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<br />l <br /> <br />tion standards in force in several watershed communities were inadequate to prevent increases in <br /> <br /> <br />downstream flooding. Finally, the study identified significant areas of natural storage upstream. If <br /> <br /> <br />this storage were to be removed, flood damages in our watershed would go up by 50% or more. <br /> <br /> <br />Recognizing their vulnerability, downstream communities requested the cooperation of all the <br /> <br /> <br />towns of the watershed to continue to work together to prevent flooding from becoming worse. <br /> <br /> <br />Fortunately, communities responded positively; the study had driven home the fact that flooding <br /> <br /> <br />is a watershed problem that begins when the first raindrop hits the upland. <br /> <br /> <br />MULTI-OBJECTIVE GOALS Our Committee first established the following goals that clearly <br /> <br /> <br />layout the multi-objective nature of our work: <br /> <br /> <br />1. Reduce flooding and minimize streambank erosion in the Butterfield drainage basin. <br /> <br /> <br />2. Protect the storm and floodwater capacities of natural detention areas and protect wetlands. <br /> <br /> <br />3. Preserve public open space to increase recreational opportunities (including trails), protect and <br /> <br /> <br />enhance natural resources, and improve the environment of communities and neighborhoods. <br /> <br /> <br />4. Improve stream maintenance to maximize natural resource benefits and aesthetics. <br /> <br /> <br />5. Improve the quality of water in Butterfield Creek and its tributaries. <br /> <br /> <br />6. Achieve a mutually supportive, basin-wide management and regulatory framework for develop- <br /> <br /> <br />ment activities affecting Butterfield Creek <br /> <br /> <br />TAKING ACTION With goals adopted, our next step was regulatory. We needed to address those <br /> <br /> <br />critical issues pointed out by the engineering study. The Butterfield Creek Model Floodplain and Storm, <br /> <br /> <br />water Management Code was published in November, 1990 and has since been adopted by all five of <br /> <br /> <br />the critical upstream communities of the watershed. Here are some highlights of our model code: <br /> <br /> <br />. We are requiring that the storage capacity of those all important natural storage areas be main~ <br /> <br /> <br />tained. Because portions of these areas are outside wetlands and floodplains, they were previously <br /> <br /> <br />unregulated. Now, any construction on these properties will require compensatory storage to make <br /> <br /> <br />up for lost natural storage. This is in addition to the usual detention requirements. <br /> <br /> <br />. Detention requirements have been significantly strengthened. We have beefed up detention standards <br /> <br /> <br />to match real world conditions. Release rates must meet laO-year storm limits of 0.15 cubic feet per <br /> <br /> <br />second per acre and two-year storm limits of 0.04 cubic feet per second per acre. The two-year <br /> <br /> <br />requirement is aimed at stabilizing runoff rates to prevent increased erosion of downstream channels. <br /> <br /> <br />. The adverse water quality effects of development are addressed by requiring effective soil erosion <br /> <br /> <br />and sediment control, encouraging "natural" drainage practices such as swales and vegetative <br /> <br /> <br />filters, al1d specifying detention basin designs which enhance pollutant removal. <br /> <br /> <br />. Our regulatory floodplains have been expanded to coincide with those demonstrated by the engineer' <br /> <br /> <br />ing study. The revised mapping has also been adopted at our request by the State regulatory agency. <br /> <br /> <br />. We have limited uses in the floodway, allowing only public flood control, public recreation and <br /> <br /> <br />open space, crossing roads and bridges. <br /> <br /> <br />Sue c e 5 s S tor i e s 1 1 <br />