fish habitatWater-typing is the name for a process of identifying and cateorizing streams, lakes, and wetlands in terms of their importance for biodiversity and human use. It’s a pretty basic inventory developed by the Washington Department of Natural Resources in the 1970s, and it works, but only when it’s done right.

The accompanying image shows what happens when it’s done wrong. In January, this important habitat for fish was logged without any protection simply because the map was in error: it failed to show that this stream supported fish. Normally, this sort of waterway would have at least received a 58 foot buffer. An important regional group, the Wild Fish Conservancy (the author of the photo), has demonstrated that the original maps underestimate the actual miles of fish-bearing streams statewide by up to 50 percent!

Grist relies on the support of generous readers like you. Donate today to keep our climate news free. All donations matched!

It’s not just about logging, either. Accurate maps would help city and county agencies regulate new developments more accurately, too. Right now, suburbia creeps too close to many watersheds that are mischaracterized or which simply don’t appear on the maps at all.

What happens next is up to the WDNR, perhaps, but thanks to the diligence of the grassroots, it’s now clear that they need to clean up their data, for the health of Puget Sound.

Grist thanks its sponsors. Become one.