Green Storm Infrastructure in Los Angeles: Priority sites + implementation strategies
Megan Echols | Andres David Quinche | Laurel Schwab Water Resource Development & Management Harvard Kennedy School of Government
Image Source: Carolyn Drake
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
Image Source: Metropolis Magazine
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
table of contents PART I (Background) 1. Introduction 2. The Los Angeles Water Basin 3. Policy Makers + Stakeholders - Public Agencies - Community Agencies 4. Existing Policies + Regulations 5. Precedents 6. Policy Questions PART II (Analysis) 7. Methodology 8. Data + Mapping 9. Results + Recommendations 10. Conclusion
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
1. Introduction Los Angeles, California, is a rapidly growing city of 3.8 million in the arid climate of Southern California. As a result of natural resource constraints, misguided policy and engineering decisions of the past century, and difficult weather patterns in recent years, the city is confronting a number of water resource-related challenges simultaneously. As a recent New York Times opinion piece declared, “The water-supply infrastructure imported water while the floodcontrol system exported it, and both processes ravaged the environment.” 1 The City of LA’s water management policy is also embedded in a complicated landscape of regional, county, and state agencies all working towards achieving various water quality and quantity goals. Recently, the city has turned towards a new method for addressing issues related to both quality and quantity of the water it uses and consumes: green stormwater infrastructure (GSI). What follows is a brief context surrounding the issues, an analysis of the city’s current water management strategy, and recommendations for how the city can use GSI to have the greatest positive impact on its water resource problems and its residents. Our analysis will focus on ways in which greenblue infrastructures and design driven approaches can play a large role in the adaptation, greening, and water harvesting of the LA Metropolitan Region. Green stormwater infrastructures are defined by the Environmental Protection Agency as water management measures that treat stormwater at its source while delivering environmental, social, 1
“LA: City of Water”
and economic benefits. 2 Typical stormwater management strategies aim to move water off-site and into storm drains as quickly as possibly; they typically are very costly and have proven to overburden waterways with runoff pollution. Low Impact Development (LID) and GSI aim to do the complete opposite. These strategies aim to keep more water on-site for a longer time in order to let it absorb and infiltrate. They also aim to control urban runoff and pollution right at the source. These softer infrastructures emphasize more localized approaches and decentralized solutions that capitalize on the beneficial services that natural ecosystem functions can provide. Los Angeles Metropolitan Region is nearing half a decade of drought and it has recently reached the highest drought levels ever recorded in its history. Since July of 2015 roughly 58% of California has experienced “exceptional” drought, the worst out of the fivelevel scale. 3 Experts say that Los Angeles has not experienced this level of drought since the 1920’s and 70’s. 4 In the long term, the most recent science predicts that overall the Los Angeles region will tend to see the same average amount of precipitation during the next century, but that due to climate change more of it will fall as rain rather than snow and will come in fewer but more severe rainfall events. 5 The southern California region depends heavily on seasonal snowpack for continued water supply into the summer months, so 2 https://www.epa.gov/green-infrastructure/ what-green-infrastructure 3 http://droughtmonitor.unl.edu/ 4 LA Times 5 UCLA Study
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
this shift makes it even more crucial for LA to capture water as it falls and increase their local supply. Another issue is Los Angeles’ overwhelming reliance on imported water. The Los Angeles Department for Water and Power (LADWP) estimates that 85% of the city’s water demand is met by sources hundreds of miles away, coming to LA from the Bay Delta and the Colorado River. 6 With increasing environmental and legal pressures on these far-away sources, it is crucial that LA meet more of its water demand with local water. The water management challenge in California stems from the yearto-year variability in available surface water given the hydrologic conditions from the wet and dry years. Additionally, multiple environmental regulations may result in temporary or permanent restrictions on certain water supplies for the LA Metro Region. 7 That is not to say that there doesn’t exist tremendous opportunity for capturing and re-using water. The LADWP estimates that an additional 68,000 to 114,000 acrefeet per year could be realistically captured through a suite of projects, programs, and policies over the next 20 years, for a total of up to 180,000 acre-feet captured annually. 8 A more aggressive estimate suggests as much as 253,000 acre-feet per year could be captured by the year 2099. 9 There are a large number of agencies involved in water quantity 6 LADWP Stormwater Capture Master Plan, pg ES-2 7 LADWP Water Management Plan, Pg. 31 8 LADWP Stormwater Capture Master Plan, pg ES-1 9 NRDC.ORG
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and quality management, and they all have various master plans and initiatives launched within the last decade or generated by requirement every few years. Some of them have been created in coordination with other existing programs, but a greater degree of coordination would heighten the efficacy of their stormwater capture strategies. One key turning point was very recent, when LADWP released their Stormwater Capture Master Plan in December 2015. The document, described in more detail later, is the first step towards a more cohesive program for improving water quality and securing more local water supply through the use of green stormwater infrastructure. The strategy is divided into centralized and distributed capture projects; LADWP has made preliminary calculations as to how many aggregate acre-feet of water could be captured through both mechanisms. One of the plan’s implementation recommendations is to identify more clearly the locations of both types of projects throughout the city and establish a hierarchy of locations most in need of stormwater projects: “To achieve the implementation rates proposed in this document, a systematic approach for identifying specific subregional and green street project opportunities should be developed so that distributed projects can be implemented more programmatically, rather than as individual projects.” 10
10 LADWP Stormwater Capture Master Pla, pg 80-81
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
2. The Los Angeles Water Basin The analysis that follows suggests priority locations for investment in GSI, according to three criteria: 1. Areas with most capability to recharge local groundwater supply Because of Los Angeles’ extreme reliance on imported water, this criterion was selected in order for GSI investments to provide effective increases in the city’s local water supply. 2. Areas that already have a focus of compatible planning activity In order to “kill two birds with one stone,” GSI should be incorporated in tandem with ongoing planning and investment activities. As an example, we chose to focus on the ongoing Transit Oriented Development initiative being developed by the LA County Regional Planning Commission. TOD areas are highly compatible with GSI because of their intention of reducing parking and creating an enjoyable pedestrian atmosphere. 3. Areas that are highly burdened with low income, minority populations and that lack quality open space The implementation of GSI produces manifold benefits beyond stormwater capture, including new recreational open space, local air quality benefits, and increased property values. For these reasons it makes sense for Los Angeles to focus its investments in underserved communities, so that this program can be as equitable as possible.
Los Angeles County has four primary watersheds; Los Angeles River, Ballona Creek, Santa Monica Bay (North and South) and the Dominguez Channel. The Ballona Creek Watershed 1 The Ballona Creek watershed covers approximately 130 square miles in the coastal plain of the Los Angeles Basin. The watershed includes the cities of Beverly Hills, West Hollywood, portions of the cities of Los Angeles, Culver City, Inglewood and Santa Monica. The watershed is highly developed: residential (59%), vacant/open space (17%), and commercial (14%). According to the Los Angeles Stormwater Program 49% of the watershed is covered by roads, rooftops, and other impervious surfaces. The Ballona Creek and selected tributaries are highly impaired by pollutants (i.e. trash, metals, bacteria, nutrients) due to the dense population and the large amount of impervious ground surface that prevents large quantities of runoff from infiltrating into the soils. The LA Stormwater program has been diligently working on a Watershed Management Program to clean up the creek and meet the water quality mandates set by the state and federal government. The Los Angeles River Watershed 2 The 55-mile long Los Angeles River originates in the San Fernando Valley and flows south into the San Pedro Bay near Long Beach. 1 http://www.lastormwater.org/about-us/ about-watersheds/ballona-creek/ 2 http://www.lastormwater.org/about-us/ about-watersheds/los-angeles-river/
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
The LA River Watershed covers approximately 834 square miles. The southern portion of the Watershed captures runoff from urbanized areas around downtown LA. The Watershed has multiple jurisdictions, including; The City of Los Angeles (33%); 42 other cities (29%), and eight agencies (37%). Much of the Watershed is developed and it’s land uses are: residential (36%), open space and agricultural (44%), and commercial/ industrial/transportation (20%), one-third is impervious. Much like the Ballona Creek, the LA River Watershed, is highly polluted due to the dense population along its borders and the amount of impervious ground surface that prevents large quantities of runoff from infiltrating into the soils. Pollutants include trash, metals, bacteria, and nutrients. The Los Angeles River had little or no natural flow from June to October; essentially it is considered a “dry river”, with flow occurring in the rainy season from November to May. Over its history the LA river was encroached upon by construction on the floodplain. Inevitable damage from floods occurred in 1914, 1934, and 1938, which prompted the U.S. Army Corps of Engineers to construct the concrete-lined channel that now conveys the river for a majority of its 55 mile course. Dominguez Channel 3 The Dominguez Channel Watershed covers approximately 70,000 acres of land and it is located in the southern portion of the Los Angeles Basin. Parts of Los Angeles 3 http://www.lastormwater.org/about-us/ about-watersheds/dominguez-channel/
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County and over 15 cities and other jurisdictions are located in the Dominguez Watershed. The City of Los Angeles comprises 21% of the Watershed’s area. Over 90% of the land along the Watershed is developed. Residential uses cover almost half of the Watershed (41%), industrial, commercial, and transportation related land uses cover (44%). Impervious surface dominates the Watershed, despite some small, natural creeks and streams.
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
2. The Los Angeles Water Basin
Anteloper + freemont
SANTA CLARA
LOS ANGELES
SAN GABRIEL SANTA monica
Source: GIS + LA GIS Data Portal
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
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3. POLICY MAKERS + STAKEHOLDERS Responsible Public Agencies: The Los Angeles Metro lies within a very complex multijurisdictional region, therefore the implementation of any project or effective initiative to deal with stormwater in the numerous water basins involves a collaborative effort among multiple agencies and city stakeholders. Below is a list of the key institutional agencies and their work related to the water management of the LA Metropolitan Region. State Water Resources Control Board: The SWRCB is a state board responsible for regulating wastewater discharges to both surface water and groundwater. It also regulates stormwater discharges from construction, industrial, and municipal activities; discharges from irrigated agriculture; dredge and fill activities; the alteration of any federally regulated water body; and several other activities with practices that could degrade water quality. The Board gives MS4 (municipal separate storm sewer system) permits to all counties and municipalities in the state. Last June, the SWRCB approved an updated Water Action Plan for Los Angeles County. Among other items, it puts in place new regulations for stormwater capture and reuse. It was heralded internally as a potential model for the rest of the state, but it has been criticized for preserving loopholes and a lack of followup to verify that municipalities are implementing the stormwater management plans they come up with.
Los Angeles Department of Water and Power: The LADWP is responsible for providing the City of Los Angeles with a safe and reliable water supply for residential, commercial, governmental, institutional, and industrial usages. It is the largest municipal utility in the country. The LADWP has been developing a set of multi-pronged strategies and initiatives for stormwater capture, water conservation, water recycling, and groundwater remediation. According to LADWP, on average, more than 27,000 acre-feet (around 8.8 million gallons) of stormwater is captured annually at centralized spreading grounds where it recharges the San Fernando Groundwater Basin. However, the stormwater runoff that cannot be contained at these facilities is discharged to the Pacific Ocean, a significant loss to the drought-stricken region. Given the above, LADWP has embarked on an aggressive water conservation strategy. It has already employed multiple approaches such as investments in state-of-the-art technologies, rebates and incentives promoting installation of weather-based irrigation controllers, efficient household appliances, enforcement of prohibited water uses, and educational and outreach efforts. 1 The Watershed Management Group (part of LADWP) In 2008 the LADWP created the Watershed Management Group, whose responsibility has been to develop and manage the water system’s involvement in emerging 1
LA DWP Water Management Plan, Pg. 40
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
issues associated with local and regional stormwater capture. This group has also been responsible for coordinating activities within other agencies, departments, stakeholders and community groups for the purpose of planning and developing projects and initiatives to improve stormwater management within the city. Metropolitan Water District of Southern California (MWD): MWD is a regional water wholesaler that delivers water to 26 member public agencies, serving 19 million people in Los Angeles, Riverside, Orange, San Bernardino, San Diego and Ventura Counties. They own and operate, among others, the Colorado River Aqueduct. Los Angeles County Flood Control District (LACFCD): Created after a disastrous flood in 1915, the LACFCD provides flood protection, water conservation, recreation and aesthetic enhancement within its boundaries. Within the entity, the Watershed Management Division carries out planning and policy. Established in 2000, the division carries out multi-purpose projects that address the flood risk management, water quality, water conservation, open space, and recreational needs in the District. 2 US Army Corps of Engineers: The USACE is heavily involved in many aspects of water resources management throughout the country. The Corps was involved with the channelization of the Los Angeles River in the 1930s 2 http://dpw.lacounty.gov/wmd/dspAboutUs. cfm
following a disastrous flood. Los Angeles Stormwater Program: The Stormwater Program was created in 1990 in order to improve raise awareness about stormwater pollution and its impacts on the area’s water bodies and beaches. This program’s mission is broadly to protect beneficial uses of receiving waters. It focuses on both flood control and pollution abatement, and ensures Los Angeles’ compliance with federal, state and local regulations. Key activities include water quality monitoring, education, outreach, enforcement, and evaluation of water quality in all four local watersheds. Department of Public Works: DPW houses the Bureaus of Engineering, Sanitation, Street Lighting, Street Services, and Contract Administration. Los Angeles Bureau of Sanitation (LASAN): LASAN is responsible for the planning and operation of the wastewater program. It is also the MS4 (municipal separate storm sewer system) Permit holder charged with the responsibility of complying with the permit provisions. They are also responsible for creating the Enhanced Watershed Management Plans, one for each watershed within LA’s municipal boundary. Responsible Community Agencies: Numerous non-profit groups and community groups have been engaged with the public agencies mentioned above. These groups have worked tirelessly to raise
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
public awareness and encourage civic engagement for the numerous initiatives related to water management and restoration within the metropolitan region. Some of these groups include: Natural Resources Defense Council, Friends of the Los Angeles River, Tree People, North East Trees, the River for Public Land, amongst others.
4.Existin g Policies + regulations The following section will go over the numerous policies and initiatives in the LA region to deal with drought and stormwater management. Low Impact Development Ordinance: The City passed the LID Ordinance in order to require LID principles be integrated into new construction and redevelopment projects throughout LA. There is a guidebook for practitioners explaining how to implement LID principles. The LID ordinance requires rainwater from a three-quarter inch rainstorm to be captured, infiltrated, and used onsite at most developments and redevelopments where more than 500 square feet of surface is added. Most single family residences can comply in a more simple way by installing adequate BMPs such as rain barrels, permeable pavement, rainwater storage tanks, or infiltration swales
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to contain the water. 1 According to the ordinance different types of projects would be subjected to fees and regulations according to the size of surface area being built or modified. Smaller residential projects would have to include one or two of the LID practices into their design plans. Fees for projects involved in 500 square feet of land or more would incur fees between $20 and $200. LA Urban Water Management Plan: The state requires every urban water supplier to produce a plan every five years. It is the primary water supply planning document for every city and town in California. The purpose is to forecast future water demands and water supplies under average and dry year conditions, identify future water supply projects such as recycled water, provide a summary of water conservation best management practices (BMPs), and provide a single and multi-dry year management strategy. 2 The 2015 plan is still in draft form, with final submittal to the state in June 2016. Recycled Water Master Planning Documents: Under the umbrella of the Urban Water Management Plan (UWMP). Launched in 2009 and completed in 2012. These documents were developed by LADWP, BOS, and the Bureau of Engineering (BOE). The major goals are to offset potable 1 http://www.planningreport.com/2012/05/31/ new-low-impact-development-ordinancepromoted-sanitation-s-adel-hagehkalil 2 Water.ca.gov
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
water demand by replenishing groundwater basins with potable recycled water and to expand the non-potable reuse (NPR) “purple pipeline” network to as many LADWP customers as is feasible. All projects implemented under this planning process would be funded by LADWP’s budget. Enhanced Watershed Management Plans: These plans are carried out under the purview of the Bureau of Sanitation. The goal of the Enhanced Watershed Management Plans is to develop plans that provide both water quality and water supply solutions and to treat all water as one water source. This begins to break down the silos of water quantity and water quality. The EWMPs will identify current and future multi-benefit projects that will improve water quality, promote water conservation, enhance recreational opportunities, manage flood risk, improve local aesthetics, and support public education opportunities in each of the five watersheds. These plans are encouraged to be carried out by all MS4 permit holders, but it is not required or enforced. Stormwater Capture Master Plan: This new plan, unveiled in 2015 by LADWP, outlines the city’s strategies to implement stormwater projects over the next 20 years. The Plan aims to reduce the city’s fresh water use by 20% and achieve a 50% reduction in LADWP’s purchase of imported potable water by 2024. Additionally one of the City’s key goals is to increase the local water supply and decrease the
need to purchase imported water. 3 Identified partners are the MWD, LACFCD, BOS, and TreePeople. The plan was developed in close coordination with the Enhanced Watershed Management Plans. A number of different program types with potential projects were identified within the plan, including: - On-Site Infiltration through the Residential Rain Garden Program - Green Streets through the Commercial Green Street Program - Subregional Infiltration through Neighborhood Recharge Facility Program - On-site Direct Use through the Residential or Commercial Cistern Program - Subregional Direct Use through the Park Subsurface Storage and Irrigation Program - Impervious Replacement through the Impervious Surface Replacement Program A detailed analysis was performed on these programs to determine their costs and potential benefits, including capture volume, pollutant reduction, increased green space, and peak flow reduction. The strategy is divided into centralized and distributed capture projects. A crucial next step is to identify more clearly the best locations for both types of projects throughout the city. Water Quality Compliance Master Plan: Adopted in 2009, this is a 20year strategy to reduce urban runoff pollution from stormwater flowing into rivers, creeks, 3 Stormwater Capture Master Plan, LADWP, pg. 17
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
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Low-Impact Development Ordinance
lakes, and beaches. It seeks to create a watershed-based perspective on the issue, offering green infrastructure solutions and methods for cross-agency collaboration. It was developed by the Bureau of Sanitation, Watershed Protection Division, in response to a City Council motion passed in 2007.
other municipalities involved. Lastly as part of this plan, there have been large initiatives to engage the public through arts and culture. Recently the Bloomberg Foundation awarded the city of LA a grant to host the first Art Biennial along the river banks. 4
LA River Revitalization Master Plan: Since its adoption in 2007 the Master Plan has received several funding from multiple cities along its banks and several projects have been implemented, including habitat restoration, parks, and bikeways. Federal funds were also awarded to the project under the America’s Great Outdoors initiative to revitalize the urban waterway and its surroundings. The US Army Corps of Engineers has also recently completed an extensive review, in it acknowledging the federal government’s responsibility to collaborate and support the objective of the city of LA and the
4 http://la.curbed.com/2015/6/23/9947162/lariver-public-art-biennial
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
WATER MANAGEMENT LAWS, AGENCIES, AND GUIDING PLAN FEDERAL
STATE
REGION
US ARMY CORPS OF ENGINEERS
STATE WATER RESOURCES CONTROL BOA
CA WATER CONSERVATION ACT
Requires local water utility to reduce per capita use 20% by 2020
METROPOLITAN WATER DISTRICT
COUNTY
CITY
S t w
LA COUNTY FLOOD CONTROL DISTRICT
State requires local water supply plan every five years
LA DEPT OF WATER & POWER
URBAN WATER MANAGEMENT PLAN
STORMWATER CAPTURE MASTER PLAN
SCMP was coordination wit
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
NS
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PUBLIC AGENCY
LAW/ORDINANCE
MASTER PLANS/ PROGRAMS
ARD
SWRCB issues MS4 permits to LASAN, which is tasked with compliance
LOW IMPACT DEVELOPMENT ORDINANCE LA STORMWATER PROGRAM
LID requirements are included in SCMP calculation PROPOSITION O DEPT OF PUBLIC WORKS
Stormwater program tests water quality and educates the public BUREAU OF SANITATION
WATER QUALITY COMPLIANCE MASTER PLAN
Allows city to fund pollution prevention projects, carried out by DPW
BUREAU OF STREETS
ENHANCED WATERSHED MASTER PLANS
s written in th EWMPs
Source: Authors
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
5.Precedents Philadelphia, Pennsylvania Five years ago, Philadelphia launched the Green City, Clean Waters (CGCW) initiative, a 25year plan to fulfill federal law requirement under the Clean Water Act (CWA). The CWA has required nearly 800 communities nationwide to reduce sewage run-off. Philadelphia’s approach was to strike an agreement with the EPA to pursue a more affordable approach to wastewater management. A $1.6 billion green infrastructure initiative was settled, and since then, over 107 public projects and 389 private projects have been completed. This has translated into around $35 million in total annual revenues for the numerous firms involved and annual economic impacts of $57 million dollars. CGCW continues to provide opportunities for smaller local firms and local employees. The projects are smaller in scale, there are more of them, and they continue for years. Conversely, after a giant holding tank is built, the work is done. Additionally, Philadelphia is also charging higher storm-water fees to properties that generate the most runoff, and reducing fees on lower-impact properties, like high-rise buildings with little surface parking. All of the nonresidential properties in the city, and residential condos over a certain size, pay for the impervious surface with a storm-water fee. A fee of about thirteen dollars is imposed on residential row-homes. Previously, large malls with big parking lots had much smaller fees. Now, these malls are paying huge fees based on the size and impact of these huge parking lots. Additionally, projects over a certain size have to pay for impervious surfaces. This approach is helping
fund numerous projects throughout the city. Copenhagen, Denmark During the summer of 2011, the city of Copenhagen, Denmark, received over 150 mm of rain (over 5 inches) in less than three hours. This resulted in massive flooding throughout the city and damages of almost over one billion USD. This event highlighted the necessity for a more integrated and sustainable urban plan to deal with water. Following the storm, the city published a Comprehensive Climate Adaptations Plan, which focuses heavily on the incorporation of LID and blue-green infrastructures as an integrated part of urban development. The plan considers water as valuable asset to embrace rather than immediately reject. Now Copenhagen uses a holistic and integrated approach to water management. For example, it requires the implementation of wastewater and storm-water management at early stages within any urban planning process. Denmark is also a leader in design driven solutions. It has implemented innovative projects such as the Rabalder a 40,000 square meter skate park that also functions as a site to harvest rainwater. The construction of the park doubles as recreational and storm-water management basin in the city. Another city in Denmark, Kokkedal, is designing a park along its river to slow water flows, allow groundwater to recharge, and remove pollutants. The city recognized that flood storage will be used infrequently, therefore channels and storage areas are made into connecting paths, recreation fields, and attractive social and educational spaces.
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
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6. Policy Questions 1. What criteria should be used to ensure that the implementation of green stormwater projects are first placed in geographic locations that will serve the greatest public good? 2. How should the LA region begin to streamline stormwater management policy in order to quickly achieve water quality and quantity goals?
7.Method ology Our analysis was done primarily through the use of Geographic Information System (GIS) data from Los Angeles County of the four principal watersheds within the Los Angeles Metropolitan Region to assess the impervious cover and locate the best sites for greening and harvesting according to three established criteria: 1. Locations above a groundwater basin that can be recharged that are not burdened by man-made obstructions or heavy pollution due to industrial land use 2. Designated transit-oriented development (TOD) zones, which will need less acreage for parking 3. Underserved neighborhoods, defined here as low-income, highminority areas with a lack of quality open space Once the best sites were identified, a calculation was done in order to serve as a proxy for the amount of impervious surface located within each criteria. To do this we calculated the acres of schoolyards and surface parking lots using the
“Calculate Geometry� function in ArcGIS. The GIS data we used included: - Groundwater aquifers - Major surface water bodies - Land use - Major impervious land uses: schoolyards, parking lots, building footprints, streets - Census data from the 2013 - American Community Survey: median household income, race. - Data was at the census tract level - TOD zones recently designated by the LA County Regional Planning Commission - Open space (regional parks and gardens) Other methods included: - Analysis of 2015 LA Stormwater Capture Master Plan - Examination of other comprehensive stormwater policies (precedents)
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
8. dATA ANALYSIS + MAPPING Identifying Efficient Groundwater Recharge Zones This map was generated by selecting all Class A aquifers as defined by LADWP and eliminating areas that overlap with heavy industrial land use and superfund sites.
Source: GIS + LA GIS Data Portal
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
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TOD Zones and Impervious Surfaces This map was generated with the LA County Regional Planning Commission’s TOD zone data layer. Surface parking lot data was used to serve as a proxy for the depaving opportunities in these zones.
Source: GIS + LA GIS Data Portal
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
African American Population
Hispanic Population
Source: GIS + US Census 2013
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
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Los Angeles Income
Open and Recreational Spaces
These maps were generated with 2013 Census data at the census tract level. The quantitative categories were manipulated to more clearly show census tracts with more than 50% minority population and census tracts with median household incomes of less than $33,000, which is approximately 60% of LA area median income (AMI). These thresholds were our definition of “underserved.�
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
This map was generated by combining layers from the race and income maps to identify census tracts that have both greater than 50% minority population and median income of less than 60% AMI. The open space GIS data layer was also added to show the relationship of these burdened census tracts to existing parks and gardens.
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
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9. Recommendations Efficient Groundwater Recharge Zones Currently, an average of 831,400 acre-feet of water enters Los Angeles as precipitation, runoff, or irrigation. Of that amount, only 92,000 acre-feet or 11% goes into recharge aquifers. Of that amount, 29,000 af enter centralized facilities and 63,000 is considered incidental distributed capture. However, 28,000 af of that incidental capture is essentially trapped above confined aquifers, thus not contributing to LA’s water supply needs. LA can more effectively use green stormwater infrastructure to capture potential supply by prioritizing zones that are most amenable to groundwater recharge, due to the presence of permeable soil types, unconfined aquifers, and no obstacles or extreme pollution nearby. We calculated that within our defined areas (see map), there are 2,184 acres of schoolyard property and 3,235 acres of surface parking. TOD Zones The LA County Department of Regional Planning has begun to identify specific transit-oriented development zones in coordination with their 2035 General Plan, adopted in October 2015. Transit Oriented Districts (TODs) are areas that encourage infill development, pedestrian-friendly and communityserving uses near transit stops. The goal is to encourage walking, bicycling, and transit use. The General Plan adds new TODs and expands existing TODs from approximately a quarter-mile radius to a half-mile radius from the selected transit stations. 1 There are currently 9 designated 1 http://planning.lacounty.gov/tod
zones, but the number could grow in the future; in LA there are 97 transit stops alone, not including bus hubs. TOD zones are a logical place to incorporate green infrastructure because of their potential to remove surface parking, incorporate green streets design elements, and new physical development that can emphasize permeable surfaces, green roofs, etc. We calculated that within currently designated TOD areas (see map), there are 3 acres of schoolyard property and 727 acres of surface parking. Underserved Neighborhoods A geographic analysis of census data pertaining to race, ethnicity, and income revealed a number of specific census tracts that are concentrations of poverty and minorities. With the use of GIS software, census tracts were first identified which have a median household income (MHI) of 60% or less of the Area Median Income (AMI) for the city of Los Angeles, which is approximately $62,000. 2 Selecting only census tracts with MHIs less than 60% AMI revealed all areas where the MHI is less than approximately $37,200. As for analysis of race and ethnicity geographies, Los Angeles is a very diverse city with a particularly large Latino population. Given the relatively high proportion of minorities in most parts of the city, a threshold of at least 50% minority was chosen. Census tract data was analyzed for both blacks and Latinos as self-identified in the 2013 American Community Survey. These revealed two distinct patterns. Northern and Eastern 2 http://www.hcd.ca.gov/housing-policydevelopment/housing-resource-center/reports/ state/inc2k14.pdf
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
Los Angeles both have high concentrations of neighborhoods where more than 50% of the population is Latino, and South Los Angeles has a high concentration of neighborhoods where more than 50% of the population is black. These two demographic traits were combined with the low-income data to reveal highly burdened census tracts. Another geographic overlay employed was the location of parks, gardens, and nature reservations. Unsurprisingly, these burdened areas also have very little open space. These tracts were then located within neighborhoods so as to be more identifiable as locations the city should explicitly target for green infrastructure investment. These areas represent huge potential for distributed stormwater infrastructure projects; for example, there are 826 acres of schoolyard property and 1,977 acres of surface parking lots within these census tracts. Streamlining Implementation In order for Los Angeles to quickly scale-up their green stormwater capture infrastructure, greater coordination and streamlining is required. As seen on pages 1415, a large number of agencies at different geographic scales are working to improve water quality and quantity issues throughout the greater LA region. Now that LADWP has begun a comprehensive stormwater capture planning process, this seems to be the best vehicle to move action forward. One major step will be to convene all of the aforementioned multiscalar agencies in one steering body in order to achieve scale-up at a regional level. In particular, coordination between LADWP, other municipal water utilities
in the area, and watershed management bodies should be formalized. This will enable the entire region to work in parallel; for example, if Los Angeles creates incentives for GSI on commercial properties, it will be far less impactful if the city is working in isolation and other cities within their watersheds are not also taking the same measures. There is some encouragement of regionality embedded in the state’s MS4 permits given to each municipality, but it could be much stronger. The current MS4 permit allows (but does not actually require) permittees to develop Watershed Management Programs and Enhanced Watershed Management Programs, which all of LA’s watersheds have done. 3 The EWMP process is meant to enable permittees to collaborate within their watersheds in order to implement coordinated projects. However, it should be required that permittees engage in this regional planning process and compliance mechanisms should be put in place. Why Depave? The excess of impervious surfaces, which are mainly artificial structures—such as pavements (roads, sidewalks, driveways and parking lots) that are covered by impenetrable materials such as asphalt, concrete, brick, and stone can become problematic for cities. These impervious surfaces may create conditions that adversely impact the ecological systems of their host environments. For example, the coloration and composition of asphalt tends to trap heat during warm days and emits this heat during the night, raising temperatures in the 3
SCMP Appendix F, pg 27
Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
surrounding locale. This effect is typically known as the “heat-island effect”, it can impact human and natural environments, causing buildings’ cooling systems to work more and therefore increasing utility use and cost, while also disturbing the lifecycles of both plants and animals in the area. Urban heat islands, are also detrimental to human health, they contribute to general discomforts, respiratory difficulties, heat cramps, and exhaustion, non-fatal heat stroke, and heat-related mortalities. 4 Additionally, such excessive heat events and dramatic temperature increases, are particularly dangerous. According to research conducted by the Centers for Disease Control and Prevention, between 1979 and 2003 excessive heat exposure contributed to more than 8,000 premature deaths in the United States. 5 This figure exceeds the number of mortalities resulting from hurricanes, lightning, tornadoes, floods, and earthquakes combined. Most pertinent to the Los Angeles case is the impaired water quality caused by impervious surfaces. Surfaces such as parking lots increase runoff as well as sediment and pollution deposits in the bodies of water into which the storm and sewer system drain. The increased water temperature the runs off affects all aspects of aquatic life, especially the metabolism and reproduction of many aquatic species, these rapid temperature changes in aquatic ecosystems may be particular stressful, and even 4 https://www.epa.gov/heat-islands/heatisland-impacts 5 h t t p : / / w w w. b t . c d c . g o v / d i s a s t e r s / extremeheat/heat_guide.asp
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fatal to aquatic life. 6 Given the numerous negative effects of excessive impervious structures, finding ways to depave, could be extremely beneficial, not only for Los Angeles ecosystem and environment, but also for the improvement of the city’s public realm and urban aesthetic. 6 https://www.epa.gov/heat-islands/heatisland-impacts#3
10.Conclusion Los Angeles will continue to face tremendous water challenges in the coming future, as precipitation will become less frequent, yet fewer storms will be more severe, making it more crucial for LA to capture water as it falls and increase their local supply. Despite the extensive planning and the numerous agencies working towards lowering dependency on imported water, replenishing aquifers, and cleaning the waterways more integration and better streamlining will be fundamental for the success of the plethora of water strategies. Our spatial analysis found that the city of LA can take a multipronged approach to dealing with the issues discussed on this paper. Our recommendations follow that the city should focus its GSI’s strategies around; 1) areas of efficient groundwater recharge; 2) depaving around TOD sites; and 3) greening lower-income and underserved neighborhoods. By doing so the city can not only begin to meet its water challenges, but it can also create multiple benefits for the environment and its communities.
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Green Storm Infrastructure in Los Angeles: Priority Sites and Implementation Strategies
Green Storm Infrastructure in Los Angeles: Priority sites + implementation strategies
Report prepared by: Megan Echols | Andres David Quinche | Laurel Schwab Water Resource Development & Management Harvard Kennedy School of Government