Wetlands on the Palouse
Consider the Palouse Country of eastern Washington and northwestern Idaho. You'll find potholes in the western part of this region-little dips and pockets in the land where water collects. You'll also find riverside wetlands. And as you ascend the mountains that border the eastern Palouse, you'll find wetlands scattered through the forests. Formerly, large areas of the Palouse were seasonally wet meadows that supported vast expanses of camas, but most of these wet meadows have been drained.
The Palouse region features both palustrine and riverine wetlands. Riparian wetlands provide wildlife habitat along the Palouse and Potlatch Rivers. Look for small, isolated wetlands among the rolling hills and on the sheltered side of steeper hills. Most of these are now vegetated with non-native pasture grasses.
Palouse Problems
Once a landscape of rolling hills dotted with pocket wetlands and rivers marked by the greenery of riparian areas, the Palouse region of the Intermountain West has lost almost all of its wetlands (an estimated 97%!). As a result, animals and plants that were once common remain only in remnants of wetlands that are mostly unprotected.
What happened to this once wetland-rich region? It's a familiar story across the western United States. When European-Americans settled this region in the late 1800s, they farmed only the drier meadows. But water tables eventually dropped, and the wet meadows became dry enough to plow. Since 1900 and the advent of intensive agriculture, 94% of native vegetation has been lost, prompting a US Fish and Wildlife publication to label the Palouse prairie an endangered ecosystem. In the mid-twentieth century, the federal government, in a push to increase crop production, encouraged farmers to drain wetlands and apply fertilizers to boost acreage
Photo: © Penny Morgan |
and production. As the native grasses were plowed under and replaced by crops, less water was captured and slowed by the vegetation. Even today, the Palouse prairie has one of the highest soil erosion rates in the country, and streams in the Palouse River basin have poor water quality.
The result? Faster runoff, increased water velocity in streams and rivers, and deeper floods that subside faster. Sediments and agricultural pollutants now wash into the waterways, fast-moving waters cut into river banks and deepen channels, and less water remains to recharge groundwater. Meanwhile, city and county governments in both Idaho and Washington grapple with increases in the frequency and severity of recent flooding. Restored wetlands would provide "ecological sponges" for sediment and nutrient loss, reduce hydrologic flashiness in watersheds, and provide wildlife habitat in diversified agricultural landscapes.
Photo: © Carolyn Duckworth |
In the Palouse and similar agricultural areas, it is difficult to find existing healthy wetlands that can serve as references for monitoring success of restoration efforts. In one study, scientists used soil maps, topography, old survey records from between 1869 and 1874, and Geographic Information Systems (GIS) technology to determine the previous extent wetlands on the Palouse. View their final report online. [PDF Document, 417 KB] .
This project provided a useful tool for mapping where wetlands once were (and therefore many potential sites for wetland restoration). These scientists also created a list of the plant species once common in these wetlands, a report on camas meadows, and educational resources including a booklet "Wild About Wetlands," a poster and the website you are now enjoying.
Another component of the project was creating pictures that illustrated what the wetlands on the Palouse may have looked like pre-European settlement, and what they could look like in the future with restoration. Click here to see those images!
This project was funded by the U.S. Environmental Protection Agency and the Idaho Department of Fish and Game.
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