WASHINGTON, DC, January 24, 2006 (ENS) - The U.S. Census Bureau projects that U.S. population will grow by 50 million people, or approximately 18 percent, between 2000 and 2020. To deal with the stormwater runoff resulting from this population growth, the U.S. Environmental Protection Agency (EPA) this week released four new smart growth publications:
Protecting Water Resources with Higher-Density Development
Using Smart Growth Techniques as Stormwater Best Management Practices
Growing Toward More Efficient Water Use: Linking Development, Infrastructure, and Drinking Water Policies
Parking Spaces / Community Places: Finding the Balance through Smart Growth Solutions
The study detailed in "Protecting Water Resources with Higher-Density Development" intends to help communities better understand the impacts of higher and lower density on water resources, the agency said in a statement.
The EPA modeled stormwater runoff from three different densities at three scales - one-acre level, lot level, and watershed level - and at three different time series build-outs to examine the premise that lower-density development is always better for water quality.
The findings indicated that "low-density development may not always be the preferred strategy for protecting water resources. Higher densities may better protect water quality - especially at the lot level and watershed scale," the EPA said.
The study found that higher-density scenarios generate less storm water runoff per house at all scales - one acre, lot, and watershed - and time series build-out examples. For the same amount of development, the EPA says, higher-density development produces less runoff and less impervious cover than low-density development.
For a given amount of growth, the agency found, lower-density development impacts more of the watershed.
But this is one of the more controversial areas in water quality. Some stormwater professionals take issue with these findings, saying that increasing density does not protect water resources.
Instead, they advise, the most effective way to protect water quality is to reduce the amount of runoff from a site with the use of measures such as bio-swales, cisterns, porous paving, dry wells, green roofs, and native landscaping.
"Protecting Water Resources with Higher-Density Development" is found at: http://www.epa.gov/smartgrowth/water_density.htm
To comply with the Clean Water Act, over 6,000 communities across the nation are developing municipal stormwater permitting programs, also known as Phases I & II. Many of these communities are also implementing programs that encourage development in existing communities, redevelopment of vacant properties, promote transportation options and facilitate efficient use of land and infrastructure.
"Using Smart Growth Techniques as Stormwater Best Management Practices" reviews nine common smart growth techniques and examines how they can be used to prevent or manage stormwater runoff. The EPA says this publication will help communities encourage smart growth and meet the new regulatory requirements. It is found at: http://www.epa.gov/smartgrowth/stormwater.htm
The publication, "Growing Toward More Efficient Water Use: Linking Development, Infrastructure, and Drinking Water Policies" focuses on the relationship between development patterns, water use, and the cost of water delivery.
It reviews literature that shows how large-lot, dispersed development patterns cost more to serve because of the length of pipe required, pumping costs, and other factors. The literature reviewed shows how large-lot, dispersed development uses more water than smaller lot, higher density development.
This publication concludes with policy options for states, localities, and utilities that directly reduce the cost and demand for water, while indirectly promoting smart growth. These policies offer opportunities for more efficient water use at a time when many communities face water shortages due to drought.
"Using Smart Growth Techniques as Stormwater Best Management Practices" is online at: http://www.epa.gov/smartgrowth/water_efficiency.htm
"Parking Spaces / Community Places: Finding the Balance through Smart Growth Solutions" highlights approaches that balance parking with broader community goals.
Current codes typically apply inflexible minimums that ignore community and developer priorities including environmental quality and human health. An oversupply of unnecessary parking wastes money and creates places that degrade water quality and encourage excess driving and air emissions.
The highlighted solutions cover a range of supply management, demand management, and pricing strategies. Communities have found that combinations of parking pricing, shared parking, demand management, and other techniques have helped them create vibrant places while protecting environmental quality and still providing for necessary vehicle storage.
"Parking Spaces / Community Places" is found at: http://www.epa.gov/smartgrowth/parking.htm
For free hard copies of any of these publications, send an e-mail to ncepimal@one.net or call 1-800-490-9198.ENS
