Agenda - 01-27-2015 - 1 - Laserfiche WebLink

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January 21, 2015 Attachment C 12 6. Orange County Participation Although many of the Best Management Practices (BMP's) to mitigate flood conditions and as an added benefit reduce nutrient runoff may be relegated to smaller scale case by case upstream retrofits, Orange County can understand the benefits of flood control and water quality as it affects a larger regional or sub - regional context. The social, health and emergency service impact of flooding can impart a burden on the larger community. Larger scale, publically sponsored flood /stormwater BMP's on public land or easements that can ameliorate flood events is a potential joint participation project. These projects often have environmental benefits also by enhancing wetlands or recreating natural floodplains. • Whereas certain development impacts have regional implications other than human service, such as implementing the goals of nutrient reductions in Jordan Lake or flood controls and burdens when residents are impacted by flooding, Orange County respectfully makes the following suggestions for project inclusion- 1 . Chapel Hill is encouraged to consider inclusion of state of the art peak flow attenuation and best management practices ensuring post - redevelopment reductions in both stormwater impacts and nutrients (nitrogen and phosphorus), in addition to the normal State required controls on suspended solids. 2. Consideration should be given to some stream restoration through the property, re- establishing or creating floodplain benches to mitigate flooding potential within the property, as well as providing benefits upstream and downstream. At the very least, low- value, non - structural improvements on these areas should be considered, such as use as overflow parking. Perhaps some novel uses of permeable paving technologies could be employed in such areas, with accommodation for closure during anticipated periods of high stream flows. 3. Examine the location of stormwater and flood control BMP's whether on public or private property and whether on -site, upstream or downstream. Consider initial capital and ongoing regulated maintenance. 4. We are confident Chapel Hill will require minimum freeboard to occupied floor space in those areas subject to flooding from the 100 -year storm. Orange County encourages a minimum of 2 feet be considered, if not already Chapel Hill's policy. 5. Flood storage at Eastwood Lake with telemetric flood control weirs.