153. Administration and enforcement of the Clean Water Act stormwater provisions occur at <br />the state level, through National Pollutant Discharge Elimination System (NPDES) <br />permitting requirements. Applicable jurisdictions are required to obtain an NPDES <br />stormwater permit from the Oregon Department of Environmental Quality (DEQ, and. <br />prepare a water quality plan outlining the Best Management Practices (BMPs) to be taken <br />over a five-year permit period for reducing stormwater pollutants to "the maximum <br />extent practicable." <br />164. Stormwater quality improvement facilities are most efficient and effective at intercepting <br />and removing pollutants when they are close to the source of the pollutants and treat <br />relatively small vohunes of runoff. <br />17-5. The Clean Water Act.requires states to assess the quality of their surface waters every <br />three years, and to list those waters which do not meet adopted water quality standards. <br />The Willamette River and other water bodies have been listed as not meeting the <br />standards for temperature and bacteria. This will require the development of Total <br />Maximum Daily Loads (TMDLs) for these pollutants, and an allocation to point and non- <br />point sources. <br />1.9-6. The listing of Spring Chinook Salmon as a threatened species in the Upper Willamette <br />River requires the application of Endangered Species Act (ESA) provisions to the <br />salmon's habitat in the McKenzie and Willamette Rivers. The decline in the Chinook <br />Salmon has been attributed to such factors as destruction of habitat through <br />channelization and revetment of river banks, non-point source pollution, alterations of <br />natural hydrograph by increased impervious surfaces in the basin, and degradation of <br />natural functions of riparian lands due to removal or alteration of indigenous vegetation. <br />19-7. There are many advantages to keeping channels open, including, at a minimum, natural <br />biofiltration of stormwater pollutants; greater ability to attenuate effects of peak <br />stormwater flows; retention of wetland, habitat, and open space functions; and reduced <br />capital costs for stormwater facilities. <br />204-9. An increase in impervious surfaces, without mitigation, results in higher flows during <br />peak storm events, less opportunity for recharging of the aquifer, and a decrease in water <br />quality. <br />214-9. Stormwater systems tend to be gravity-based systems that follow the slope of the land <br />rather than political boundaries. In many cases, the natural drainageways such as streams <br />serve as an integral part of the stormwater conveyance system. <br />222-0. In general, there are no programs for stormwater maintenance outside the Eugene and <br />Springfield city limits, except for the Lane County roads program. State law limits <br />county road funds for stormwater projects to those located within the public right-of-way. <br />2324. Filling in designated floodplain areas can increase flood elevations above the elevations <br />predicted by Federal Emergency Management Agency (FEMA) models, because the <br />Laurel Ridge Record (Z 15-5) TTT_C,_'7 Page 233 <br />