here is voluntary and should be based on your own evaluation and analysis of its accuracy, appropriateness for your use, and any potential risks of using the information. The Water Environment Federation (WEF), author, and the publisher of this article assume no liability of any kind with respect to the accuracy or completeness of the contents and specifically disclaim any implied warranties of merchantability or fitness of use for a particular purpose. Any references included are provided for informational purposes only and do not constitute endorsement of any sources.
Barry Liner, Ph.D., P.E., is director of the Water Environment Federation (WEF) Water Science & Engineering Center. Sam Jeyanayagam, Ph.D., P.E., BCEE, is chair of the WEF Nutrient Roadmap publication task force. !
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F W R J
Wastewater Treatment Cost Reduction: Stabilizing Chlorine Demand in Wastewater Effluent Charles Nichols, David Carr, Mark Lowenstine, and Craig Fuller
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he operation of wastewater treatment facilities requires significant expense, especially when the facilities must provide public access reuse or advanced wastewater treatment-quality water. The highest expenses are normally for power, operations, equipment maintenance, and chemicals. If the facility utilizes sodium hypochlorite for primary and residual disinfection, these are often the highest chemical costs. A new low-cost addition at Polk County’s Northeast Regional Wastewater Treatment Facility (Facility) has lowered the consumption of disinfection chemicals, while maintaining a more constant residual. The Facility has been able to stabilize chlorine demand and lower the total chlorine demand, while not significantly modifying the existing infrastructure. Additional benefits include lowered maintenance costs and lower algal growth. The small addition to the Facility is the Environmental Control Company’s floating balls, also known as shade balls, to cover the chlorine contact basins (see photo).
mgd, with peak month averages approaching 3 mgd. The wastewater effluent from the Facility has average effluent qualities of 1/0.5/4/1.5 mg/l as defined previously. The contribution of ammonia as nitrogen averages approximately 0.1 mg/l, which is especially important to note due to its high consumption rate of chlorine. During the past two years, the Facility has had an average total chlorine use of approximately 18.2 mg/l +/- 7.2 mg/l (1.96 sigma), with an effluent residual averaging 3 mg/l. This equates to a consumption of 15.2 mg/l with greater than 50 percent variability. Removing the months of January and February 2013 due to assisting a facility owned by others that was known to have higher than typical ammonia and CBOD5 levels, the average total chlorine use was approximately 17.5 mg/l +/- 5.9 mg/l. This would equate to a consumption of 14.5 mg/l with 47 percent variability over a two-year period. Fig-
Charles Nichols is a regional wastewater treatment supervisor, David Carr is a wastewater treatment plant operator, and Mark Lowenstine is the water and wastewater manager with Polk County Utilities in Winter Haven. Craig Fuller, P.E., is a senior water and wastewater engineer at AECOM in Bartow.
ure 1 shows the monthly average chlorine use as a dosage (mg/l) before the shade balls were installed. The months of January and February 2013 were removed due to an unusual event when the Facility treated flow from another source that required higher than normal chlorine utilization. With chlorine demand and variability so high and with minimal inorganic demand, Polk
Chlorine Demand Before Shade Balls The Facility is an existing wastewater treatment facility rated for an average annual treatment capacity of 6 mil gal per day (mgd), capable of treatment with effluent discharging below 5/5/5/3 mg/l as five-day carbonaceous biochemical oxygen demand (CBOD5), total suspended solids (TSS), total nitrogen (TN), and total phosphorous (TP). The Facility currently treats an annual average daily flow of 2.5
Figure 1. Chlorine Dose at Facility Without Shade Balls
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County decided to investigate options for decreasing the total chlorine demand. The County considered installing an overhead shade at the Facility to decrease the temperature and ultraviolet (UV) consumption of chlorine. The County has installed an overhead shade at the Northwest Regional Wastewater Treatment Facility (Northwest Facility) with good results, and the County desired to implement similar measures throughout its service area. At the Facility, the chlorine contact basins had a much larger footprint than the Northwest Facility, and the installation of an overhead shade would have been much more expensive. The County found a less invasive option by contacting a neighboring utility. The City of Lakeland (City) had been utilizing the floating balls to limit algal growth in a basin within the County. The City had decided to decommission the use of the balls, and the County requested the use of the balls for trial purposes. By inserting the floating balls into the chlorine contact at the Facility, it had hoped to accomplish similar results to the overhead shade, but found that additional benefits were gained and results were better than expected.
culations for evaporation, the average amount of chlorine lost due to evaporation can be estimated. The calculations assume an average concentration in the contact basin of 8 mg/l, a water temperature of 27°C, and an average wind speed of 10 mi per hour (mph), which are similar conditions to the average in Davenport. The chlorine average loss due to evaporation is estimated to be approximately 1.1 mg/l. It should be noted that this calculation assumes the evaporation losses of water to be relatively inconsequential compared to the losses of chlorine (Sung, H.M.); it should also be noted that the main contributor to the losses is wind. Although temperature plays a role, it is relatively constant. While vapor pressure of chlorine increases at elevated temperatures, the solubility capabilities of water increases. If the water temperature increases 10°C (a greater variability than exists in the effluent), the losses only increase by 0.5 mg/l. However, if the wind speed increases by 10 mph, the losses increase by 0.8 mg/l. The following equation shows example calculations:
Chlorine Calculations The County’s chlorine use at the Facility is attributable to disinfection and maintenance use. Disinfection chlorine consumed in a contact basin is attributable to the initial demand (CBOD5, inorganics), evaporation losses (offgassing), UV losses, and losses due to oxidation of unwanted material growth in the basin. The initial demand was already minimized through treatment process optimization in the chlorine contact basin, but the other losses were still affecting the operational stability of the Facility. The initial demand can be directly measured by comparing the dose to the residual immediately after dose. Before the shade balls were put into the Facility, the average dosage was desired to be approximately 13.5 mg/l, leaving an 8 mg/l just after dose. The target set point was elevated due to changing field conditions to leave an effluent residual of 3 mg/l, which resulted in an actual average dosage of approximately 17 mg/l. The average instantaneous chlorine demand was calculated to be approximately 5.5 mg/l under normal conditions. It should be noted that the maintenance amount averages about 0.5 mg/l for cleaning other parts of the plant, such as the tertiary filters and clarifiers. The next type of loss that can be estimated is evaporation. Utilizing Raoult’s Law of partial pressures and Off-Site Consequences Analysis (OCA) Guidance (Kirk-Othmer), which is a modified version of Mackay and Matsugu’s cal-
E = Evaporation rate in lb/min U = Wind speed in m/s M = Molecular weight of compound A = Area of exposed liquid surface in ft2 Pv = Partial vapor pressure of compound evaporated T = Absolute temperature in kelvin To calculate the partial pressure using Raoult’s Law, the vapor pressure of chlorine at the known temperature must be considered. Utilizing the Air Liquide Encyclopedia, the pure vapor pressure is 7 bar (5,250 mmHg). With a mol fraction of 2.03 X 10-6, the partial pressure of chlorine gas is approximately 0.011 mmHg. The other losses (UV and oxidation of unwanted materials) can be grouped together as they are interrelated. The UV and nitrates present in effluent wastewater cause growth to occur, while the UV also reacts with the chlorine to decrease the residual. From the previous equations and known information, the following can be deduced: Total chlorine average: Maintenance use: Initial/instantaneous demand: Evaporation losses: Effluent residual: Additional losses: Total Chlorine Consumption:
17.5 mg/l 0.5 mg/l 5.5 mg/l 1.1 mg/l 3.0 mg/l 7.4 mg/l 14.5 mg/l
This leaves an average of approximately 7.4 mg/l of chlorine consumed by UV or oxidation of material growth. Both UV consumption and the evaporation consumption are highly variable and depend on atmospheric conditions.
Theoretical Calculations for Shade Ball Addition The addition of the shade balls had some apparent benefits. The majority of the chlorine contact basin liquid was shaded from sunlight, resulting in lower temperatures and lower UV light exposure. Reviewing literature from the manufacturer, the balls would cover 91 percent of the surface where they are applied, effectively allowing only 9 percent of the water to be exposed to UV light. The added benefit was that with only 9 percent of the water surface being exposed, there was significantly less area for the chlorine to off-gas from the liquid where the balls are present. This would notably decrease the variability of evaporation losses and decrease the consumption of chlorine. Based on the area exposed and the decreased chlorine demand, it is estimated that the average chlorine losses from evaporation should decrease from approximately 1.1 mg/l to 0.2 mg/l, or a reduction of 0.9 mg/l in chlorine demand. The UV and other materials demand should decrease by at least the same level. Assuming that the UV losses were decreased by the fractional area where the shade balls were added, it is expected that the UV demand will drop from 7.4 mg/l to 1.9 mg/l, or a reduction of 5.5 mg/l in chlorine demand. Adding the chlorine consumption savings together, it is estimated that the shade balls would save approximately 6.4 mg/l of chlorine. This would be a drop in total chlorine consumption from 14.5 mg/l to 8.1 mg/l (excluding the effluent residual). Decreasing outside demands, such as UV and evaporation, should also decrease the variability of the chlorine demand. As demonstrated previously, the chlorine demand had a variability of 47 percent within two standard deviations. If the variability of demand decreases by the amount of liquid exposed, the theoretical variability in chlorine demand should drop to 12 percent of the demand value. That should result in a chlorine demand decrease from 14.5 +/- 5.9 mg/l to 8.1 +/1.5 mg/l, excluding effluent residual.
Shade Ball Results At the start of September 2013, the shade balls were installed and it was almost immediately noted that the chlorine residual stayed much Continued on page 44
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Continued from page 43 more constant. Due to the tighter controls, the effluent residual is now 4 mg/l rather than the expected 3 mg/l and the dose set point residual is now 5.5 mg/l with a dosage of 11 mg/l. From September 2013 through the end of December 2013, the chlorine use and flow was tracked to determine the demand. Removing the 4.0 mg/l average residual from the calculations, the total chlorine demand is now 7.3 +/- 1.0 mg/l for the fourmonth period, including 5.5 mg/l of instantaneous chlorine demand. The results were better than calculations predicted, but it is possible that a 12-month period will have a closer correlation to the expected 8.1 +/- 1.5 mg/l. It is also possible that the majority of the evaporation and UV exposure was occurring where the shade balls were added. The following is the estimated breakdown of chlorine uses after the shade ball’s addition:
Figure 2. Chlorine Dose at Facility With and Without Shade Balls
Figure 3. Chlorine Dose at Southwest Facility With and Without Shade Balls
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Total chlorine average: Maintenance use: Initial/instantaneous demand: Evaporation losses: Effluent residual: Additional losses: Total Chlorine Consumption:
11.3 mg/l 0.5 mg/l 5.5 mg/l 0.2 mg/l 4.0 mg/l 1.3 mg/l 7.3 mg/l
Figure 2 illustrates the monthly average chlorine use as a dosage since the shade balls were added. The average savings of 6.2 mg/l of chlorine (17.5 mg/l versus 11.3 mg/l consumption) represents a daily savings of nearly 129 gal per day (gpd) of chlorine solution (12 percent wt/vol). At a low cost of $0.70/gal, this represents a yearly savings of nearly $33,000. The balls have a 10-year warranty and are replaced if there are any issues within the life of the ball. This would represent a chemical savings of $330,000 over a 10-year period, even if the chlorine cost did not increase and the influent flow remained unchanged. The improved operational performance at the Facility is as important as the cost savings. The shade balls have tightened the chlorine contact control capability, leaving only 17 percent of the previous deviation in chlorine demand. This is a decrease in deviation from +/- 5.9 mg/l to only +/- 1.0 mg/l, increasing the operation staff’s confidence in the Facility to provide water with adequate chlorine residual. It has also been noted that the maintenance on the chlorine contact basins has decreased. Previously, a tank had to be taken down for preventative maintenance and scrubbed one day per month to remove iron deposits, algae growth, and dirt that had accumulated. The time it took to scrub a tank was approximately four hours. The tanks are now taken down one day every two and a half months, but do not Continued on page 46
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Continued from page 44 need to be scrubbed. They are also taken down to remove dirt or sand deposits from the floor that may have blown in, and the time has decreased to only about one hour of work. This represents a decrease of about 43 hours/year for maintenance. At a loaded cost of roughly $25/hour, that represents a yearly savings of over $1,075 and, more importantly, it allows staff to complete tasks that may be of higher priority. The cost to purchase the shade balls would have been only $4,700, or $2.45 per sq ft of surface area. To keep the shade balls within the basin, a vertical grate was installed in each channel of the chlorine contact basin upstream of the overflow weir. The grate allows water to flow through it, limiting excessive forces and keeping the balls in their floating position. The total cost would have been less than $10,000 for all equipment and installation if performed by a contractor. The cost savings in chlorine alone pays for the ball installation in less than one year. With the positive results observed at the Facility, Polk County implemented the use of shade balls at the Southwest Regional Wastewater Treatment Facility (Southwest Facility) at the start of 2014. The total average chlorine
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dosage at the facility was 18.8 mg/l from Jan. 1, 2012, through Dec. 31, 2014. After adding the shade balls, between Jan. 1, 2014, and Sept. 30, 2014, the average chlorine dosage had dropped by 1.0 mg/l to 17.8 mg/l. In late September 2014, additional changes were made to the biological treatment process, changing how the return activated sludge (RAS) was sent back to the activated sludge process at the Southwest Facility. The RAS changes resulted in 1.3 mg/l less chlorine demand for a total savings of 2.3 mg/l. The chlorine dosage at the Southwest Facility averaged 16.5 mg/l between Oct. 1, 2014, and Dec. 31, 2014. Figure 3 depicts the savings, along with the deviation in demand for those periods. Note that in the first month of 2015, the biological treatment process was notably changed at the Southwest Facility, altering anoxic return and providing for an environment that would allow simultaneous nitrification/denitrification. The result of the changes was a decrease in chlorine demand of an additional 2.3 mg/l. The resulting monthly average chlorine dosage decreased from 18.8 mg/l to 14.2 mg/l between 2012 and 2015. The total decrease in chlorine demand at the facility resulted in a savings of approximately 61 gal/day or an annual savings of $15,600.
May 2015 • Florida Water Resources Journal
Acknowledgment The authors wish to thank Jake Rohrich, operations director for Polk County Utilities, for his support of this project. Without him, the investigative work and installation would not have been possible.
References • Northeast Regional Wastewater Treatment Facility Staff – Jason Jennings, Jeff Goolsby, and James Hickman. • Southwest Regional Wastewater Treatment Facility Staff – Todd Potter, William Altman, James Hall, William Mack, and Cynthia Sammons. • Kirk-Othmer, Encyclopedia of Chemical Technology, 4th ed., Wiley, New York, 1991. • Mackay, D. and Matsugu, R., “Evaporation Rate of Hydrocarbon Spill on Water and Land,” Canadian Journal of Chemical Engineering, p. 434, Vol 5., 1973. • Sung, H.M., “Accidental Releases Analysis for Toxic Aqueous Solutions,” Trinity Consultants, 1998. • Air Liquide Gas Encyclopedia, Chlorine/Dichlorine Gas, Vapor Pressure Graph, 2013. !
Operators: Take the CEU Challenge! Members of the Florida Water & Pollution Control Association (FWPCOA) may earn continuing education units through the CEU Challenge! Answer the questions published on this page, based on the technical articles in this month’s issue. Circle the letter of each correct answer. There is only one correct answer to each question! Answer 80 percent of the questions on any article correctly to earn 0.1 CEU for your license. Retests are available. This month’s editorial theme is, Operations and Utility Management. Look above each set of questions to see if it is for water operators (DW), distribution system operators (DS), or wastewater operators (WW). Mail the completed page (or a photocopy) to: Florida Environmental Professionals Training, P.O. Box 33119, Palm Beach Gardens, FL 33420-3119. Enclose $15 for each set of questions you choose to answer (make checks payable to FWPCOA). You MUST be an FWPCOA member before you can submit your answers!
___________________________________________ SUBSCRIBER NAME (please print)
Article 1 ________________________________________ LICENSE NUMBER for Which CEUs Should Be Awarded
If paying by credit card, fax to (561) 625-4858 providing the following information:
___________________________________________
Wastewater Treatment Cost Reduction: Stabilizing Chlorine Demand in Wastewater Effluent Charles Nichols, David Carr, Mark Lowenstine, and Craig Fuller (Article 1: CEU = 0.1 WW)
1. Including ALL months during the two years preceding this evaluation, a. average Northeast Regional Wastewater Treatment Facility (NE Facility) total chlorine dosage was 15.2 mg/l. b. average NE Facility chlorine demand was 18.2 mg/l. c. NE Facility chlorine demand variability exceeded 50 percent. d. average NE Facility effluent residual chlorine exceeded 3.0 mg/l. 2. Theoretically, it was anticipated that addition of the shade balls would reduce NE Facility chlorine losses by evaporation by ___ mg/l. a. b. c. d.
0.2 0.5 0.9 1.1
3. Which of the following is not listed as a benefit of shade balls at the NE Facility? a. Reduction in trihalomethane formation potential b. Reduction in chlorine purchase cost c. Reduction in chlorine contact basin maintenance d. Reduction in the variability of chlorine demand 4. The greatest reduction in chlorine dosage at the Southwest Regional Wastewater Treatment Facility resulted from a. b. c. d.
the addition of shade balls. process changes involving return activated sludge. a switch from liquid to gas chlorine supply. a reduction in plant flow.
5. The idea to use shade balls at the NE Facility chlorine contact chamber originated with a a. b. c. d.
successful experiment installing overhead shade for the chamber. neighboring utility. marketing call. trade journal article.
(Credit Card Number)
Earn CEUs by answering questions from previous Journal issues!
___________________________________________
Contact FWPCOA at membership@fwpcoa.org or at 561-840-0340. Articles from past issues can be viewed on the Journal website, www.fwrj.com.
(Expiration Date)
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May 2015 • Florida Water Resources Journal
Florida Water Resources Journal • May 2015
49
New Products The PekaSys Bubbler from Anua batches treatment in cycles, including aerobic and anaerobic steps, to clean water and reduce total nitrogen for residential and commercial applications. As a sequencing batch reactor, it allows the treatment steps to occur in the same chamber. Smart controls automatically adjust aeration, which optimizes treatment, saves energy, and prevents sludge bilking. Flexible tank configurations include retrofitting to existing tanks or failed systems. Its single treatment chamber saves space. It provides total suspended solids of less than 10 mg/l and greater than 50 percent total nitrogen reduction. (www.anua-us.com)
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The bioForce liquid from Chempace Corp. contains a blend of highly active microorganisms effective in degrading a wide range of organic waste found in many applications, such as household and institutional, wastewater treatment, and odor control. The bacteria consortia have been chosen for their accelerated degradation capabilities of organic compounds, such as grease, fats, proteins, starches, sugar, and cellulose, Regular use lowers biochemical oxygen demand and chemical oxygen demand. It controls odors through a dualodor control elimination package, as the microbes digest the odor-casuing substitutes while the fresh fragrance deodorizes the area of use. It is nontoxic and biodegradable. (www.chempace.com)
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The drivers app from Clear Computing, which runs on Apple and Android devices, gives drivers a real-time route list for service stops and work orders, with all the information needed to complete and update the status of each job. Included are voice directions from the current location for each stop, maps, and update forms for key operational fields, including quantity, units serviced, and start/end times. It includes customer email notification of service completion and generates reports for profit and loss by stop. Updates flow immediately to the back office with completion date and time. Service verification statements are available for emailing to customers. (www.clearcomputing.com)
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Forbest Products Co. created the FBPIC3688 pan-and-tilt pipe inspection camera system that allows users to take panorama pictures, with remote directional control for over 20,000 continuous hours. It comes with 400 ft of 9-mm fiberglass cable and a reel with meter counter and 2-in. waterproof 360/180-degree pan-tilt high-resolution color camera head with zooming that can work under the water no more than 30 meters. The heavy-duty waterproof control box includes a 10-
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May 2015 • Florida Water Resources Journal
in. LCD color screen with USB and built-in SD card for recording. The built-in rechargeable battery pack lasts about three hours. (www.forbestusa.net)
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IM-Series injection-molded septic and potable water tanks from Infiltrator Systems have integral heavy-duty lids, structurally reinforced access ports, reinforced structural ribbing and fiberglass support posts to provide additional strength. They require no special installation, backfill, or water filling procedures. The tanks provide strength in a two-piece design that efficiently nests for reduced shipping costs and local assembly. Available septic and pump tanks include the IM-1530 and IM-1060 septic tanks, and the IM-540 pump tank. Potable water tanks are NSF 61 certified, designed for buried water tank applications, and available in 552, 1,287, and 1.787-gal capacities. (www.infiltratorsystems.com)
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The JetScan Mini video nozzle from Envirosight can be deployed in pipes from 6 to 10 in. in diameter and gives sewer cleaning crews visual feedback to select the proper tools, troubleshoot backups, identify buried safety hazards, and document successful cleaning. The device captures HD video footage from underground pipes for offline tablet viewing. It records up to 8 hours of 720 pixel HD MPEG
video to an onboard 32 GB SDHC memory card, which is easily removed to view video on an iPad or other DSHC-compatible device. (www.envirosight.com) !
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The Pipemaster, a manually operated, highpressure hose rotating system from Hammelmann Corp. is used to remove both soft and very hard deposits from the insides of pipes and pipelines, including those with bends and vertical sections. As an alternative to self-rotating nozzles, rotary action is achieved by rotating the high-pressure hose. A high-pressure supply hose line is fixed between the pump and the rotary joint on the rotating unit. A second hose is connected to the rotary joint and runs via the deployment unit into a protective base to the positioning device. The rotation of the second high-pressure hose around its longitudinal axis is affected by a chain drive from a pneumatic motor to the rotary joint. The rotation speed can be adjusted by throttle check valves. Actuating the control lever of the unit causes the hose to start rotating, which produces the deployment motion. (www.hammelmann.com)
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The Depth Ray liquid level monitoring and control system from Eldredge Equipment Services provides continuous display and control of tank liquid levels during loading and unloading using contact, noncontact radar, and ultrasonic technology. Systems can be used in vacuum/pressure and nonpressure tanks from 4 to 66 ft. They can be powered by 12-volt DC, 120-volt AC or battery/solar. Installation doesn’t require tank entry. The digital LED display is mounted in a NEMA 4 enclosure for outside or cab mounting. It has controls for opening and closing valves or sounding alarms. A 500-ft-range wireless remote control unit is available. (www.depthray.com)
Florida Water Resources Journal • May 2015
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News Beat February rainfall was above average across much of the South Florida Water Management District (SFWMD), with a significant portion falling the last day of the month. Significantly, the Kissimmee basins continued their trend of above-average rainfall feeding Lake Okeechobee. Rainfall for the month north of the lake was about double the historical average for February. The two basins received 5.13 and 4.20 in. of rainfall respectively, representing 216 percent and 184 percent of average for the month. “Above-average Kissimmee rainfall continues to contribute to the already high lake stages,” said Jeff Kivett, SFWMD division director of operations, engineering and construction. “Operations continue moving water south of the lake, and the District has increased pumping at temporary water storage areas where possible.” District-wide, 3.07 in. of rain fell during February, representing 135 percent of average, or 0.80 in. above average. February 28 saw a District-wide average of about 1 in., or about a third of the month’s rainfall. Areas of eastern Palm Beach County experienced local maximums of 10 in. that day. Lake Okeechobee also received above-average rainfall, with 2.94 in. of direct rainfall, representing 138 percent of average, or 0.81 in. above average. The lake stood at 14.71 ft national geodetic vertical datum (NGVD) today, which is 0.20 ft above its historic average for this time of year and nearly a ft higher than this time last year. Most of the remainder of the District also saw above-average rainfall in February. Martin and St. Lucie counties, among the wettest areas of the 16county district, saw 4.65 in. of rain, representing 185 percent of average, or 2.14 in. above average. The Southwest Coast and East Caloosahatchee received 119 percent and 105 percent of average rainfall, respectively. Big Cypress Preserve was one of the few areas to receive below-average rainfall, with 1.70 in. representing 77 percent of average, or 0.51 in. below average.
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The St. Johns River Water Management District is partnering with the city of Vero Beach on a project to help improve water quality in the Indian River Lagoon. The Vero Beach Hybrid Septic Tank Effluent Pumping System (STEP) project will reduce nutrients flowing to the lagoon. The STEP project will divert septic system effluent, currently entering the groundwater along the Indian River Lagoon, to a central facility for treatment, preventing up to 40,500 pounds of nutrients per year from entering the groundwater. By reducing septic effluent and associated nutrients from entering the groundwater, less nutrients flow to the lagoon from septic systems near the shallow estuary. Continued on page 54
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May 2015 • Florida Water Resources Journal
C FACTOR Thomas King President, FWPCOA
T
he FWPCOA held its spring short school March 16-21 in Ft. Pierce. I was honored to be among those giving back to our industry by teaching and passing on some of our mentionable experiences. We will forever keep the unmentionable ones to ourselves. The school’s utility maintenance class is continuing to grow in popularity, and David Patchuki has now added a level II certification. The hands-on alignment training was one of the many impressive lessons offered. More than a few of the students commented about the added value they would take back to their utility. I will also take this opportunity to mention that Dave is the new state chair of the Utility Maintenance Committee. Classes on water distribution, stormwater, wastewater collection, utility management, backflow preventer training, backflow preventer repair, electrical basics, and reclaimed water were also offered. I was once again impressed by the dedication of the instructors—they are the volunteers that make FWPCOA work. Many of those instructors were taking their vacation time to teach classes to the new generation of utility managers. We had approximately 240 students and greatly appreciate those utilities that sent them. I spent some time talking to the students as we passed each other in the hall. I was glad to see them exchanging ideas and “talking shop.” I have always said the students go back to their utilities with more than just the new knowledge of the classes they attend; we also teach a philosophy of dedication and caring that we hope will guide the environmental caretakers of the future. The students were all noteworthy, but my space is limited. I met Darin Lajoie from Wellington who has worked for utilities for over 20 years and now has a diversified background. I spoke with Bill Peters from Palm Bay, a maintenance superintendent, who was interested in all factions of the utility management class. Chris Woolweaver from the Ft. Lauderdale area took the stormwater class striving to get all the certifications available to help him move up in the field. Of course, Brad Hayes from FWEA was there with his troops. Brad is never at a loss for words and is one of those managers who pushes his workers to attend classes in order to better themselves and their utility. I also spent some time with young and energetic instructors teaching for their first or second time at a short school. Kendra Phillips from Hillsborough County Utilities is just what the industry needs. Full of ideas and willing to share her knowledge while learning what we all get
Anatomy of a Short School from teaching, Kendra is a good example of the new generation of leaders that will take over from us tired old dinosaurs. Thanks from all of us at FWPCOA to those utilities who loan us their talented supervisors and staff members to spend time teaching. I can’t mention a short school without talking about Shirley Reeves. Shirley worked through a bad case of a cold, the flu, or the black plague to put up with the thousands of questions that came from students and instructors. Some were good questions, some were just whining, and some came from people in the wrong class (like the lady looking for the tax seminar). Thanks to Shirley, we continue to have an education office that runs like a well-oiled machine. As for me, I truly love teaching. I get so much from students who enjoy the learning experience of an FWPCOA short school. I strive to infuse a sense of environmental responsibility into those students who attend my classes. I have spent many a Patron-induced night of writing course material and looking for videos to match. Actually, any ex-
cuse to drink tequila works for me. A frequent comment from many students was not getting their books early enough. I know that many utilities have students who still have books from previous years who could share them until the new students attend class. At my office I have set up a working library of old training manuals for the employees to use to study, and I would encourage other utilities to do the same. Having a book a few weeks prior to the class would help the students and encourage an exchange of knowledge before they attend the short school. Our next big state-sponsored event will be the fall short school. There are scholarships available that cover the cost of the short school and expenses up to $800. Each year, your region can award a scholarship (Pat Robinson Award) to a deserving member. If you know someone to be nominated, or believe you are that person, please contact your region director. If you are interested in a great learning environment shared by others in our industry, I hope to see you there. !
Florida Water Resources Journal • May 2015
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New Products Continued from page 52 The project will save residents thousands of dollars by connecting their septic tanks to a central sewer system, as compared to the costs of traditional septic-to-sewer conversion projects. Residents will be allowed to keep their septic drainfields in place in the event of temporary power outages that would impact the STEP pumping system.
"Vero Beach has for years been interested in promoting and improving water conditions in the lagoon," said Vero Beach Vice Mayor Jay Kramer. "However, when it came time to look at the costs of removing septic systems from the river, the community was concerned about the high costs. The STEP system really saved us; we can now be environmentally active while keeping the costs down for the community."
According to William Tredik, leader of the District's Indian River Lagoon Protection Initiative, "Reducing nutrient inputs from all sources is critical to the recovery and future health of the Indian River Lagoon, Groundwater is continually entering the lagoon and improvements that reduce the flow of nutrients to the lagoon from groundwater are an important part of the overall solution." The total cost of the project will be $885,000, with the District providing $292,050 of the funding.
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The Miami-Dade Water and Sewer Department (WASD) has awarded Woolpert a fiveyear contract, with one five-year option to renew, to provide consulting services relating to capacity management, operations, and maintenance (CMOM) programs. Woolpert will work with WASD to review, modify, and develop the CMOM plans and programs as required by the U.S. Environmental Protection Agency (EPA) Region IV’s consent decree. Woolpert’s CMOM programs will take into account the vulnerability of the facilities to climate-change impacts such as sea level rise, storm surge, wind, and flooding. Woolpert will also ensure that the programs and plans are consistent with EPA’s guidance and are completed and submitted within the specific deadlines on the consent decree.
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Gov. Rick Scott has announced the reappointments of Charles “Chuck” Drake and Frederick “Fred” Roberts Jr. to the St. Johns River Water Management District. Drake, 56, of Orlando, is the vice president and a hydrogeologist with Tetra Tech Inc. He currently serves as a member of the National Ground Water Association and previously served as an executive committee member for the American Institute of Professional Geologists. Drake received his associate’s degree from Valencia Community College and his bachelor’s degree from the University of Florida. He is reappointed for a term beginning March 27, 2015, and ending March 1, 2019. Roberts, 36, of Ocala, is an attorney with Klein and Klein LLC. He currently serves as the vice chair of the College of Central Florida Foundation board of directors and the chair of the Boys and Girls Club of Marion County Board of Directors. Roberts received his bachelor’s degree from the University of Florida and his law degree from the Stetson University College of Law. He is reappointed for the same term as Drake. The appointments are subject to confirmation by the Florida Senate. !
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May 2015 • Florida Water Resources Journal
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EQUIPMENT & SERVICES DIRECTORY Showcase Your Company in the Engineering or Equipment & Services Directory Contact Mike Delaney at
352-241-6006 ads@fwrj.com
CLASSIFIEDS Positions Av ailable
WASTEWATER PLANT SUPERVISOR
Utilities Treatment Plant Operations Supervisor
$54,099 - $76,123/yr. Assists in the admin & technical work in the mgmt, ops, & maint of the treatment plants. Class “A” Water lic. & a class “C” Wastewater lic. req. with 5 yrs supervisory exp.
Utilities Treatment Plant Will Call Operator
$18.29-$28.38/hour. Part time. Must have passed the C drinking water or wastewater exam. Apply Online At: http://pompanobeachfl.gov Positions are open until filled. E/O/E
Town of Oakland UTILITY DISTRIBUTION TECHNICIAN I The Town of Oakland is recruiting for a full-time Utility Distribution Tech. 1. Requires HS diploma/equivalent, valid FL CDL class "B" license, Level 3 FDEP Water Distribution License. Other equivalent combinations of education, training and experience in Public Utilities or Public Works operations will be considered. Three years work exp. a plus. Open until filled. Compensation commensurate with experience. Send resume to HR Director Tonna Duvall at: tduvall@oaktownusa.com or dial direct 407.656.1117 x2102. EOE; M/F/D/V; DFWP
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The City of Lakeland is seeking a Wastewater Plant Supervisor. The Salary is $44,803.20 - $69,513.60 annually (DOE). This is skilled and technical work in the operation and maintenance of the City’s wastewater treatment plants. Requires a high school diploma from an accredited school or a G.E.D. and three (3) years of wastewater plant operations experience. Must possess and maintain a state of Florida Class “B” wastewater plant operator certification. Continuous – Position may close at any time without notice. Applicants must complete an online application at: http://www.lakelandgov.net/ employmentservices/employment-services/job-opportunities
Field Inspector 1
Pinellas County Government is seeking to hire two “Field Inspector 1” candidates to conduct cross-connection inspections. Must possess at least 2 years experience in cross-connection control and possess and maintain a valid Florida Driver’s License. Highly desirable: Current certificate from an approved training facility as a "Reclaimed Water Field Site Inspector", and 1 year experience as a cross connection inspector or backflow prevention assembly tester. Apply by: May 9, 2015. To apply visit: https://Employment.PinellasCounty.org. Ph: 727-464-3367. EOE/AA/ADA/DFW/VP. Certain service members and veterans, and the spouses and family members of the service members and veterans, receive preference and priority in employment by the state and are encouraged to apply for the positions being filled.
City of Tampa Engineer II
PUMP MECHANIC & FIELD TECHNICIAN
The City of Tampa is currently recruiting for an Engineer II.
VERTICAL TURBINE-HORIZONTAL SPLIT CASE-END SUCTION PUMPS TITUSVILLE SALES SERVICE & REPAIR CENTER/ 386-690-1075
Primary responsibilities include: performing professional level work in engineering in the Engineering Division of the Water Department.
May 2015 • Florida Water Resources Journal
Apply online http://apps.tampagov.net/appl_personnel_job_openings/job_ detail.asp?posting_id=3462
City of Largo WASTEWATER COLLECTION TECHNICIAN I Progressively intensive manual labor work in the collection of wastewater. An employee in this position is responsible for performing a wide variety of skilled to semi skilled tasks, and performing any other work in connection with the sanitary wastewater collection system MINIMUM QUALIFICATIONS: High School Diploma or General Education Diploma (G.E.D.); Class "B" CDL with Tanker endorsement (CDL),FWPCOA Wastewater Collections "C" Certification; CPR/First Aid Training Full time, excellent benefit package Online applications only: www.largo.com/jobs
Director of Public Works & Utilities The City of Newberry seeks an enthusiastic, dynamic leader for its Utility & Public Works department that has a strong background in utility & public works operations. Position is responsible for the City’s electric, water, and wastewater utilities (1,900 customers), and streets & drainage, solid waste, mosquito control, and cemetery. Ideal applicant must have ten (10) or more years of progressively responsible related experience in a managerial or leadership capacity within public utilities or utility enterprises. Applications and full job description are available online at www.ci.newberry.fl.us or call 352-472-2161 ext 112.
Wastewater Plant Operator C License Marathon, Florida Keys Category: Full-Time Description: This position is responsible for wastewater treatment plant operation and process control data collection and reporting, ensuring that the plant operates within the required State of Florida Department of Environmental permit standards. Miscellaneous: Email application/resume to HR@ci.marathon.fl.us or fax to 305-289-4143. See website for full description: www.ci.marathon.fl.us
Licensed Water Plant Operator The North Springs Improvement District is seeking for Water Plant Operators. Must possess Class C or higher FL Drinking Water license. Trainees with sufficient education & training may be considered . Please email Mimi Ortega at Mireyao@nsidfl.gov with your application.
Positions Wanted PHILIP LEON – Holds a Florida dual license, B Water and C Wastewater with 14 years experience. Prefers the Tampa Bay area, Brandon, Lakeland, Plant City but is willing to relocate. Interested in overseas employment as well. Contact at 5404 Boca Grande Circle, Dover, Fl. 33527. 772-485-2775 RACHEL WOOD – Seeking a Water/Wastewater Trainee position. Has passed tests and needs plant hours to obtain license. Prefers Orange, Seminole, Volusia, or Brevard County. Contact at 298 Hickory Ave,, Oak Hill, Fl. 32759. 386-847-1814
Looking For a Job? The FWPCOA Job Placement Committee Can Help! Contact Joan E. Stokes at 407-293-9465 or fax 407-293-9943 for more information.
Classified Advertising Rates Classified ads are $20 per line for a 60 character line (including spaces and punctuation), $60 minimum. The price includes publication in both the magazine and our Web site. Short positions wanted ads are run one time for no charge and are subject to editing. ads@fwrj.com Florida Water Resources Journal • May 2015
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Certification Boulevard Answer Key From page 30 February 2014
Editorial Calendar January ......Wastewater Treatment February ....Water Supply; Alternative Sources March ........Energy Efficiency; Environmental Stewardship April............Conservation and Reuse May ............Operations and Utilities Management; Florida Water Resources Conference June ..........Biosolids Management and Bioenergy Production July ............Stormwater Management; Emerging Technologies; FWRC Review August........Disinfection; Water Quality September..Emerging Issues; Water Resources Management October ......New Facilities, Expansions, and Upgrades November ..Water Treatment December ..Distribution and Collection Technical articles are usually scheduled several months in advance and are due 60 days before the issue month (for example, January 1 for the March issue). The closing date for display ad and directory card reservations, notices, announcements, upcoming events, and everything else including classified ads, is 30 days before the issue month (for example, September 1 for the October issue). For further information on submittal requirements, guidelines for writers, advertising rates and conditions, and ad dimensions, as well as the most recent notices, announcements, and classified advertisements, go to www.fwrj.com or call 352-241-6006.
Display Advertiser Index Aqua - Aerobic ..................................19 Auto Meg ..........................................54 Blue Planet ........................................61 Brown & Caldwell ..............................13 CEU Challange ..................................48 Conshield/Permaform....................20,46 Crom..................................................50 Data Flow ..........................................45 Evoqua ..............................................41 Florida Aquastore ..............................52 Fluid Control ......................................32 FSAWWA Ace ....................................14 FSAWWA Call For Papers....................34 FSAWWA Confernce ..........................49 FSAWWA Likins..................................24 FWPCOA Region IV ............................47 FWPCOA Training ..............................29 Garney ................................................5 Gemini Group ....................................35 GML Coatings ..............................12,27 Hudson Pumps ..................................33
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Hydro International ............................28 ISA ....................................................15 LFManufacturing................................51 Mathews..............................................9 PC Construction ................................54 PCL....................................................21 Reiss Engineering ..............................40 Stacon ................................................2 Stantec ..............................................16 Treeo ................................................39 USA Blue Book ....................................7 Wade Trim..........................................53 Xylem ................................................62 FWRC PROGRAM ADVERTISER INDEX Atkins ..................................................4 Florida Gateway College ....................19 Hanson ..............................................25 MAXEFF ............................................26 Ovivo ..................................................9 Raven ................................................16
May 2015 • Florida Water Resources Journal
1. D) Increase in volatile acid/alkalinity relationship Because the alkalinity is so high in an anaerobic digester, the pH is slow changing and the digester will basically go “sour” before the pH begins to drop. This is why the acid/alkalinity ratio is the best process tool to use to monitor the performance efficiency of anaerobic digestion.
2. B) Yes, this is acceptable. An acceptable cost of polymer used per dry ton (dt) processed in a BFP depends on the type of sludge and sludge conditioning process. Typically, with anaerobically digested sludge, acceptable polymer consumption is about $25 per dt processed, although more polymer may be used to create higher cake solids. Even with the increased cost for the additional polymer, the overall cost of operation may be reduced due to hauling higher cake solids, less water to haul, and the lower cost per dry ton.
3. D) Temperature These other agents can certainly be harmful to microbiology; however, they are chemical and not physical agents.
4. C) Specific oxygen utilization rate (SOUR) Vector attraction reduction is related to volatile solids reduction, which identifies long-term stability of the conditioned sludge. The SOUR test is the one most used to determine the vector attraction reduction performance of aerobically digested sludge. The maximum SOUR value allowed to meet vector attraction reduction for Class B standards is 1.5 mg/hr/gm total solids, providing that the total solids (TS) content is no more than 2 percent TS.
5. C) The discharge valve must be opened. If a positive displacement pump is started with the discharge valve closed, severe damage can occur within the pump and discharge piping. This can be a very dangerous condition, as pieces of the pump, pipe, or devices on the pipe (like pressure gauges) can become projectiles.
6. B) Chain of custody Chain of custody (CoC) refers to the chronological documentation, or paper trail, showing the seizure, custody, control, transfer, analysis, and disposition of physical or electronic evidence; in this case, samples from a water or wastewater facility.
7. D) 70 to 80 percent Younger sludge will generally have a higher volatile content, while older sludge will have a lower volatile fraction of the mixed liquor total suspended solids.
8. B) Increase the dissolved oxygen (DO) Typically, filamentous microorganisms grow rapidly when the aeration DO is low— maybe between 0.4 to 0.8 parts per million (ppm)—and possibly accompanied with a low F/M ratio. Because filaments are strict aerobes, increasing the aeration DO above 0.8 pp and maybe to about 1.5 ppm, they will NOT decrease the filament growth rate; however, it will increase the healthy floc former growth rate, and the overall ratio of filaments to floc formers will decrease.
9. C) Centrifuge spindown A centrifuge spindown test takes about 15 minutes and provides excellent indication of solids inventory. Comparing spindown test results to laboratory total solids testing can identify increasing or decreasing solids concentration. The centrifuge is not intended to replace a laboratory TS (or TSS) test, but only to supplement the lab data with quick indicators for field process control parameters.
10. B) 1.4 days Step 1: 25 acres divided by 4 zones = 6.25 acres per zone 1 acre = 43,560 ft2 Step 2: 4 in. divided by 12 in. per ft = 0.333 ft of water applied per zone Step 3: 6.25 acres x 43,560 ft2 per acre = 272,250 ft2 x 0.333 ft of water applied per zone = 90,659.25 ft3of water applied per zone Step 4: 90,659.25 ft3 x 7.48 gal per ft3 = 678,131.19 gal of water applied per zone, applying 4 in. of water Step 5: 678,131.19 gal of water per zone divided by 500,000 gal per day flow rate = 1.356 days
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