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Mounds View Stormwater Pond Assessment 4 RECOMMENDATIONS July 2023 The result would be a diagnostic feasibility study that lays out data collection, methodology and results, maintenance requirements, recommendations, and feasibility -level cost estimates. It is recommended that proposed results and recommendations be presented in a public meeting to gather community input. This could be coordinated with the public meeting for the upland vegetation assessment. For a project such as this, an adaptive management approach is recommended. This means that monitoring is performed for at least one and ideally several years following implementation, in order to determine effectiveness of the improvements and whether modifications are warranted. Initial water quality assessment is proposed for only Silver View Pond. Based on City goals and desires, the approach could be applied to other ponds as directed. 4.4 PERMITTING Several permitting requirements should be considered prior to initiating any maintenance or excavation activities within constructed ponds or wetlands. Dredging permits are not required by the MPCA for dredging sediment material. The MPCA requires an NPDES Construction Stormwater Permit if the disturbance of upland area is one or more acres. A MnDNR MPARS application would likely be needed; however, if the project entails only removal of accumulated sediment, no wetland replacement would be required. The Minnesota Wetland Conservation Act (WCA) (Minnesota Statutes 8420) provides the Local Governmental Unit (LGU) guidelines for evaluating projects that involve temporary or permanent impacts to wetlands and how they should be permitted or mitigated. For example, excavation that increases the basin's surface area or depth would likely require wetland replacement. Wetland replacement may also be required if the excavation will significantly disturb the function of a wetland system. However, routine maintenance may not require mitigation if the criteria below are met. Information that may be required for determination if the project meets the criteria for a No -Loss or Exemption includes: • Materials that demonstrate whether the basin was a wetland prior to excavation for stormwater treatment or if the basin was designed and constructed within upland, • Engineering plans for the basin, if available, • Inlet and outlet information, including elevations, • Other permits obtained for pond construction, and • Sediment measurements. Projects should be evaluated in advance of the project to determine if the criteria are met. Once the materials have been provided, it can be determined if a permit or mitigation will be required. No -Loss Criteria 26