More than 17,000 small acreage farms cover 298,000 acres in Oregon. Singly, one farm may cause little pollution. But added together, small acreages can significantly impact a watershed. A stream reflects your management of the land and water. Proper upland and instream measures can result in clean water for fish, drinking, and swimming. You can check the health of your stream by using your eyes and legs.
1. Water color.Clear water is often found during low flows. Muddy color occurs during high flows and when upstream activities send sediment downstream. Tea-colored water often comes from the brown tannin of decaying leaves. Colored sheen may indicate an oil spill.
2. Foam.Froth on a stream can be natural or human-caused. Natural foam has an earthy or fishy smell. Soap or detergent foam will have a perfume smell.
3. Streambed sediment.If gravel and cobbles are present, less than 25 percent of the gravel, cobble, and boulder spaces should be filled with sediment. A marginal to poor condition exists if more than 50 percent of the spaces are filled.
4. Algae color.Algae thrive on nutrients from commercial fertilizers, leaf waste, and manure. Light or dark green algae scattered in spots indicates a healthy stream. Matted or hairy algae mean
poor stream quality. Brown algae point to sediment deposits. An algae bloom indicates excess nutrients.
5. Streambank erosion.Bare spots on streambanks may indicate an unhealthy stream. Wooded streambanks seldom erode, even in high floods. Steep banks, frequent tree fall, and more than 10 percent bank erosion along a stretch of stream may indicate erosion problems.
6. Riffles.Riffles occur when water runs over rocky or rough streambeds. A mix of riffles and quiet pools provide good fish habitat. The ideal habitat for many aquatic animals is a streambed with cobbles from 2 to 10 inches in diameter.
7. Fish shelter.Submerged logs and dead trees provide good fish habitat.
8. Stream shade.Trees overhanging more than 50 percent of the streambank provide good fish habitat. Less than 50 percent indicates fair to poor habitat.
9. Stream temperature.If you have a thermometer handy, measuring a temperature less than 50 degrees is good, 50 to 64 degrees is fair, and more than 64 degrees is poor. Warm water threatens salmon, trout, and steelhead. Temperature is an important water standard in Oregon.
