Science & Innovations

What is the science behind our work?

The Water Cycle:

Water moves from the air to land and to sea and back again in a hydrologic cycle. Clouds produce rain that returns water to the earth. This water is stored on mountain tops as snow, stored in the earth as groundwater, or flows over the land in streams and rivers into the ocean. Sunlight heats the water on the land or ocean to become vapor which rises to form clouds. The same amount of water is always on the earth, it's just temporarily stored and released in cycle in different ways.

Salmon and Stream Ecology:

The health of a stream and the lifecycle of salmon (and trout) are linked such that both depend on each other. A healthy stream needs healthy fish and healthy fish need healthy streams. Salmon bring nutrients from the ocean back to the land when they spawn and die, leaving their bodies in the stream to decompose. The nutrients are used by trees and plants and forest animals. Trees and plants provide shelter and food for insects, birds and animals. The land in turn provides food for fish. A polluted stream can't support returning salmon, and without salmon, the cycle of nutrients is broken.

What is stormwater?

When rain lands on roads and rooftops it becomes stormwater runoff, picking up pollutants on the way to a stream or Puget Sound. These pollutants affect the health of fish, aquatic insects, clams and many organisms. Stormwater engineers have developed many ways to store runoff and remove some pollutants from runoff, but the fact is, once stormwater picks up pollutants, it is impossible to remove all of them.

The key is to prevent the rain from becoming runoff by making the rain infiltrate into the soil where it lands. Rain gardens are an attractive option designed to help infiltrate and treat stormwater runoff onsite, and new ways of designing neighborhoods and streets using less pavement, and now, porous pavement that absorbs water is the way of the future. 

Learn more about impervious surfaces by reviewing our printer-friendly Impervious Surface Reduction Study. Conducted in 1995, the study identifies strategies for impervious surface reduction in Olympia and the surrounding north Thurston County urban growth management area. Partially funded by the Washington State Department of Ecology through a Centennial Clean Water Fund Grant, this report summarizes the results of the study and offers recommendations based on study results. The study consisted of three basic tasks: project management, involvement and education, and technical and policy analysis.

Need more information?

Contact Eric Christensen at 360.570.3741 or via email.

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Contact Information:

• Visit our City Services page for links to other City services and contact information (phone numbers).
• Contact us at publicworks@ci.olympia.wa.us.