Storm Water / I & I
Four recent reports regarding the impact of storm water and other factors on the City’s sanitary sewer system are now available for public review through this website.
The reports deal with storm water inflow and infiltration (I and I) into the sewer system, possible sewage overflows and equipment failures, any of which can cause environmental and health threats.
Two of the reports deal directly with I and I. The City’s Assessment and Reduction Plan develops steps to identify sources of I and I and reduce them throughout the City’s 48 miles of sanitary sewer. When storm water enters the sanitary sewer through cracks or breaks, it can cause raw sewage to discharge from the mains and overwhelm the sewer treatment plant. The separate Inflow and Infiltration Report establishes an Action Plan to report and respond to any emergency while maintaining critical plant operation and employee safety. The Plan states that 23 drainage basins encompassing 3,200 acres contribute storm water flow to the City’s sewage treatment plant. The City also maintains 14 pump stations to bring waste to the treatment plant, and these must be kept in good working order and be able to cope with power outages during storms.
The third report is called the Sanitary Sewer Inspection and Maintenance Program which deals with procedures to prevent sanitary sewer overflows which can release untreated sewage to surface waters. The report notes that overflows can be caused by pipe or equipment failure, poor maintenance, undersized pumps, aging infrastructure, community growth or I and I. Regular maintenance will reduce incidents and better manage system performance. The report suggests that the City adopt a Capital Improvement Program to replace aging components and provide for system expansion so the City can be prepared financially to address replacement and maintenance issues as they emerge.
The final report outlines what to do in the event of a spill. The Sewer Overflow Response Plan calls for quick action to minimize risk to public health and safety if raw sewage is released. It stresses the importance of quickly notifying the public of any danger and concludes that proper maintenance can significantly reduce the likelihood of sewer overflows.