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Thie was apparently the most ecologically damaging period the Basin haB known 

 (Wendler and Deschamps 1955a). Almost all the structures were total blocks to 

 anadromoue fish and eliminated considerable spawning and rearing areas 

 (Figure 6). These barriers effectively blocked over 60 percent of the salmon 

 spawning and rearing streams of Grays Harbor. The average splash dam was in 

 place about 20 years. 



The downstream impacts included: 



(1) mechaaical injury to eggs and fish spawning below the dam, 



(2) destabilization of gravel beds by moving logs or suddenly 

 increased flows, with the resultant disappearance of distinct 

 riffles and pools, 



(3) channel instability, 



(4) deposition of bark over a large part of the stream bottom between 

 splashes, 



(5) unnatural shading of many miles of tidewater by log rafts, and 



(6) loss of fish cover by clearing woody debris from stream channels. 



In the 1930, the timber industry began undergoing a technical revolution as 

 roads and railroads began to replace rivers for log transport (Wendler and 

 Deschamps 1955b), and the dams became obsolete. Many operators abandoned the 

 installations without attempting to remove them. Some fish ladders were 

 constructed where feasible, but many did not work efficiently. Many dams 

 blocked migrating fish until they either rotted out, washed out, or were 

 removed by WDF in the early 1950s. After removal, rapid natural 

 recolonization was observed in several instances. In addition, hatchery- 

 reared fish, usually coho fry, were at times planted upstream to speed 

 recovery. 



A significant change occurred in the logging industry in 1962 when very high 

 winds blew down extensive timber, creating the need to remove a large number 

 of logs before decay set in. The permanent effect was that Japan became a 

 major buyer, and Weyerhaeuser Company a major exporter, of Chehalis Basin logs 

 (Felver 1982, quoted by Grays Harbor Regional Planning Commission 1992). 



Continuing Effects of Old Logging Practices 



Shade Removal . Economically valuable trees were usually removed down to the 

 streambank until the last decade. Until shade trees grow back, an exposed 

 stream tends to become warmer and, if it gets too warm, salmon and steelhead 

 cannot use it. If this happens to a number of streams, temperatures may 

 increase downstream as well. 



Sources of Instream FiBh Cover Removed . Lack of woody debris naturally 

 entering the stream over the years resulted in lost habitat complexity until 

 some point in the last decade. This situation especially hurts juvenile coho 

 and adult Chinook and, to a lesser extent, juvenile steelhead, because it 

 denies them instream cover. Further misguided efforts to remove logging 



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