:i) MVHIIM MAN Mil MINI 



water tcmporatiircv ami tlow regime, can seni>iisly reduce 

 priH.liic(ivit\. 1 ariiislkles, dams and diversions tor hydro- 

 eleclnc and other purfK>ses have taken a heavy toll on 

 Pacific salnK>n and other anadronmus stocks. Some ot 

 the mi>si conspicuous and de\astaiing etVects have 

 resulted tri>m landslides into spawning nvers. The man- 

 induced Hells Ciate slides of 1*^13 and 1^)14 decimated 

 the F-'raser River runs of sockeye salmon as well as other 

 stivks that depended on spawning beds above the slide, 

 especially the large runs of pink salmon. And the Babinc 

 slide ot" 1*^51, a natural event, drastically reduced the 

 Babine sockeye runs. 



Dams were constructed early in this century in igno- 

 rance ot", or with disregard to, their effects on fish, with 

 devastating results. A dam on the Adams River, built for 

 logging purposes, and i>ne on the Quesnei for placer min- 

 ing contributed to the decline in the Fraser River stocks. 

 Other, more permanent dams were built on the 

 Puntledge. Stave, Capilano, Bridge, Seton, Cheakamus, 

 Jones. Kloiyah, Nechako and Campbell rivers, and on 

 Great Central Lake. 



In the States of Washington and Oregon to the south, 

 dams and diversions have been the major environmental 

 insult to fish. In British Columbia, large hydroelectric 

 dams and flood control works on major spawning rivers 

 have been more vigorously opposed. And while the dam- 

 age from this cause has been substantial — the dams on 

 rivers such as the Puntledge had almost destroyed unique 

 runs before the hatcheries were constructed — hydroelec- 

 tric dams have caused less permanent loss of fish on Can- 

 ada's Pacific coast than have other causes of environmen- 

 tal damage. Yet, dams and diversions probably pose the 

 greatest potential threat to natural salmon stocks. 

 Whether technology will ever be developed to enable 

 large runs of fish to pass over high dams, such as those 

 that have been contemplated for the Fraser system, is 

 questionable. In any case, improved fish passage technol- 

 ogy would not prevent the destruction of salmonid habi- 

 tat. Future losses will therefore hinge on political deci- 

 sions on flood control and hydroelectric development. 



Smaller-scale diversions of water for irrigation and 

 domestic and industrial water supplies have been very 

 damaging to fish, especially in urban areas and in the 

 agricultural regions of the lower Fraser valley, on the east 

 coast of Vancouver Island and in the dry ranching and 

 fruit-growing country of the interior. The heaviest 

 demands for irrigation tend to be in the summer when 

 stream-dwelling salmonids may be already stressed by 

 low flows. Further, unless intakes are carefully screened, 

 fish pass with irrigation water into the fields and 

 orchards. 



h(iresJry 



The forest canopy that covers the watersheds of west- 

 ern Canaila protects and sustains the water systems that 

 provide fish habitat. Removal of this cover inevitably dis- 

 turbs the aquatic environment. ITie adverse impact of 

 forest development and harvesting operations on fish 

 habitat has received a great deal of attention in this Com- 

 mission's public hearings. U)gging and related activities 

 are now widely agreed to have had a greater overall 

 impact on salmon stocks than any other single source of 

 habitat damage: 



Surely the central issue which your commis- 

 sion must address is the question of how Brit- 

 ish Columbia's two great renewable resource 

 industries can co-exist without one destroying 

 the other.' 



Logging in the early decades of this century was 

 extremely destructive to anadromous fish. No controls 

 were in place to protect streams from road and railroad 

 construction, log jams and debris, log driving, siltation, 

 denudation of streambank vegetation and the many sub- 

 tle effects of cutting, yarding and transporting timber. 

 Massive loads of sediment left spawning gravel unpro- 

 ductive, and logjams and debris obstructed fish access to 

 spawning and rearing waters. The causes of some of these 

 early losses, such as log driving and dams built for log 

 transport, have since been eliminated. Many coastal 

 streams have in large part recovered through years of 

 natural rehabilitation and forest regrowth. 



The heavy timber on the mountainous west coast can- 

 not be logged without causing some, at least temporary, 

 disturbance to the aquatic environment, even with the 

 best practices. The forest industry has expanded to a vast 

 scale in British Columbia, clearcutting 300 to 400 thou- 

 sand acres annually. And much of this logging has pro- 

 gressed beyond valley bottoms into the high elevations, 

 steep slopes and unstable soils of the headwaters, posing 

 new threats of slides and stream destabilization. 



Forest operations are so pervasive in British Columbia 

 and leave such an abrasive visual impact on the land- 

 scape, that they are widely held to be a major cause of 

 declines in salmon stocks. Certainly, logging practices in 

 the past had little regard for fish habitat and, as I have 

 noted, were destructive to fish. Even now, examples of 

 careless and unnecessarily damaging logging and road- 

 building practices recur. But the scientific evidence avail- 

 able from careful studies of the impact of logging on fish 

 habitat, like the Carnation Creek project on Vancouver 

 Island and others in the United States, contradict some 

 superficial impressions. For example, these studies show 

 that clearcutting does not necessarily result in reduced 

 runoff; that stable large debris in streams is normal and 

 creates the pools needed for overwintering fry; and that 



