Stormwater pond assessment Stormwater pond assessment

Stormwater pond assessment procedure

Photo of a wet detention pond

Stormwater ponds are common treatment practices that have been installed in communities for years. The municipal separate storm sewer system (MS4) General Permit requires permittees to develop procedures and a schedule to determining the total suspended solids (TSS) and total phosphorus (TP) treatment effectiveness of all municipally owned/operated stormwater ponds (MS4 General Permit Part III.D.6.d.). The schedule to assess ponds can extend beyond the current MS4 General Permit term. The schedule must be based on measurable goals and priorities that you have established for your community.

Stormwater pond sediment excavation and removal activities

Maintenance is required to keep the ponds operating as originally designed. Sometimes, the maintenance conducted involves sediment excavation and removal activities. MCM 6 f the The MS4 General Permit requires specific documentation of these activities.

Resources

Fact sheets and guidance documents

• Assessing the performance of stormwater ponds - MPCA overview of stormwater pond performance assessment
• U of M Online Manual for assessing the performance of, and schedule maintenance for, stormwater treatment practices - the University of Minnesota's Online Manual for assessing and maintaining stormwater treatment practices
• U of M Online Manual for Developing an Assessment Program - Section of the University of Minnesota's Online Manual specifically related to the types of stormwater pond assessment programs and how to develop an assessment program for each

Example procedures

• Pond TSS and TP removal effectiveness procedure - City of West St. Paul's procedures for determining the effectiveness of TSS and TP removal
• Pond TSS and TP removal effectiveness procedure - City of Oakdale's procedures for determining the effectiveness of TSS and TP removal

Documentation and tracking templates

• Pond sediment excavation activity tracking template - MPCA template to document all required information related to pond sediment excavation activities at municipally owned or operated stormwater ponds