INFLOW/INFILTRATION REPAIR IN SOPE CREEK BASIN
Marietta Board of Water & Lights
When wet weather capacity issues plagued Marietta’s Sope Creek Basin, the Marietta Board of Lights & Water contracted Woolpert to help optimize sewer line operation and design the repair of significant inflow/infiltration (I/I) defects.
Woolpert’s plan called for a thorough review of past sewer system evaluation study (SSES) data to pinpoint and eliminate the largest sources of I/I. From existing reports, maps, field sketches and infrastructure data, Woolpert prioritized the sewer repairs based on their potential to remove I/I from the sewer system.
Woolpert performed the following additional tests to locate, assess and rank storm defects:
- Smoke testing
- Manhole inspections
- Dye flooding
- Closed-circuit television (CCTV) inspection
- Utility location
- Site photographs
- Data confirmation
- Under Woolpert’s guidance, city crews repaired the defects that contributed the highest amount of I/I. Woolpert also performed CCTV and heavy cleaning on a several lines identified as having large fat, oil and grease (FOG) deposits contributing to capacity problems. This cleaning occurred regularly until the source of the FOG was eliminated.
The project resulted in the reduction of over 700,000 gallons per day of peak I/I from the basin as well as the elimination of area sanitary sewer overflows. Woolpert partnered with Marietta in other priority basins on similar I/I identification and removal projects.