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developed, there was a steady loss of stream habitat for anadromous fish and stream water 

 quality was degraded in many areas. Agriculture, forestry, mining, railroads, roads, towns, and 

 cities have all taken their toll on our native fish stocks. 



Roads and railroads in the Northwest generally follow streams or flood plains. Many of them 

 are located in the riparian zone (trees, brush, and grasses that grow alongside streams and 

 benefit from greater soil moisture) of streams. These roads and railroads have directly reduced 

 stream habitat and influenced stream hydraulics so that the salmonid habitat has been simplified. 

 Sediment loads to streams have been increased by storm-related landslides. 



Land settlement in the Pacific Northwest began in the 1860s and increased rapidly through 1900. 

 Almost 10 million acres of crops and 50 million acres of rangeland occur in the area today. 

 Irrigated lands comprise about 4 millions acres. Irrigation with associated erosion of sediments 

 and runoff of farm chemical and toxins is a serious problem. Gully erosion and drainageway 

 bank failures are not uncommon. Agricultural rerun flows adversely affect stream water quality 

 in all of our river basins. Water quality sampUng identified problem areas, and agricultural lands 

 predominated these areas. Parameters and pollutants of concern were temperature, dissolved 

 oxygen, turbidity, dissolved gasses, pH, pesticides, and toxins. 



Agricultural sediment runoff into streams is mostly associated with storms. Estimates of 

 sediment runoff into streams from agriculture, in comparison to forestry, range from 2:1 for 

 pasture lands in good condition, such as those in the Tillamook Bay basin rivers in Oregon. 

 Agricultural soil losses are impossible to prevent. Typical losses range from 0. 1 ton per acre per 

 year for light pasture use to 16 tons per acre per year for typical crop rotation. Steepness and 

 length of slope, plant protection, seasonal precipitation, soil type, and the actual uses of land 

 (especially tillage methods and frequency) all affect soil erosion and runoff into streams. 



Grazing significantly affects soil erosion and degrades native salmonid habitat. By 1900, 

 overgrazing occurred in most Pacific Northwest valleys, and livestock were concentrated along 

 streams. Quality of salmonid stream habitat quickly degraded. Past range practices degraded 

 much riparian habitat, especially in range and forest lands east of the Cascade Mountains. 



Major valley areas of western Oregon and Washington had been logged by 1900 and converted 

 to farms. Private agricultural lands generally are in the flood plains and these generally were the 

 most productive and complex salmonid habitats before European settlement. Beavers were parfly 

 responsible for the habitat diversity and productivity. Fur trappers quickly reduced beaver 

 numbers and settlers converted the complex flood plains into agricultural lands. Trees were cut 

 for lumber and firewood. Channels were straightened and armored for flood control. For 

 example, about 75 percent of the complex original shorelines of the Willamette River in Oregon 

 were lost to agricultural practices and to channelization for local flood control to protect 

 agriculture. Similar losses occurred in Washington. 



Chemicals are commonly used in agriculture and ratios of chemical use in agriculture and 

 forestry have been recently estimated. Pesticide runoff ratios for agriculture and forestry in 



