Tools and materials for partners and stakeholders interested in minimizing the impact of chloride on Minnesota lakes, rivers, and groundwater.
Reports and guidance
MPCA technical reports
- TCMA Chloride TMDL (wq-iw11-06e)
- EPA approval letter (wq-iw11-06g) (EPA approval 6/9/2016)
- TCMA Chloride Management Plan (wq-iw11-06ff) (MPCA approval 2/26/2016)
- Fact sheet on Twin Cities Metropolitan Area Chloride Management Plan
- Shingle Creek Chloride TMDL
- Nine Mile Creek Chloride TMDL
- Phase 1 Chloride Feasibility Study for the Twin Cities Metropolitan Area
- See the Groundwater data page for an MPCA groundwater monitoring report. The agency found chloride concentration above the water quality standards in 30% of the wells in the Twin Cities metro area.
- Economic Analysis of Salt Use Report
Other technical reports
- Chloride contributions from water softeners and other domestic, commercial, industrial, and agricultural sources to Minnesota waters (University of Minnesota)
- Cost and benefits of household water softening: a review (University of Minnesota)
- Regional assessment of river water quality in the Twin Cities metro area 1976 - 2015 (Metropolitan Council)
- Increasing chloride in U.S. rivers (U.S. Geological Survey)
- The reduction of influent chloride to wastewater treatment plants by the optimization of residential water softeners (Madison WI Metropolitan Sewerage District)
Chloride working group reports (wastewater)
The MPCA formed a work group of eight city representatives and two consulting engineers to study the problem of chloride in wastewater. Learn more:
- Signed Memorandum: Chloride Water quality standard and NPDES permit implementation guidance (wq-wwprm2-47)
- Chloride Work Group Policy Proposal for Minnesota: Recommendations for addressing chloride in municipal wastewater effluent (wq-wwprm2-24)
- Alternatives for addressing chloride in wastewater effluent (wq-wwprm2-18)
- Chloride permitting decision tree (wq-wwprm2-25)
MPCA surface water monitoring guidance
- TCMA Chloride Monitoring Guidance for Lakes
- TCMA Chloride Monitoring Guidance for Streams and Storm Sewers
MPCA direct assistance
The MPCA administers several programs that can assist organizations looking to address salt use and chloride pollution:
- Minnesota GreenCorps – Places AmeriCorps members with host organizations around the state to assist with a variety of environmental efforts, including reducing salt use and minimizing chloride pollution
- GreenStep Cities – A free, voluntary challenge, assistance, and recognition program to help cities achieve their sustainability and quality-of-life goals. Reducing salt use is one of the recommended best practices.
- Small Business Environmental Assistance – MPCA's program for helping small businesses meet regulatory obligations and reduce their impact on the environment.
- Clean Water Partnership loans - MPCA offers zero-interest loans to local government and tribal communities to implement practices that reduce non-point sources of chloride pollution.
Water softening rebate guide - New!
The MPCA partnered with the Nine Mile Creek Watershed District, TetraTech, several local cities, watershed organizations and local water treatment professionals to develop guidance for communities interested in developing and implementing a rebate program to reduce chloride from home water softeners. This first of its kind guide includes valuable information, resources and specific examples for implementing a successful water softening rebate program.
Model ordinances for chloride reduction - New!
The MPCA partnered with the Nine Mile Creek Watershed District, TetraTech, several local cities and watershed organizations to develop a suite of model ordinances that communities can choose to implement. There are several options to consider which are intended to assist with reducing salt pollution.
Economic analysis: Addressing chloride in wastewater
For communities working to reduce chloride in their wastewater discharges, the MPCA has developed an economic analysis of the potential solutions. It also provides useful information for municipal decision-makers, such as city councils and city managers.
Example regulatory rules, policies, and ordinances
Several organizations have implemented various rules, polices and ordinances to reduce salt pollution in their community.
- Nine Mile Creek Watershed District Rules
- Riley Purgatory Bluff Creek Watershed District Rules
- Chloride Source Reduction Ordinance, Waukesha, WI
- Ordinance and Water Softener Rebate Program, Pinckney, MI
Model snow and ice policies
The model snow and ice policy is designed to help county and city governments adopt winter maintenance policies that include protecting the environment among their goals.
- Minnesota Model Snow and Ice Management Policy (p-tr1-51a)
- Minnesota Model Snow and Ice Management Policy Guidance Document (p-tr1-51b)
- Minnesota Model Exhibit for Private Snow and Ice Service Contract (p-tr1-51c)
- Goodhue County snow and ice control policy
- City of Rochester snow and ice control
- City of Eagan snow and ice control policy
- Eureka Township snow and ice control policy
- City of Le Sueur snow removal policy
- University of Wisconsin Madison Outdoor Salt Use Policy
Model winter maintenance contract
The city of Edina developed a model contract for snow and ice management that embraces best practices to minimize environmental impacts from salt and other chemicals. Property owners can adapt the model contract to suit their needs and to ensure their contractors are protecting Minnesota waters from chloride pollution.
- Minnesota Model Contract for Snow and Ice Management (p-tr1-52a)
- Cover Letter - Model Contract for Snow and Ice Management (p-tr1-52b)
- Explanatory Memo - Model Contract for Snow and Ice Management (p-tr1-52c)
Resources for organizations engaged in education and outreach on chloride pollution.
- More Isn't always better (City of Edina) — Sometimes more isn't better. this PSA on salt use reminds Edina residents and businesses to limit the amount of salt used to melt ice in the winter.
- Chloride and our water: Monitoring the mix — Shows MPCA staff monitoring for chloride and discussing the issues with chloride contamination
- Improved winter maintenance: Good choices for clean water (Mississippi Watershed Management Organization) — Comprehensive overview of the issues with chloride pollution and how to avoid it
- The changing Earth: Chlorides in water (University of Minnesota, Water Resources Center) — A look at the U of MN research into chloride in Minnesota water, with specific information about the role of water softening.
- Watershed by The Hypoxic Punks (Mississippi Watershed Management Organization) — A music video designed to educate viewers on chloride pollution
- Safe sidewalks for pets (Wisconsin Salt Wise) — About the dangers that sidewalk salt poses to pets
Posters, postcards, and other printables
- Salt pollutes postcard
- Toolkit: Salt Smart Toolkit (Riley Purgatory Bluff Creek)
- Brochure: Fight snow and ice, pollution free (Mississippi Watershed Management Organization)
- Brochure: How to hire a contractor that uses less salt (9 Mile Creek Watershed District)
- Brochure: Choosing a deicer (9 Mile Creek Watershed District)
- Brochure: Don't pass the salt (City of Farmington)
- Brochure: Be salt wise (WI Salt Wise)
- Poster: Pledge to be salt smart (Clean Water MN)
- Tip card: Use salt wisely (Clean Water MN)
News stories and press releases
- In Morris and other cities, solving a salty problem in municipal water (MPR)
- Use de-icing salt sparingly to protect Minnesota waters
- We’re pouring millions of tons of salt on roads each winter. Here’s why that’s a problem. (Ensia magazine)
Road and sidewalk salt worries (TPT Almanac) — MPCA staffer Brooke Asleson highlights problems with salt getting in Minnesota waterways.
Rising salt levels threaten Twin Cities lakes by 2050 (Star Tribune)
Water softening resources
- Water softening (U of MN, Water Resources Center) — Information on how salt from water softening is affecting Minnesota's lakes and streams
- A Review of Residential Water Softening (U of MN, Water Resources Center) – Fact sheet
- In Morris and other cities, solving a salty problem in municipal water (MPR)
- Water Softening Best Practices Guidelines (Madison Metropolitan Sewerage District)
- Residential Water Softening Infographic (U of MN, Water Resources Center)
- Commercial and Industrial Water Softening Infographic (U of MN, Water Resources Center)
- Home Salt Reduction Brochure (Madison Metropolitan Sewerage District)
- Dane County Water Softener Upgrades – Case study about actions taken to reduce salt use through water softener tuneups and upgrades (WI Salt Wise)
- Citizen Group who advocate for strategies to reduce over salting (Stop Over Salting)
- Chloride in Communities & Watersheds fact sheet (U of MN, Water Resources Center)
- Chloride Reduction program (Madison Metropolitan Sewerage District)
Road Salt: Can we have safe roads and healthy streams? (Lake Superior Streams)