Combined sewer systems are no longer constructed. Today, separate systems are constructed for sanitary sewage and for stormwater.
Why We Have CSOs
Prior to 1983, when the City of Fairmont Wastewater Treatment was put in service, the combined sewer system discharged at various points along local rivers and streams. Along with the new wastewater treatment plant, “interceptor pipes” were installed along the waterways and the combined sewer system discharge pipes were connected to these interceptor pipes. Pumping stations were also installed to deliver the sewage to the treatment plant.
At various locations, CSOs were installed to discharge excess flow from rain events that could possibly flood the pumping stations, or exceed the treatment plant capacity.
Monitoring of CSOs
The City of Fairmont inspects its 43 CSOs at least once per month for dry weather overflows. Each CSO is also inspected after rainfall events.
If a dry weather overflow is detected, regulatory agencies are notified and corrective measures are undertaken as soon as possible. Typical causes of dry weather overflows are sewer line blockages and mechanical problems at pumping stations.
Inspection reports are prepared for all inspections and kept in a logbook. A copy of this logbook is maintained at the information counter on the 3rd floor of the J. Harper Meredith Building, 300 Jackson Street, for public review.
The City of Fairmont Program
The City of Fairmont continues to implement the Nine Minimum Controls as outlined by the United States Environmental Protection Agency. The nine minimum controls are:
- Proper Operation and Maintenance Program
- Maximization of Storage in the Collection System
- Review and Modification of Pretreatment Requirements
- Maximization of Flow to the Wastewater Treatment Plant
- Elimination of Dry Weather Overflows
- Control of Solids and Floatable Materials
- Pollution Prevention
- Public Notification
- Monitoring to Characterize CSO Impacts
The Nine Minimum Controls are considered a set of good housekeeping practices aimed at minimizing the frequency of CSO discharges at a minimal cost.
Public Notice of CSOs
Warning signs have been placed at and around CSO outfall locations. The signs indicate that a CSO overflow is nearby and the waters may be polluted during and immediately following rain events. The CSOs should only discharge during wet weather.