Why should Puget Sound residents know the definition of “watershed”?
Because we all live in a watershed, and we all help pollute it.
One solution to the problem is awareness. On Saturday, nearly two dozen people of all ages attended a “watersheducation” class at the WET Science Center in Olympia. Led by AmeriCorps members April Roe and Missy Ayres, the class showed people how to minimize their impact on the health of Puget Sound.
Attendees learned that a watershed is an area of land where water drains into a stream, lake or other body of water. The Puget Sound watershed stretches from Bellingham to south of Olympia.
Water from toilets and sinks goes to a treatment plant, but rainwater flows into storm drains and eventually reaches Puget Sound without treatment. That water is polluted with fertilizers, oil, pesticides, pet waste and anything else it picks up along the way.
Saturday’s class started with a sobering video on watersheds titled “Lost and Puget Sound.” Participants were then challenged to build models of watersheds with paint trays, clay, rocks, moss, sand, soil, sponges and cubes of florist foam. They simulated rain by pouring a full cup of water over each model, which was built on the sloped portion of the paint trays. Any water runoff streamed downhill toward the tray’s basin, which represented Puget Sound.
Some folks collected nearly zero water runoff — meaning their watersheds worked the best.
As the region’s population grows, so does the amount of concrete and asphalt, which prevents the watershed from properly absorbing rainwater. This type of surface — called impervious — represents 60 percent of the land surrounding Puget Sound. As a result, up to 30 percent of runoff ends up in Puget Sound, carrying contaminants with it. In undeveloped watersheds, that amount is around 1 percent.
The impervious surfaces make cities more vulnerable to flooding. Watersheds with more vegetation and loose soil can better absorb and filter water.
A local example of the concept in action can be seen at Yauger Park, which features a wetland created to capture stormwater runoff and prevent flooding on Olympia’s west side. The park’s retention pond is designed to filter contaminants from stormwater, which is released into Percival Creek and Budd Inlet.
Thurston County is home to smaller watersheds within the larger Puget Sound system, including the Budd Inlet watershed.
Andy Hobbs: 360-704-6869