South Fork Newaukum Watertype Assessment

In cities and counties throughout Puget Sound, western Washington State, water type classification (such as “fish bearing” or “non-fish bearing”) directly affects the amount of protection that streamside buffers receive through local governance.

Too often, however, these streams do not receive the protection they should for a surprisingly simple reason: policy makers are relying on inaccurate maps.

Errors in Washington State water type maps result in the under-protection of 40-60% of the fish-bearing stream network. Over the 105 miles of streams in this study area, Wild Fish Conservancy (WFC) found that 4.6 miles of those Washington Department of Natural Resources (WDNR) mapped channels did not exist, but that an additional 16.2 miles of stream channels did exist that were not on the official WDNR water type maps.

Using visual and electrofishing surveys by state-established protocols, WFC documented and corrected water type classifications in approximately 123 miles of at-risk streams within the South Fork Newaukum watershed.

Using GPS and GIS, WFC accurately mapped previously unmapped/incorrectly mapped water courses to ensure informed and responsible watershed management. The assessment results were submited to WDNR and uploaded into a web-based interactive GIS available to planners, landowners, and resource managers.

In addition to correcting water type maps, this assessment benefited salmon by generating species-specific fish distribution data for cutthroat trout, rainbow trout, coho salmon, sculpin, brook lamprey, 3-spined stickleback, brown bullhead, koi, and dace.