Storm Water Project Update
The Phase I design will include a Mechanical Treatment Device (MID) in the Right-of-Way along the east side of Drake Road which will capture coarse sediment and require twice-per-year cleanout. The Council has been in discussion with the City to manage these cleanouts. The discharge from the MID will be directed to the east, traversing <0.33 acres of wetland, to a hydraulic equalization basin and then into a 1,000-ft infiltration trench along the northern shoreline of the lake just upgradient from fringe wetlands along the lakeshore. (Crossing the wetland will require a permit from EGLE.) This system will have emergency overflows from the MFD for storms greater than a I0-yearpeak rainfall (about 3 inches) but will otherwise remove 100% of the sediment (and attached P load) in smaller events. The MFD/infiltration trench design is considered the most effective approach to address these untreated flows with the smallest effective footprint. Wetlands and uplands in proximity to the trench have been delineated and surveyed such that the infiltration trench will be constructed on ALPMC property to have minimal ecological impacts/maximum treatment.