Summary of Recommendations 



depletion, and other problems. At present, im- 

 portant lakes in the Flathead Basin (including 

 Flathead Lake and Whitefish Lake) are on a 

 threshold (for references see Module B), such 

 that further increases in nutrient loading seri- 

 ously threaten their water quality. Considerable 

 efforts are being made to reduce point-source 

 input of nutrients in the Flathead Basin. This 

 has been done in an attempt to maintain the high 

 water quality that characterizes many lakes in 

 the basin. Such efforts include constmction of 

 multi-million dollar advanced wastewater treat- 

 ment plants in all major communities above 

 Flathead Lake. Similar efforts should be di- 

 rected at other significant controllable nutrient 

 sources in the basin, including land disturbance 

 activities documented in our studies and else- 

 where. 



Because of their value as a sport fishery, 

 increasing rarity across their native range, and 

 as indicators of high water quality, both bull 

 trout and westslope cutthroat trout have been 

 designated as sensitive species by the U.S. 

 Forest Service, and "Species of Special Con- 

 cern" by the State of Montana. Field evidence 

 indicates that juvenile bull trout densities de- 

 crease in streams having high substrate imbed- 

 dedness. Also, experiments of egg hatching and 

 embryo emergence (one of the most sensitive 

 stages of the saknonid life cycle) of bull trout 

 and westslope cutthroat trout reveal a direct 

 negative relationship between embryo survi- 

 vorship and the percentage of fine sediment in 

 spawning gravels. Many key spawning streams 

 already are at, or near, the threshold whereby 

 increased levels of fine sediments in spawning 

 gravels will greatiy reduce embryo emergence 

 of bull trout and westslope cutthroat trout. Fur- 

 ther study may be required to verify these rela- 

 tionships in areas outside the Flathead Basin. 



The following recommendations are an in- 

 tegration of the Historical Perspective: 



Module A — An Analysis of the Effect 

 of Timber Harvest on Streamflow 

 Quantity and Regime: An Exami- 

 nation of Historical Records and 



Module B — Evaluation of Historical 

 Sediment Deposition Related to 

 Land Use through Analysis of 

 Lake Sediments. 



and the Water Quality and Fisheries: 



Module C — The Effect of Timber 

 Management on Stream Water 

 Quality and 



Module D — Fisheries Habitat and 

 Fish Populations. 



Specific Recommendations 



Historical Perspective. Water Qual- 

 ity, AND Fisheries Recommendations 



15. Increase efforts toward continued im- 

 provement of timber harvest practices, 

 road building, and road maintenance to 

 prevent undesirable increases in ero- 

 sion, sediment transport, and nutrient 

 loadings to surface waters in the Flat- 

 head Basin. 



16. At present most timber base lands in 

 the Flathead Basin contain a network 

 of roads, some of which are maintained 

 for use, and others which have been 

 abandoned. Past construction and use 

 of roads appears to be the most signifi- 

 cant human disturbance activity asso- 

 ciated with timber management that 

 has contributed to sediment deUvery to 

 streams and lakes in the Flathead Ba- 

 sin. Therefore we recommend the fol- 

 lowing: 



A. Evaluate the existing road system 



Flathead Basin Cooperative Program Final Report 



Page 157 



