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Oi1aaas The knowledge regarding stream impacts from roads and the technology to prevent damage has been around for at least a century. "Ruinous sand" was known to be a major factor in the decline of fisheries at least as early as the 1930's. Forest Service handbooks in the 1930's and 40's dealt extensively with erosion control and reducing the time bare soil was,exposed to rain storms. Even laws passed as early as 1911 recognized stream sedimentation as a major problem. The concern, specific to roads, was finally brought to a head with the revision of CWA s404 in 1977. Although there is some disagreement as to who should do what, the law itself is pretty clear about requiring best management practices, assuring no stream impairment without a S404 permit, and minimizing aquatic cumulative effects. A few of the more pertinent regulations include: locating roads far enough away from water bodies to minimize damage, installing road crossings to withstand the expected floods, not disrupting aquatic species migration, stabilizing road fills during and after construction to prevent erosion, removing temporary road fills completely when the road is no longer needed, and avoiding discharges into critical habitat or special aquatic sites. Good management systems encourage the types of pollution control and land use that make future pollution control easier. This has to include operating with low total yields and full control of temporary pollutant yields. In the case of sediment, there are no temporary effects - sediment doesn't evaporate and the fish don't eat it - so it remains part of the stream system. The age-old practice of flushing is not a solution, but merely a way to pass-the-buck down stream, and in the case of reservoir sedimentation, to future generations. Photo Plate 1 These photos indicate some rather typical solutions when the stream is in the way. Although both construction sites were expected to "heal," that has not happened. In the upper photo, road ditch water continues to gully the side cast material. In the lower photo, bank erosion on this 25 year old channel change on Interstate 70 in Colorado, is still active. Photo Plate 2 This is a comparison of two reaches on the same stream. The lower photo shows conditions 25 years after road, construction moved the stream. Major erosion problems developed immediately and riprap was added to stabilize the banks. But even after 25 years, and a lot of riprap, stability problems continue. One could speculate that the entire channel reach will be riprapped by the time bank stability is actually achieved. Notice also there is still a near total lack of stream bank vegetation which affects several aquatic processes that are dependent on organic matter and influenced by heat and light. Text Page 6 iL,_<~