IEPA Source Water Protection Plan Summary and Deadlines

In 2019, Illinois Administrative Code Title 35 Part 604 Subpart C was made effective, which requires a source water protection plan (SWPP) for each community water supply that treats surface or groundwater as a primary or emergency supply of water.

Who Needs an SWPP?

Any community water supply in Illinois that:

  • Treats surface water as a primary or emergency supply of water
  • Treats groundwater as a primary or emergency supply of water

Any community water supply that has groundwater wells as an emergency water supply, even if they have never been used, must have an SWPP.

Who Doesn’t Need an SWPP?

A community water supply that purchases 100% of its water supply from another community that has already treated the surface or groundwater and does not have its own groundwater wells for emergency water supply does not need an SWPP. Re-chlorination of purchased water does NOT subject the community water supply to an SWPP requirement.

If a community water supply purchases 100% of its water supply from another community, but has emergency groundwater wells, an SWPP is required. 

What is Required in an SWPP?

  • Vision Statement –Describe community water supply’s policy and commitment to protecting source water
  • Source Water Assessment – Provide an assessment of water sources, water quality, and potential contaminants
  • Objectives – Identify measurable objectives for protecting source water
  • Action Plan – Develop description of projects, programs, and activities to meet objectives

When are SWPPs Due?

For existing community water supplies as of July 26, 2019, due dates are as follows:

  • Supplies servicing greater than 50,000 persons: July 26, 2022
  • Supplies servicing between 3,000 and 49,999 persons: July 26, 2023
  • Supplies servicing less than or equal to 2,999 persons: July 26, 2024

Baxter & Woodman recommends starting an SWPP no later than three months prior to the report due date for that service size. SWPPs must be updated and submitted for re-approval no less frequently than every five years.

For Additional Information

The Illinois Environmental Protection Agency maintains source water assessment and protection program information on its website at:

If you have questions about your SWPP, we’re ready to assist!

Mark Gockowski or
Carolyn Grieves at