Watershed’s important role in our ecosystem | Waterways

Each one of us is in a watershed every day as we move on the landscape between home, work, shopping and school.

Each one of us is in a watershed every day as we move on the landscape between home, work, shopping and school.

In some places, the watershed boundary might be very obvious. Others, not so much.

What is a watershed anyway?

A watershed can be described as a physical feature, the common drainage area for all rainwater, and shallow groundwater flows toward a stream, wetland, or other body of water. It was described by geologist John Wesley Powell (1834-1902) as “… that area of land, a bounded hydrologic system, within which all living things are inextricably linked …”

While the movement of water defines it, the system it outlines is more than just a line on a map. The size of the watershed, the nature of the water flow within it makes each watershed unique.

In Kitsap County, we have no large river basins like other Washington counties. All our watershed areas are organized around creeks, or ravine or wetland systems that drain directly into Puget Sound.

In North Kitsap south to Silverdale, there are at least 21 named watersheds and many unnamed watersheds that contribute flow to Puget Sound. The most well-known of the watersheds in the Greater Kingston area is Carpenter Creek, Grovers Creek and Kitsap Creek. Going north to Hansville we have Little Boston Creek, Silver Creek, Finland Creek and Buck Lake.

There are many areas that are systems of wetlands that are hydrologically connected to each other and to an outlet, such as the large wetland complex in the center of Hansville, and the Doe Keg Wats wetland and marsh system in Indianola.

Each one of these watershed areas represents an important part of the larger ecosystem of Puget Sound. They are places where water flows, slow or fast, bringing nutrients, oxygen and the building blocks of habitat (wood, sediment, organic matter) for all the organisms that live in our waterways, forests and beaches.

Here are some of the statistics on our local watersheds:
Carpenter Creek is 3 square miles in area. It is 71 percent forested, 6.2 percent impervious surface (where water cannot penetrate the ground, like roads, houses, parking lots), 21.3 percent turf or field, and 5 percent wetlands. It gets an average of 35 inches of rain a year. The rainfall is the same for Grovers Creek, but these watersheds get more rain on average: Dogfish Creek in Poulsbo, 36.3 inches; and Clear Creek in Silverdale, 40.5 inches per year.

Clear Creek is a larger watershed, 8.6 square miles, but as you might guess, it is 22 percent impervious (all those parking lots and stores), 9.1 percent turf, and 4 percent wetlands.

Grovers, Dogfish and Clear Creek all support five different species of salmon. Carpenter was previously thought to support three species, however, it appears it might support more.

The size of these watersheds has been estimated to date by using calculations from older surveys. Newer efforts to map watersheds are under way. They involve walking the full length of the streams to identify stream connections, wetlands or artesian springs not previously known to be hydrologically contiguous (connected above or below ground) to the watershed.

These more subtle connects can be very important to stream health because they can contribute cool, clean waters that preserve salmon redds (nests of eggs), or cool provide pools for fish resting during migration.

So as you walk or drive around today, be curious about where the water comes from and where it goes. You may be surprised.

For more information on what watershed you are in, go to www.kitsapgov.com/shoreline/maps/Watersheds_FEB2007.pdf.

— Contact Betsy Cooper at betsycooper1@gmail.com.

 

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