reports calcium from milk spilled into Jerome, Idaho’s city sewer system has shut down the facility for six weeks, turning a canal system into a sewer.

Calcium from the milk spilled into the city sewer system on Dec. 30 clogging filter membranes. It has taken six weeks to strip the membranes of the calcium buildup and the city plans to have wastewater treatment under control this week.

The North Side Canal system has absorbed excess sewer buildup while the treatment facility was shut down. The city received approval from the U.S. Environmental Protection Agency to run treated wastewater down the canal, eventually discharging into the Snake River.

The city sent chlorine wash down the canals on Tuesday and plans to send treated wastewater through the canals, but it won’t be enough to clean up six weeks of contamination.

The city will work with the EPA. The canal’s must be clean before the canal water will be turned on in March.