CWLP - City of Springfield Supplemental Water Supply Project

Supplemental Environmental Impact Statement (SEIS)
Public Information & Involvement Resources
Misty Buscher - Mayor


1. What is the City of Springfield’s Water Supply System?

The City of Springfield, City Water, Light & Power (City) operates an integrated water supply, purification, transmission, and distribution system. The City’s service area encompasses approximately 100 square miles with more than 52,600 service connections and a population of about 147,000. The City’s current source of water is Lake Springfield that was constructed in the 1930s. The lake serves as the water source for its potable drinking water supply. As a result of drought conditions in 1953-1955, the City constructed a movable low head dam across the South Fork of the Sangamon River to supplement the Lake Springfield water supply during low lake levels.

2. What is NEPA?

The National Environmental Policy Act (NEPA) is a federal law that requires the identification and analysis of potential environmental effects of federal permitted actions. NEPA requires federal agencies utilize a systematic and interdisciplinary process to arrive federal decision-making. The NEPA process requires an analysis of environmental impacts associated project alternatives in support of that decision-making.

As part of NEPA, the public is informed and its concerns considered during the decision-making process. More information on NEPA is available on the Council on Environmental Quality’s NEPA website at:

3. Who is the Lead Federal Agency for this Project?

The United States Army Corps of Engineers (USACE) is the Lead federal agency for this project. “Lead agency” means the agency or agencies preparing or having taken primary responsibility for preparing the environmental impact statement.

4. Why is the United States Army Corps of Engineers Involved in the Project?

As the lead federal agency the USACE is responsible for development of the SEIS in support of their decision-making on issuance of a Section 404 permit under the Clean Water Act. The SEIS will support any required permitting by USACE for the selected alternative.

5. Why is a Supplemental Environmental Impact Statement (SEIS) required?

A Final Environmental Impact Statement (EIS) was prepared and published in November 2000 in which the Hunter Lake Reservoir was identified as the preferred alternative. Due to the length of time since the Final EIS was prepared, the USACE determined that a SEIS is needed to update the assessment of project alternatives and expand and update environmental studies.

The USACE identified areas in the original EIS where information should be updated, such as the water demand analysis, threatened and endangered species review, surveys for federally listed bat species, wetland delineations, cultural resources programmatic agreement, water quality analysis, and mitigation plans.

6. What is the Proposed Project and its Purpose?

The City is seeking to develop a supplemental water supply for municipal, commercial, and industrial customers to address concerns over the adequacy of its water supply. Based on an analysis of Lake Springfield’s storage and capacity, the Illinois State Water Survey had determined that it is an inadequate water supply system with a 50 percent probability of not meeting expected water supply demands. Under conditions of reduced water availability, the City is at risk of not meeting demands for commercial and residential water use, for industrial water supply, and for providing supplemental water for adjacent communities.

A recent study by the University of Illinois at Springfield concluded that there is an unmet demand of 12,773 acres for aquatic recreation activities within the 50+ mile radius of Springfield to the year 2035. The City wishes to meet a portion of the unmet demand for aquatic recreation activities to meet current and future demands to the year 2035. The City of Springfield desires to construct a multi-use reservoir encompassing approximately 2,650 acres in surface area. The reservoir will have a minimum yield of 12 million gallons per day (MGD) to meet water supply demands under drought conditions and a minimum of 2,500 acres of flat water area available to recreation to partially address the unmet water-based recreational demand in the Springfield area.

Other incidental benefits of an increased water supply and aquatic recreation include providing support for regional economic development.

7. How Often Does the City Experience Droughts?

Within the last 30 years, the City has experienced 3 droughts (1988, 2000, and 2012) which have led to mandatory water use restrictions. The drought of record from the 1950s lasted two years.

8. What Alternatives Were Considered?

A range of alternatives had previously been considered for the proposed project. While the 2000 EIS had previously identified the Hunter Lake alternative as the preferred alternative, the SEIS undertook an updated analysis of alternatives using current information. The SEIS reviewed all alternatives previously assessed in the 2000 EIS and will include an analysis of reasonable alternatives consisting of the following:

  • No Action alternative
  • Development of a new water supply reservoir that also supplies aquatic recreation opportunities
  • Development of groundwater well systems with associated pump stations and pipelines combined with surface water reservoirs that supply aquatic recreation opportunities.
  • Use of other existing surface water reservoirs and aquatic recreation opportunities.
  • Dredging of Lake Springfield for additional water supply and additional aquatic recreation opportunities.

Conservation measures apply to all alternatives, including the No Action alternative.

See Appendix D - Description of Eliminated Alternatives August 2023 for details.

9. What about Water Conservation?

To help balance water supply and demands, the City has been undertaking water conservation measures to reduce water use and/or water loss. The City conducts water conservation outreach activities through its Energy Services Office. The City provides rebates on high efficiency toilets and washers and offers water conservation kits, low flow showerheads, and low flow, water-efficient kitchen and bathroom faucet aerators. However, even with water conservation measures, the City anticipates a need for a supplemental water supply due to the potential of dry weather conditions and anticipated growth in water demand.

10. What is the City Doing to Reduce Water Loss by Leaks?

The City water distribution system consists of over 760 miles of water main. The City began leak detection surveys in 2008 and has surveyed over 2100 miles of water main to date. In 2022, 162 miles of water main were surveyed for leaks. The City views the Leak Detection Program as not only a water conservation practice but a necessity to provide reliable service to our customers. The City is committed to reducing water waste and will continue to perform annual leak detection surveys and plans to complete surveys of the entire distribution system every 4 years. The entire water distribution system has been surveyed for leaks almost three times since program inception.

11. Will the Project Meet Water Quality Standards?

In order to receive a permit under Section 404 of the Clean Water Act from the USACE, a Section 401 Water Quality Certification must also be obtained from the Illinois Environmental Protection Agency (IEPA). As part of the Section 401 Water Quality Certification process, the Project will need to demonstrate compliance with Water Quality Standards, such as levels of suspended solids, phosphorus, or other parameters. A study is underway to evaluate water quality concerns and identify if measures (watershed management initiatives and Project best management practices) are needed.

12. When will the SEIS be Completed?

The SEIS is anticipated to be completed the first quarter of 2024.

13. How can the Public and Other Interested Parties be Involved?

To promote open communication about the Project, the public and other interested parties can get involved and stay informed about the project by visiting this Project website periodically, attending public meetings, and providing comments and input during the SEIS development process.

The public is invited to submit comments on the Draft SEIS no later than September 25, 2023. An open house public meeting will be held on Wednesday, September 6th from 5:00 p.m. to 7:00 p.m. at the Lincoln Library, Springfield, Illinois. The Lincoln Library is located at 326 South 7th Street, Springfield, Illinois. This is to allow the public an opportunity to review information associated with the Draft SEIS as well as ask questions of resource specialists concerning the document. The open house public meeting will not include a formal presentation of the Draft SEIS. Individuals may provide written comments at the open house public meeting.

Written comments on the Draft SEIS and written comments to the public notice for the permit application, should be sent to: ATTN: Regulatory Division, U.S. Army Corps of Engineers, Rock Island District, Clock Tower Building, Post Office Box 2004, Rock Island, Illinois 61204-2004. Comments may also be submitted to Please indicate if you are commenting on the Draft SEIS, the permit application, or both. Email comments should have DEIS or Hunter Lake Permit in the subject line.

As an example, by going to the comment page, you can provide input to the Project Team. Formal comment periods also will occur as part of SEIS development, such as during the project scoping period and public review of the draft SEIS document.