Table of Contents
INTRODUCTION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
BACKGROUND & ANALYSIS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Goals Findings
IMPLEMENTATION STRATEGIES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Management Principles Operational Goals Campus Recommendations
SELECTED BEST MANAGEMENT PRACTICES. . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 Rain Gardens / Bioretention Underground Storage Stormwater Wetlands Stormwater Terraces
MODEL PROJECTS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 5 Northwestern Academic Quad Cross Creek Environmental Research Park
Lappas + Havener, PA Artifex Environmental Design, Inc.
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The Imperial Building, 215 Morris Street, Durham, NC 27701 3507 Ringsby Court #103, Denver, Colorado 80216
Fayetteville State University
Executive Summary
INTRODUCTION The purpose of the Stormwater Master Plan is to assess how the campus and its infrastructure currently handles stormwater and runoff, and how these processes can be managed in the future to handle stormwater regulations, control costs and maintenance requirements, and improve the campus environment. As buildings and parking areas are added to the campus over time, the quantity of impervious area on campus must be kept within certain limits in accordance with state stormwater and drinking water regulations, and with the City of Fayetteville’s Stormwater Ordinance. In addition, each project will be required to treat both the quality and quantity of runoff leaving the project site to specific established standards. Following rainfall and snow melt events, stormwater runoff is generated when soil and vegetation can no longer completely infiltrate or absorb precipitation. In areas of natural undisturbed conditions, vegetation and soil structure allow a larger fraction of precipitation to be retained, or converted to shallow groundwater. The removal of vegetation, disturbance and compaction of soils, and the introduction of impervious roofs and pavement significantly increases the frequency, volume and rate of runoff compared to predevelopment conditions. Concurrently, a loss of infiltration deprives streams of shallow groundwater recharge that sustains flows during dry weather periods. An increase in the frequency, quantity and rate of runoff, and diminished shallow water recharge, can disrupt the hydrology of streams and rivers, harm estuaries and aquatic ecosystems, and threaten their inhabitants’ survival. These changes in hydrology, combined with urban, agricultural and industrial pollution sources, can lead to the introduction and concentration of water quality pollutants that compound the negative effects on aquatic resources. Uncontrolled and degraded stormwater runoff harms water quality, destabilizes stream banks, and endangers fish populations among other effects, with serious implications for aquatic resources, human health, and statewide, regional and local economies. Recognizing these potential hazards, Federal and State governments have enacted legislation designed to mitigate the effects of surface water discharge and urban development on water quality. In North Carolina, the State Stormwater Program and the 1989 Water Supply Watershed Protection Act implement controls on discharge, development and stormwater runoff quantity and water quality. The local watershed protection ordinance, established in 1993, initiated the City of Fayetteville’s administration and enforcement of the Act’s provision to protect drinking water quality from surface water discharges, including stormwater. Due to special concerns about the aquatic resources, shellfish, and estuaries in eastern North Carolina, the State has introduced nutrient reduction requirements for development in the Neuse and Tar-Pamlico river basins, and for other classified Sensitive Waters. It is expected that similar nutrient reduction requirements will be extended to the Cape Fear basin in the future, thereby affecting the Fayetteville State University (FSU) campus stormwater requirements. Stormwater and pollution control regulations have both management requirements and cost implications for developers and system operators such as FSU. As a State entity, FSU is accustomed to a regulatory environment that is relatively independent of the City of Fayetteville. For most aspects of campus development, FSU has not been subject to local land use or site plan regulations. In the area of State stormwater regulation, however, the City of Fayetteville has been given administrative and enforcement jurisdiction over State and Federal entities within its boundaries. This authority is specifically granted by State statute to the City as the permitting agency that is charged with enforcing Federal and State stormwater regulations within its boundaries. This means that although FSU is not subject to City Site Plan review, FSU is subject to binding review of stormwater control plans by the City.
Stormwater Master Plan
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Executive Summary
The City’s authority to review stormwater plans created by FSU and its contractors means that the University must observe the City’s storm water-related ordinances. The enforcement of these ordinances has implications for both the density of future development and the type of stormwater controls that will be required to be built on campus, and thus could potentially affect the University’s plans for capital improvements as outlined in its Master Plan. For this reason, FSU retained consultants Lappas + Havener PA and ArtifexED to create the University’s first Stormwater Master Plan (SMP). The SMP is comprised of an inventory of existing campus conditions, a survey of regulatory conditions, and recommendations and guidelines for the storage and treatment of stormwater runoff generated on campus, as well as ongoing management of the campus stormwater system and facilities.
BACKGROUND & ANALYSIS Goals The following goals were developed by the consultant team in collaboration with the University’s Facilities Management Department: 1. Ensure that FSU complies with stormwater regulations according to State and local laws. 2. Exceed ordinance-mandated requirements where possible, in order to create a more sustainable campus and to promote flexibility in the event of future changes in stormwater regulations. 3. Integrate stormwater management into campus landscapes in a way that supports the educational and open space goals of the University; this will include sustainable design and interpretive elements. 4. Enable new construction projects on campus to fulfill their requirements while avoiding the siting of large ponds or detrimental landscape features in important campus areas. 5. Provide a framework for ongoing monitoring of campus impervious areas and stormwater resources, and guidance for continuing operation of the stormwater system. Findings The essential findings of the research and analysis phase of the SMP are as follows. Stormwater regulations to which FSU is subject fall into two primary categories: State-mandated watershed protection measures, and mandates related to the National Pollutant Discharge Elimination System, or NPDES. The City of Fayetteville, empowered by the North Carolina Department of Natural Resources, has permit administration and enforcement authority in both categories as they relate to campus operations and development. Watershed Protection Requirements • Watershed protection measures for the FSU campus are related to the campus’s proximity to nearby water resources such as Glendale Lake and Cross Creek. The Watershed Protection Ordinance administers development restrictions for watershed protection areas established by the State. These protection areas overlay portions of the campus and cap 4
Fayetteville State University
Executive Summary
the overall impervious at either 50% or 70% of the overall area, depending on proximity to the water supply intake. These caps, however, pertain only to the net increase in development that has occurred since the enactment of the Ordinance in 1993. The campus impervious surface (development) that predates 1993 does not count toward the cap. For FSU, this means that the campus is unlikely to exceed the caps mandated by the Watershed Protection Ordinance unless the ordinance is changed, or interpreted differently. Because changes in the Ordinance are always a possibility, however, and because each new project will need to demonstrate compliance, it is important that FSU continue to monitor the percentages of impervious surface on various subareas of campus. The data files created by the SMP can form the basis for such an inventory.
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Watershed Boundaries within the study area.
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PRIORITY new development is limited to
70% impervious
CRITICAL 50% impervious
CRITICAL new development is limited to
50% impervious
Water Supply Watershed Boundaries within the study area. Stormwater Master Plan
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Executive Summary
• In the course of researching the City’s interpretation of the Watershed Ordinance, the consultants found that the City considers the FSU campus low density for the purposes of the Ordinance. Thus, the City will not require the same level of stormwater controls for the FSU campus as it would for a site designated as high density. However, if the threshold for low density development is exceeded, retoactive stormwater quality controls will be required under the City permit authority. This finding may be favorable to FSU in terms of development costs for stormwater management. If all development remains at a low density classification, structural water quality BMPs will not be required by the City. • The SMP used Geographic Information Systems (GIS) to measure the amount of impervious surface proposed by the Master Plan. The resulting ratio was compared against the limits imposed by the Watershed Protection Ordinance to verify that, as impervious surface limits are currently interpreted by the City of Fayetteville, the campus is unlikely to exceed the caps mandated by the Ordinance.
Analysis of proposed impervious surface according to the 2008 Campus Master Plan. Existing buildings shown orange, proposed shown red.
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Fayetteville State University
Executive Summary
NPDES Requirements • The second broad category of stormwater controls is based on the Phase II requirements of NPDES. Under the City of Fayetteville Stormwater Ordinance, all non-exempt1 projects are required to detain stormwater to predevelopment discharge rates for the 1-year and 10-year storms. Additional requirements for managing stormwater quality are required for high density and low density projects, with structural BMPs required to manage high density stormwater runoff. It is the planning and management of these facilities that forms the backbone of the Stormwater Master Plan. • The storm drainage infrastructure on campus shows evidence of age related deterioration, insufficient maintenance, and potentially damaging erosion in a number of locations2. Implementation of an inspection and maintenance program to reduce the risk of property damage or injury is one of the key recommendations of this study. The analysis of the trunk storm sewers (those 24” in diameter and larger) indicates that the major existing infrastructure is largely sufficient for existing conditions, but will require major improvements to meet the requirements of the Campus Master Plan.
Campus Storm Drainage and Surface Water Features.
1 The exemptions allowed under the Stormwater Ordinance include a 2,000 sf allowance for redevelopments, and a 20,000 sf allowance for new projects. However, since the City of Fayetteville has indicated it will treat all Campus developments as a single project, these exemptions do not apply on a per project basis. The 2,000 sf exemption was utilized on the Mitchell Building redevelopment in 2011. 2 These locations have been identified in the appendices and photographic records.
Stormwater Master Plan
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Executive Summary
IMPLEMENTATION STRATEGIES Management Principles The proposed stormwater management strategy for new development is focused on the postconstruction treatment of stormwater runoff through the use of distributed controls for peak flow, volume, and water quality treatment. The following strategies provide a suggested framework to meet the University’s stormwater management requirements for new development and provide substantial stormwater management improvements to the existing system as resources are available. 1. Treat net impervious (new impervious construction less existing impervious area) at or near the proposed building, parking or other impervious area, or within the local watershed. This will result in integrated, distributed stormwater features that work at the landscape level, the urbanized design, and are more readily maintained. 2. Treat all constructed impervious areas for peak flow reduction and water quality centrally at stormwater management facilities within the East campus natural area adjacent to Cross Creek. These areas would include new pavement areas that replace existing demolished pavement. The use of larger, more naturalized features will be more economical and compatible with the proposed uses of this area of the campus. Individual small projects that net less than 2,000 square feet of additional impervious would be accounted for in this treatment strategy. 3. Retrofit, restore, and repair existing building or parking drainage and stormwater management where significant opportunities exist. These interventions would be located where significant runoff is generated, erosion and infrastructure damage is observed, or areas with creek and drainage feature instabilities. 4. Document the stormwater treatment deficit for existing and interim projects since the establishment of the 1993 stormwater baseline. This treatment volume would be incorporated in future stormwater retrofit projects, or included in stormwater treatment expansions for proposed facilities as a voluntary measure. 5. Identify areas for local and regional stormwater management within the context of the Campus Master Plan. The locations of these areas will be selected for appropriateness under the master plan and engineering feasibility, and will serve to address holistic stormwater management solutions for the campus and adjacent watersheds. 6. Meet the specific criteria for the type, configuration, and location of stormwater features and Best Management Practices established in this Plan. The proposed features described in this plan have been selected for their compatibility with the site constraints, program requirements, and the concepts introduced in the Campus Master Plan.
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Fayetteville State University
Executive Summary
Operational Objectives In addition to the strategy for stormwater management construction, a series of key recommendations have been developed to improve the accountability and performance of the stormwater infrastructure. These recommendations are targeted at improving the stormwater quality of runoff from the campus, improving the management of the stormwater and related infrastructure, and enabling the University to meet the regulatory stormwater reporting requirements. 1. Develop and maintain a spatial database of the stormwater infrastructure. The database can be based on work products created during the development of this Plan. The implementation may involve the training of staff or the use of outside consultants. The primary purpose would be to allow the facilities division to track issues related to stormwater infrastructure maintenance and operation efficiently and effectively, and to inventory impervious area across the campus. The database will facilitate tracking impervious areas from discrete projects within a single system which will reduce errors and facilitate accurate reporting. The database will serve as a key operational feature for the following inspection and maintenance recommendations. 2. Initiate a program for routine inspection and maintenance of stormwater and related infrastructure. Inspection of the stormwater infrastructure will include simple visual observations and reporting. These observations may lead to simple maintenance, cleaning, and repair activities which will benefit the performance of the stormwater system. More involved or complex maintenance projects may be required; in this case record keeping will facilitate appropriate planning and execution during capital improvement projects. As the University implements further stormwater facility construction, the operation and maintenance requirement of each facility can be incorporated into this program, ensuring that the maintenance responsibilities are adequately met with the proper resources. Training will likely be required to enable each facility’s staff to undertake the additional inspection and maintenance tasks safely and effectively.
Stormwater Master Plan
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Executive Summary
Northwestern Academic Quadrangle The 25-acre area comprising the Northwestern Academic Quad and its surrounding watershed is proposed as a holistically-planned environmental management and campus renewal project. Incorporating stormwater capture, filtration and groundwater reuse strategies capable of treating current and future development planned within the Quad, the design would be fully integrated into the structure of campus green spaces. The proposed Quad redevelopment would be multi-functional - providing a series of rain gardens (bioretention areas) that would store and cleanse stormwater from adjacent building rooftops and parking areas. The project would also introduce new walkways, seating and gathering spaces that collectively would create a vibrant campus amenity.
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Fayetteville State University
Executive Summary
The Quad design will be framed by an upper primary walkway that will connect existing and future academic buildings facing the main open space. Smaller rain gardens would be located between the buildings and the walkway in concert with building entrances. Reclaimed spring water currently captured by a sump in the boiler room of the Lilly Gymnasium building would be utilized as a source for a prominent water feature at the upper plaza level. The focus of the Quad would be a centralized stormwater garden pond and terraced seating space. The stormwater element would be developed in concert with the proposed Quad improvements to provide a unique stormwater demonstration garden that is functional and aesthetically compatible with the character of FSU’s improved social spaces. Stormwater storage devices would recirculate captured stormwater for reuse in campus irrigation systems and pond recharge.
Stormwater Master Plan
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Executive Summary
Cross Creek Environmental Research Park The existing woodland bordering Cross Creek in the southeastern portion of campus presents a unique opportunity for Fayetteville State University to combine physical campus improvements with its environmental sustainability mission. The project would also create a new potential to advance the University’s academic enterprise, especially in the STEM disciplines. Through the implementation of “green” technologies and innovative design, this previously underutilized campus green space is proposed to be transformed into an outdoor learning environment for multiple fields of study as well as a quiet respite for students, faculty and visitors to enjoy. Interspersed with several pockets of natural wetlands, the 25-acre woodland presents a unique environmental asset on the FSU campus and an opportunity to become a multi-purpose education and recreation feature. A series of bioretention terraces, constructed wetlands and vegetated filtration areas would combine to provide stormwater detention and water quality enhancements as part of the campus-wide sustainability strategy. For several decades, the FSU Department of Natural Sciences has conducted plant and animal inventories and field research in this wooded area. The project design would add both aesthetic and environmental diversity to the woodland, and promote its use as an “living laboratory” for a variety of academic observation, study and research endeavors in the biological physical and natural sciences.
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Fayetteville State University
Executive Summary
An overlook plaza would provide a prominent focal element for the Park, allowing views onto the woodland pond, the enhanced wetlands and riparian forest. The terraced observation area would accommodate a range of programmed and impromptu student and visitor gatherings. Trails and walkways through the wooded area would make the natural area more inviting and accessible to campus activity, while leaving large areas of the lowlying woodlands undisturbed for continued academic use. Future connection with the planned municipal greenway network may also be possible.
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