image of water quality BMPs
Examples of water quality BMPs that can be utilized to meet MIDS performance goals and can be used in the MIDS Calculator. On the left is a green roof and on the right is an infiltration swale.
image showing the MIDS Calculator user interface
Image showing the MIDS Calculator user interface.

Minimum Impact Design Standards (MIDS) were developed by the Minnesota Pollution Control Agency (MPCA) to reduce pollution and runoff through the implementation of water quality best management practices (BMPs). MIDS specifies runoff and pollutant reduction goals ( performance goals) for a variety of sites (e.g., new development, redevelopment, linear sites, etc.), providing a detailed flow chart to help designers and engineers determine applicable performance goals and evaluate treatment options. Additionally, the MPCA has developed user-friendly water quality model (the MIDS Calculator) to help designers and engineers evaluate treatment options and demonstrate compliance with performance goals.

In 2015, following a four-month process to update the City’s Storm Water Pollution Prevention Program, the White Bear Lake City Council adopted MIDS into the City’s stormwater ordinance and associated Engineering Design Standards for Stormwater Management. Adopting MIDS satisfies part of the regulatory mechanism requirement for Minimum Control Measure (MCM) 5 in the MS4 permit. The City Engineering Department, assisted by WSB engineering, incorporated guidance, recommendations, and design standards recommended by MIDS for all development, redevelopment, and linear projections creating or reconstructing 10,000 square feet of impervious area. The City’s Engineering Design Standards utilize guidance and recommendations outlined in MIDS, including the use of flexible treatment options (FTOs) for sites where infiltration is restricted (e.g., contaminated sites, sites with low infiltration capacity, etc.), the use of the MIDS design sequence flow chart to assist in evaluation and section of FTOs, and recommendations related to use of the MIDS Calculator to evaluate treatment options and demonstrate compliance.

City engineering staff have cited that the public has been supportive of stormwater requirements, realizing the importance of stormwater management to protect downstream receiving lakes and waterbodies. One barrier to incorporating MIDS standards into City ordinances was reviewing and assuring compliance with overlapping watershed management organization (WMO) stormwater rules. There are four (4) WMOs overlapping the municipal boundary of White Bear Lake, all with unique and different stormwater management rules. Ultimately, the City reviewed WMO stormwater standards and chose to adopt the most-restrictive impervious area WMO threshold.

After several years of MIDS implementation, the City is planning to update Engineering Design standards to add specificity related to preferred and recommend BMP implementation practices, stormwater reuse, and soil testing. Specifically, the City intends to add language assigning priority to above ground versus below ground treatment, address stormwater reuse as a viable volume control option, and add specific requirements related to soil testing and soil borings, pretreatment, and access (e.g., access plan for implemented volume control BMPs).

For more information regarding MIDS implementation within the City of White Bear Lake’s Engineering Design Standards for Stormwater Management, contact Connie Taillon, Environmental Specialist/Water Resources Engineer:

Project Location: White Bear Lake, MN
Completion Date: May 2015
Organizations Involved: City of White Bear Lake Engineering Department and WSB Engineering
Project Cost:

  • Staff time related to creation and adoption of MIDS standards (2015): $13,000.
  • Engineering consultant hired to assist with creating the MIDS standards and other MS4 program related setup and implementation tasks: $7,500.
  • Annual development review related to MIDS standards: $5,000 per year

Quantitative Outcomes: MIDS standards incorporated into the City’s stormwater ordinance establish volume and pollution control for all development, redevelopment, and linear construction projects.

This page was last edited on 8 December 2022, at 16:36.