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35 Rain Gardens – Typical maintenance activities include, pruning (spring/fall), replacing plants, adding mulch, pulling weeds, removing sediment, removing trash and inspection. Per the Municipal Separate Storm Sewer System (MS4) Permit, inspection of rain gardens should occur annually. Public Works needs to develop an updated rain garden location map and create a plan for future maintenance. Current maintenance is ordered “as-needed”, addressed with the Street Maintenance Plan areas or at rain gardens in highly visible areas. Surface Water Ponds – Maintenance activities include removal of excessive vegetation, removal of trash/debris and removal of sedimentation or dredging. Adequate access must be provided for inspection, maintenance, and landscaping upkeep, including appropriate access needs for equipment and vehicles for when more extensive repairs are required. Primary issues we look for during inspections is clogging of the inlets and outlet, weir structure condition, erosion and gulley formation, sedimentation build up and undercut of adjacent roadways or trails. Per the MS4 Permit, inspection of surface water ponds should occur once with each permit cycle which is typically 5 years. Public Works needs to develop an updated surface water pond map and create a plan for future maintenance and rehabilitation projects. Currently, pond maintenance and rehabilitation is included in the City’s PMP projects. Outfall condition Inspection – Following the MS4 Permit, the City is required to inspect every municipal outfall (outlet/inlet) once with each permit cycle which is typically 5 years. Arden Hills currently has 439 outfalls inventoried so we will inspect roughly 90 structures each year. Through inspection, a report is created to address condition, repairs needed, odor detection or inflow & infiltration concerns. Grit Chambers – Public Works inspects and cleans every grit chamber annually. Grit chambers can be in the form of a baffled structure, separated tanks or a simple sump style. It is important to clean these structures more frequently as they are an important factor in promoting water quality by separating sediment and other debris before reaching our water bodies. These are also typically installed directly upstream from ponds to help reduce prolong the time needed for costly dredging activities. Public Works is currently updating inventory of existing grit chamber structures. Open Ditches & infiltration basins follow the same maintenance activities. Inspection for repairs or erosion issues, remove debris and vegetation removal. Catch Basins – Public Works conducts full structure inspections every 5 years to address any repair needs. Issues to look for are inflow & infiltration, settling of surrounding pavement or curb, cracking of interior structure concrete, drain tile cleaning and any blockage with flow. Storm sewer mainlines – Inspection via televising camera is conducted on an as-needed basis. Full inspections are completed prior to Pavement Management Program (PMP) projects to identify any structural repairs needed. Grading and Erosion Control Permit management – Following City Ordinance Chapter 15 (Erosion and Sediment Control) along with MS4 requirements, construction site inspections are conducted for all land disturbance activities for both residential projects and developments as defined within the ordinance. These inspections ensure that the permit holder is staying in compliance with what is required for erosion control and helps promote water quality. Gopher State One Call locates for structures, sewer main along both City and County roads.