TOPEKA, Kan. (AP) — Crews in Topeka have been working to repair a sanitary sewer leak that resulted in 55,000 gallons of raw sewage spilling into the Kansas River.

It’s the city’s third sewage release into the Kansas River since April. Bob Sample, the city’s general manager of water pollution control, says the cause of the Tuesday leak hasn’t yet been determined.

About 3 million gallons of raw sewage discharged into the Kansas River in late April after a power failure at the city’s south Kansas River pump station.

Earlier this month, the city dealt with a surge of heavy rain by bypassing a secondary cleaning process and dumping as many as 50 million gallons of sewage into the river before it underwent a secondary cleaning process.