Rethinking Stormwater in the Concrete Jungle

Rethinking Stormwater in the Concrete Jungle

By Lily Forest, November 2013.

Is your organization’s building or campus part of the stormwater problem or part of the solution? Read on for how to score sustainability points and reduce maintenance costs by actively managing stormwater.

Stormwater management is important in city planning, not only to reduce flooding in cities, but also because of its effect on water bodies we depend on. Large manmade surfaces, like parking lots, highways and sidewalks, make it more difficult for aquifers and other water bodies to be replenished; they also are one of the main sources of pollution for stormwater. Watch this video prepared by the Natural Resources Defense Council to find out how stormwater runoff affects health, city planning, and the economy. Effective management can reduce pollution in the waterways that lead back to rivers, streams, and often, the ocean.

Why should your organization invest in stormwater management?

  1. Meet building code requirements: Many city building codes include stormwater measures.
  2. Avoid hefty fines: National Pollutant Discharge Elimination System (NPDES) is a program under the federal Clean Water Act that regulates stormwater discharges associated with sewer systems, and industrial and construction activities. The US EPA is known to have fined organizations found in non-compliance of the program.
  3. Reduce water costs and other maintenance costs through measures such as rainwater harvesting and green parking lots.
  4. Reduce pollution effects and improve aesthetics with the use of green roofs and vegetated filter strip
  5. Earn LEED and Living Building Challenge Certification: Investing in low-impact development (LID) can help earn certifications that can, ultimately, make an organization more competitive. By writing and implementing a stormwater plan that helps the water system, companies can earn points with LEED. Many other challenges and certifications look for stormwater management, including the Living Building Challenge. Read more about stormwater management and LEED here, plus read through some case studies. Read more about the Living Building Challenge.

How your organization can be part of the solution

Low Impact Development or Green Infrastructure is a broad term that includes many types of practices, but that treats rainwater as a resource by recreating or mimicking natural filtration processes to preserve, move, or contain this water. This type of development also focuses on on-site filtration, storage, evaporation or other mechanisms. Other practices to increase water penetration into the ground includes drought tolerant landscaping, infiltration basins, green roofs, and rain gardens (gardens meant to withstand extremes of moisture and nutrition load, consistent with runoff). Even cemented areas can become systems of movement and penetration into the soil. Curbs, sidewalks, and parking lots can be retrofitted or built to encourage water infiltration. Click here to read more about these LID practices including rainwater harvesting, green parking, permeable pavement, rain gardens and living roofs. Many of the LID or Green Infrastructure practices can have benefits beyond sustainable stormwater management, such as rainwater catchment (also known as rainwater harvesting) which can reduce water bills, green roofs which can reduce energy bills and green parking design which can reduce maintenance costs and pollution effects.

Rainwater harvesting helps reduce stormwater run-off volume by collecting water from dripping roofs, driveways, parking lots and other surfaces. This water can be directly used for landscaping, toilet flushing, and other such needs, which can reduce an organization’s water bills. With filtration, it can also be potable. Use of rainwater depends on laws in a county or a city, but, when permissible, can be captured, used and/or filtrated by households or companies and other organizations. Hey!Tanks LA, a company that recently expanded from Los Angeles up the coast into the Bay Area, bridges the gap between home catchment and larger-scale business catchment, by providing multiple container sizes and a lot of handy information about using greywater and rainwater after it has been obtained. There are other companies as well that offer rain catchment systems, such as RainHarvest SystemsBushman, and Brea’s rainwater catchment systems, which have systems that have helped businesses achieve LEED certification.

stormwater
Permeable pavements allows flat surfaces to become areas of stormwater absorption and movement.
Creative Commons Attribution 3.0 Unported Licenseby Immanuel Giel.
 Green Parking design can significantly reduce impervious surface which helps reduce stormwater volume and also provides a way to filter stormwater to reduce pollution. Green parking design elements also help improve aesthetics. Cities such as NYC have amended their zoning code to require green parking lots which promote better management of stormwater, among other things. Read more to learn more about green parking design in NYC, DC and San Mateo (CA) and for resources on green parking lot best practices. Green Roofs reduce stormwater volume and pollution by creating a natural filter, with the use of plants and vegetation, on the roofs of buildings.

Green roofs have shown to reduce energy costs, create an attractive environment and according the EPA, have lower replacement costs and longer lifecycles than traditional roofs. A well known example is California Academy of Science’s living roof in San Francisco’s Golden Gate Park.

Cities using smart stormwater management

stormwater
A green roof, or living roof, sustains plantlife, while also diverting rainwater and providing insulation to buildings.
Creative Commons Attribution 3.0 Unported Licenseby
Djembayz.

recent paper by the EPA gives some insight into what progressive cities such as Portland, Seattle, San Jose, Philadelphia and eight others have been doing to manage stormwater using green infrastructure. Notably: Philadelphia estimates that its plan will save $8 billion over the life of the program; Seattle has adopted “green” stormwater management approaches which are considered best management practices by the EPA and worldwide. Washington DC’s green infrastructure initiative includes a stormwater credit market where property owners can buy and sell stormwater credits. To learn more about this credit trading program, click here. Although many American cities have implemented forward thinking stormwater management systems, numerous European countries are leading the way in national water management and can be a source of best practices for nationwide change in the US. To learn about Europe’s leading innovator, Germany, read the section on “Transferable Lessons for Green Infrastructure in the United States” about half-way down this page.

Progressive permitting by the California Regional Water Quality Control Boards, which control stormwater regulation and permitting in the state, has encouraged some cities to increase low impact development in construction and re-building. San Jose is one of the cities that has embraced green growth. Any development or reconstruction at or over 10,000 square feet is required to incorporate LID requirements and follow the Urban Management Policy. This policy requires considering runoff early in the permitting process, including how design will filtrate or move water from the building back into the ground or rainwater catchment. The Urban Runoff Management Policy encourages use of landscape as a filter, including use of biofilters and vegetation swales, as well as, including tree planting be included in the filtration process. Another large city in California has adopted an award-winning Stormwater Program by implementing flood control and pollution prevention: Los Angeles. To comply and improve upon state legislation, the City of Los Angeles implemented the Water Quality Compliance Master Plan in 2009; this plan is a 20-year program to clean stormwater and urban runoff before reaching water bodies through green infrastructure. To learn more about Los Angeles’ plan visit their stormwater webpage.

Companies using smart stormwater management

International corporations, such as Johnson & Johnson and Coca Cola, are incorporating low impact development into their building plans. Johnson & Johnson’s corporate campus, which will be finished in 2014, includes porous pavement with an underground infiltration gallery that will capture about 42 percent of stormwater. When the gallery reaches maximum capacity, the stormwater will be filtrated through vegetated swales before reaching stormwater drains. These two management systems, along with any further construction, will filtrate or contain runoff for the entire campus. This campus in Montgomery County, Pennsylvania, will protect the local pond and Neshaminy Creek watershed, as well as buffer the ocean from pollutants and from flooding. To learn more about the Johnson & Johnson Corporate Campus project, click here.

Further Societal Benefits, Health Benefits

Apart from the cost and pollution reduction benefits of managing stormwater, green infrastructure has a benefit for the greater society. Green infrastructure can turn rooftops and beds along streets and highways into lush, blooming areas that can act as water filtration systems, while also sequestering carbon, and adding beauty to an otherwise grey city. This type of infrastructure, that is visibly different, can act as an educational tool at many different levels and inspire organizations and individuals to take action, as in the case of the living roof at the California Academy of Sciences.