Item 9: Ordinance Concerning Stormwater Development Standards

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and effects from bioaccumulative chemicals). Although the draft basin plan predicts a 58% increase in pollutant load as a result of future development, the water quality conclusions in the draft basin plan were made based on generalizations from data collected in other basins. Without adequate baseline data on how well our natural drainage system is working and where the pollutants are entering, how can we create a strategic plan to improve the functioning of our system and bring us into compliance with the NPDES permit? Open waterways in this basin connect directly with the Willamette River and have been identified as likely salmonid habitat by the Long Tom Watershed Council. As yet there is insufficient data on existing aquatic. species in the open waterways ofthis basin and how stormwater quality affects their survival. · CAPITAL PROJECTS OR DEVELOPMENT STANDARDS? According to our draft basin plan, the results of all the other basin plans has "been to implement the capital project alternatives and not implement flood control development standards" (p.3-8). In RR/SC we do not have the infrastructure to improve for controlling flooding. We rely on open waterways, sloughs, wetlands and water infiltration to accommodate our stormwater. We can not allow the filling of our swales, waterways and wetlands and expect to accommodate the runoff from the projected amount of impervious surface for our basin. Replacing culverts with larger culverts will not meet our stormwater conveyance goals. Pervious surfaces, native soils and vegetation, and water channels allow for infiltration of precipitation and greatly reduced velocity of stormwater flow thereby reducing the risks of flooding and simultaneously reducing the need for "stormwater facilities" that require capital expenditure, ongoing maintenance, and inevitably replacement. . THE BASIN PLAN AND THE ORDINANCE The RR/SC basin plan strategy is not reflected in the proposed ordinance. In particular, the basin plan goals of (1) reducing pollutant loads associated with new developments through development standards and (2) identifying, protecting, and managing significant open waterways for their beneficial stormwater functions. The proposed ordinance focuses on engineered and built facilities to manage quality and quantity of stormwater instead of specifically prioritizing preservation and enhancement of existing natural stormwater drainage components which effectively control both quality and quantity of stormwater. The ordinance is the tool used to implement the goals of all the basins, but without a completed basin plan, our basin's needs are not addressed. . THRESHOLD FOR THE REQUIREMENT The 3000 square foot threshold for pollution control facilities requirement is too large and the rationale for its use (that it matches current categories for SDC and user fee categories) is not compelling. The effects of stormwater runoff are cumulative, and the goals to minimize the deleterious effects should inform the threshold, not that it's a number that "developers are familiar with". The majority of stormwater runoff is from residential sources. Most development in our basin happens when builders buy individual lots from a developer or when existing lots are divided to allow the building of another residence. Subdivisions are not developed all by the same builder or at the same time. In this case, each lot would need to pass the 3,000 sq. ft. threshold before these