08/05/2026
Update - Madison Metropolitan Sewerage District (MMSD) Force Main Pipe Leak
The Lake Waubesa Conservation Association (LWCA) and the Madison Metropolitan Sewerage District (MMSD) are providing this update to keep members and neighbors informed about the August 22, 2025 force main pipe failure near the Nine Springs Wastewater Treatment Plant and the actions taken since the incident.
Timeline of Events:
August 22, 2025 - A break occurred in the Pumping Station 2 force main located along the Capital City State Trail near the Nine Springs Wastewater Treatment Plant.
August 23, 2025 - MMSD completed a temporary repair of the damaged pipe joint and restored normal operations.
August 28, 2025 - Water quality monitoring showed three consecutive days of safe E. coli levels.
Test results were below 1,000 MPN/L, the Wisconsin standard used for beach closures.
October 6, 2025 - MMSD completed a permanent repair of the damaged section of pipe.
Investigation and Follow-Up Actions:
To better understand why the pipe deteriorated prematurely, MMSD initiated a comprehensive investigation examining pipe condition, soil chemistry, groundwater conditions, and other factors that may have contributed to the failure.
Actions completed include:
A pipe sample was sent to the Ductile Iron Pipe Research Association for specialized testing and analysis.
MMSD launched a $400,000 capital improvement project to assess the overall condition of the force main and identify any potential weaknesses.
Soil and groundwater samples were collected and analyzed from the repair site.
Additional testing was conducted by an independent third-party laboratory.
Looking Ahead - MMSD will use the results of these studies, along with engineering best practices, to guide future maintenance and infrastructure improvements and reduce the risk of similar failures.
Upcoming activities include: - Issuing a Request for Proposals (RFP) for a comprehensive condition assessment of the Pumping Station 2 force main.
Using the condition assessment results to inform future repair, rehabilitation, and replacement planning.
Ongoing Monitoring - While these investigations and assessments continue, MMSD is actively monitoring system flow rates and operational data to ensure there are no indications of additional leaks or failures.
LWCA will continue to work with MMSD and share significant updates with members as additional information becomes available.
