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oonllD9 Photo Plate 3 Tnis pair of streams would normally have grass and brush covers. The upper stream with stable banks, overhanging vegetation, and deep undercuts, provides critical habitat for fish when times get tough, like during low flows and summer heat or winter cold. The vegetation protects the banks and helps provide a stream channel that is relatively narrow and deep. The lower stream has been grezed to the point that nearly all vegetation has been removed. Without protective vegetation, the stream channel becomes wide and shallow. There are also two detrimental effects caused by local rains: surface runoff flushes manure and sediment directly into the stream and the loss of available water from runoff reduces forage plant growth. The lower site would need at least 70% plant cover (live and dead) to minimize the problem (EPA 1979). Photo Plates 4 and 5 The upper photos display pool habitats essential for adult fish. Robust Stream Health means pools are deep enough to protect adult fish, including the largest individuals, during summer heat or winter cold. If deep pools and stable shores are eliminated by sedimentation or land use, as shown in the lower photos, Stream Health declines rapidly. The sediment in Photo 4 (lower) also indicates a problem that is accelerating as more roads are heavily sanded in the winter. Given the miles of roads buil t next to streams, the problem is major and can only get worse. Photo Plate 6 These photos continue the theme of bank protection. The lower photo demonstrates the obvious lack of balance between stream power and the erosion resistance of bank materials and vegetation. Where the brush community still survives, there is still a measure of bank protection. The consequences include the loss of stable shore, fi II ing of pools, and loss of fish food. Photo Plate 7 These photos compare streams that have been partially or completely diverted. Drying up perennial streams is a common occurrence, especially in areas with short water supplies. Whatever the benefits, there are consequences. In studies done by the Water Resources Council, a task force of state and federal agencies created in the mid 1960's, the conclusion was that retaining about 30% of total stream flow in the stream would provide for good survival habitat for most aquatic species and maintain riparian vegetation (USFS 1981 p295; WRC 1978, p130). That is, removing 70% can be done without major aquatic ecosystem collapse if the remainder was used for a baseflow and some periodic bankfull flows to maintain the channel. The in-stream flow issue has several long-term ramifications and remains a controversial legal and political topic. Text Page 7 , ~ >.h;;;