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Stream Impacts. Many of our streams and rivers have been channel changed, dammed, or polluted At least half of our total stream miles are degraded in some way Many are not fishable or swimmable due to pollution or other alteration. Stream Impacts. Because highways frequently follow
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Stream Impacts • Many of our streams and rivers have been channel changed, dammed, or polluted • At least half of our total stream miles are degraded in some way • Many are not fishable or swimmable due to pollution or other alteration
Stream Impacts • Because highways • frequently follow • stream valleys, they • often impact streams • and riparian • vegetation
What is Stream Restoration? • Stream restoration attempts to re-establish the general structure, function, and self-sustaining behavior of a stream to a better functional condition, stabilizes or reverses stream aggradation or degradation, and enablesmore productive, diverse, aquatic habitats. Approaches include: • Removal of low-head dams or other watershed disturbances that are causing stream instability
Installation of structures and planting of vegetation to protect streambanks and provide habitat • Reshaping or replacing unstable stream reaches with appropriately designed stream channels and floodplains.
Stream Mitigation in the National Mitgation Action Plan • Mitigation for impacts to streams • Compendium of technical approaches to condition assessment • Stream mitigation protocols • 50 techniques from across the country • Being evaluated/sorted • Resource manual – with selection key
Widely Used Stream Assessment Approaches • Rosgen approach – based on physical hydrology and reference streams – does not include biological assessment • Proper functioning condition – includes biological indicators NOTE: May falsely assume that the stream reach under consideration was once in “proper functioning condition”
Programmatic Stream Restoration • Provides ecological gains where they are most needed and can be sustained • Can be Focused on statewide, regional, or watershed conservation priorities: • important habitats • water quality, • saving key parcels from development or degradation
Programmatic approaches • §Improves project delivery and streamlines Section 404 permitting • §Makes the process more predictable; sets expectations and commitments for all parties
Section 404 Jurisdiction • Waters of the United States subject to Section 404 • Streams adjacent or tributary to all navigable waters and interstate waters • Streams which are tributary to aquatic resources significant to interstate commerce
Mitigation • Permits can be conditioned requiring mitigation for fill in streams • Activities so required are eligible for Fedaid funds • Restoration of previous impacts due to Federal aid projects also eligible on currrent projects (“4r” provisions up to 20 percent of project costs)
FHWA website • Restoration of Fish Habitat in Relocated Streams • http://www.fhwa.dot.gov/environment/fish1.htm • Case Histories in Stream Restoration using modern techniques: The Effects of Highways on Streams