Missouri Public Service Commission

JEFFERSON CITY---To reflect Water and Sewer Infrastructure Rate Adjustment (WSIRA) qualifying replacement costs incurred during the period of January 1, 2023 through October 31, 2023, the Missouri-American Water Company (MAWC) will be adjusting the WSIRA charge on customer bills. These costs are not currently reflected in customer bills. MAWC sought the adjustment in a filing with the Public Service Commission on September 1, 2023.

State statutes provide eligible water and sewer corporations with the ability to recover certain eligible infrastructure system replacement costs without the need to file a formal rate case with the Public Service Commission. These investments in infrastructure are recovered through a WSIRA.

Residential St. Louis County water customers of MAWC will pay a monthly WSIRA of approximately $0.70 per 1,000 gallons. MAWC residential water customers outside of St. Louis County will pay a monthly WSIRA of approximately $0.32 per 1,000 gallons. For sewer customers, the WSIRA is based on a percentage of the total monthly sewer bill. Arnold residential sewer customers of MAWC will pay a monthly WSIRA that is 0.1269% of the total monthly sewer bill. All other MAWC residential sewer customers will pay a monthly WSIRA that is 0.7585% of the total monthly sewer bill.

Changes to the WSIRA rates will take effect on January 20, 2024.

MAWC provides water service to approximately 482,000 customers in Missouri. It also provides sewer service to approximately 23,000 customers in the state.

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Case No. WO-2023-0427