6201 ASSOCIATED BLVD BASE FILE 2018-03-29

CITY OF EVERETT STORMWATER MANAGEMENT MANUAL Wet Ponds Date Drainage System Maintenance Activities and Conditions Frequency Feature I I I I Problem Conditions to Check For That Should Exist M General Water level First cell is empty,doesn't hold water. Line the first cell to maintain at least 4 feet of water.Although the second cell may drain, the first cell must remain full to control turbulence of the incoming flow and reduce sediment resuspension. M Trash and Debris Accumulation that exceeds 1 cubic foot per Trash and debris removed from pond 1000 square feet of pond area. M Inlet/Outlet Pipe Inlet/Outlet pipe clogged with sediment and/or No clogging or blockage in the inlet and debris material outlet piping. M Sediment Sediment accumulations in pond bottom that Sediment removed from pond bottom. (If Accumulation in exceeds the depth of sediment zone plus 6 sediment contamination is a potential Pond Bottom inches,usually in the first cell, problem,sediment should be tested regularly to determine leaching potential prior to disposal.) M Oil Sheen on Water Prevalent and visible oil sheen. - Oil removed from water using oil-absorbent pads or vactor truck. Source of oil located and corrected. If chronic low levels of oil persist,plant wetland plants such as Juncus effusus(soft rush)which can uptake small concentrations of oil. A Erosion Erosion of the pond's side slopes and/or Slopes stabilized using proper erosion control scouring of the pond bottom that exceeds 6 measures and repair methods. inches,or where continued erosion is prevalent. A Settlement of Pond Any part of these components that has settled 4 Dike/berm is repaired to specifications Dike/Berm inches or lower than the design elevation,or inspector determines dike/berm is unsound. A Internal Berm Berm dividing cells should be level. Berm surface is leveled so that water flows evenly over entire length of berm. Appendices F25