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<br />PROPOSED DRAINAGE <br />Drainage <br />Area <br />2-Year Runoff <br />(cfs) <br />10-Year Runoff <br />(cfs) <br />100-Year Runoff <br />(cfs) <br />DA1 0.41 0.67 1.25 <br />DA2 0.60 0.92 1.63 <br />DA3A 0.15 0.22 0.38 <br />DA3B 0.13 0.19 0.34 <br />DA3C 0.15 0.22 0.38 <br />DA3D 0.15 0.23 0.40 <br />DA4A 0.15 0.22 0.38 <br />DA4B 0.15 0.23 0.41 <br />DA4C 0.12 0.18 0.31 <br />DA5 0.29 0.57 1.25 <br />DA6 0.38 0.75 1.64 <br />DA7 0.05 0.11 0.23 <br /> <br />The proposed filtration basin (FB1) and associated outlet structure have been <br />designed to limit overall proposed site runoff rates to overall pre-developed runoff <br />rates. FB1 outlets to the regional pond via proposed and existing storm sewer. Data <br />relating to the performance of the proposed filtration basin during 2, 10, and 100- <br />year storm events is shown in the table below: <br /> <br />FILTRATION BASIN DATA <br />Bottom of Basin 935.80 <br />Basin Outlet 938.80 <br />Top of Basin 941.00 <br />2-year Peak Water Level 938.74 <br />2-year Peak Outflow (cfs) 0.04 <br />10-year Peak Water Level 939.19 <br />10-year Peak Outflow (cfs) 0.65 <br />100-year Peak Water Level 940.02 <br />100-year Peak Discharge (cfs) 3.26 <br /> <br />A link was used to calculate total proposed runoff rates to the regional pond from <br />FB1 and DA6. Data relating to the link (L1) during 2, 10 and 100-year storm events is <br />listed below: <br /> <br />PROPOSED LINK (L1) RUNOFF RATES <br />Drainage Area 2-Year Runoff <br />(cfs) <br />10-Year Runoff <br />(cfs) <br />100-Year Runoff <br />(cfs) <br />L1 0.41 0.81 4.50 <br /> <br />The total overall proposed runoff rates, to the northeast regional pond and Foss <br />Road, are compared to the total overall existing runoff rates, to the northeast <br />61