Where Does All that Rain Water Go?
by Kathy Barnard, Marketing and News Services
Where is all of the rain water of the past several weeks ending up, and more importantly to WSU Extension educator Curtis Hinman, how is it getting to its final destination?
How development of once open, plant-covered spaces changes stormwater movement over and through the landscape is one of the greatest threats to water quality, supply and aquatic habitat in the Puget Sound area, according to Hinman, who works at the WSU Pierce County Extension office at Tacoma. One of five Extension faculty working on water issues in the Puget Sound Basin, he researches, designs and monitors low impact development strategies for that region.
"Both resources and attention are turning to stormwater management throughout western Washington," said Hinman. "We have started to realize that even a small amount of urbanization can dramatically affect the watershed."
The major challenge of stormwater management is its complexity, he added. "There are literally thousands - maybe even millions - of individual actions that contribute to the issue."
For example, the transition from meadow to shopping mall increases impervious surfaces such as roads, parking lots, sidewalks, rooftops and compacted soils. Native plants and the upper soil layers that filter, store or allow rainwater to return to the atmosphere are typically removed, creating a "double whammy" with water quality and movement.
"Water quality is impaired as stormwater flowing from impervious surfaces collects oil, grease, heavy metals and other pollutants and is discharged to streams, lakes, wetlands and the Sound," Hinman explained.
Those same surfaces also cause stormwater to move out of a specific landscape more quickly, altering stream channel form and degrading aquatic habitat and the ability of fish, insects and other stream life to survive.
Properly managing stormwater "comes down to good watershed planning, effective design at the project site and to individual residents,"
Hinman said. "It is much more based on the actions of individual property owners; it brings the individual into the ecology of the watershed."
Low impact development can be a solution, he added. It is a land- use development strategy that emphasizes protection and use of features already on a building site as well as small scale, engineered controls on individual lots and at the subdivision level to manage stormwater.
Specific strategies include minimizing building footprints and road widths to reduce impervious surfaces; using permeable paving wherever possible; creating small "bioretention" areas with appropriate soils and plants to filter and store stormwater; and managing stormwater as close to its origin as possible.
More information is available by contacting Hinman at 253/798-3257 or chinman@wsu.edu.
January 6, 2006
WSU Webcasts
Stormwater Management - archives several webcasts:
"Stormwater Management from a Watershed Perspective: Extreme Western Climates" - This is the fifth program in the award-winning Watershed Issues Satellite workshops offered by the Pacific Northwest Regional Water Quality Program. In this program Anchorage, Alaska's Municipal Public Works Department, Anchorage Waterways, and the Alaska Department of Environmental Conservation join with the Pacific Northwest Regional Water Quality Team to demonstrate the strategies used in a northern city to manage contaminant movement from salted and graveled city streets and parking lots snowpiles to the City's numerous salmon bearing creeks.Working with the Coordinator of Arizona's NEMO (Non-point Education for Municipal Officials), the cameras record strategies used to control the massive runoff caused by summer 'monsoon' rains. One of the working strategies for controlling storm water runoff in Arizona is harvesting rainwater fro irrigation. Managing storm event caused sediment erosion is a major problem; we visit with state and local government entities to view their strategies.A panel that includes practitioners from the two areas and an EPA permit writer will be available on camera to answer questions that may be generated by the prescriptions shown. Audience participation is available through telephone, fax, and e-mail in hopes that no question goes unanswered. On the air discussions are invited in the final segment of the programming.
Stormwater Management from a Watershed Perspective - The Pacific Northwest Regional Water Quality Program’s Watershed Issues Series is turning its focus to strategies used by municipalities and homeowners to manage stormwater. The case studies reflect use of Low Impact Development techniques to manage runoff on-site and minimize pollution loading to waterways. Every year, billions of gallons of untreated stormwater flow into streams and rivers across the nation. The Environmental Protection Agency calls it the “number one water quality problem.” To learn how you can be part of the solution, please join us as we explore successful stormwater management strategies used in three watersheds across the nation - Boone, NC, Willoughby, OH and Portland, OR.