Missouri Public Service Commission

JEFFERSON CITY---The Missouri Public Service Commission has approved an agreement filed by Missouri-American Water Company (MAWC), the Public Service Commission Staff and the Office of the Public Counsel which will adjust the Water and Sewer Infrastructure Rate Adjustment (WSIRA) on MAWC customer bills. The Office of the Public Counsel is a separate state agency that represents the general public in matters before the Public Service Commission.

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.

In this case, MAWC sought to recover WSIRA qualifying infrastructure replacement costs incurred during the period of May 1, 2022 through July 31, 2022. These costs are not currently reflected in customer bills.

Residential St. Louis County water customers of MAWC currently pay a monthly WSIRA of approximately $0.94 per 1,000 gallons. Under the agreement, the monthly WSIRA will increase to approximately $1.27 per 1,000 gallons of water. MAWC residential water customers outside of St. Louis County currently pay a monthly WSIRA of approximately $0.47 per 1,000 gallons. Under the agreement, the monthly WSIRA will increase to approximately $0.70 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 currently pay a monthly WSIRA that is 0.8991% of the total monthly sewer bill. Under the agreement, that will drop to 0.8821% of the total monthly sewer bill. For all other MAWC residential sewer customers, the current monthly WSIRA will go from 5.5519% of the total monthly sewer bill to 5.6572% of the total monthly sewer bill.

Changes to the WSIRA are expected to take effect in mid-January.

MAWC provides water service to approximately 474,000 customers in Missouri. It also provides sewer service to approximately 16,500 customers in the state.

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Case No. WO-2023-0008