Five Year I/I Control Plan, Leicester, MA

Tata & Howard is working on a five year infiltration/inflow (I/I) control plan for Cherry Valley Sewer District (CVSD) in Leicester, Massachusetts. The program consists of flow monitoring, field investigation, and rehabilitation to the wastewater collection system.

In year one of the program, continuous flow, groundwater, and rainfall monitoring took place in the spring to collect data for program analysis.  Simultaneous to the monitoring, manhole inspections were performed to assess I/I potential from manholes.

Year two consisted of a data analysis of the flow monitoring results of year one. The results of this data analysis from the I/I control plan provided guidance to moving forward with I/I investigation.

Field investigation commenced in year three of the program with smoke testing being completed throughout the collection system. To follow up with results from the manhole inspection, manhole rehabilitation was performed on manholes in which I/I was evident.

Year four focused on field investigations. A large section of the collection system was inspected via closed circuit television (CCTV). Follow up building inspections were also performed in areas where sump pump connections were suspected to be an issue. Year four also focused on system operation and maintenance.  Documents were created for CVSD to focus on operations and maintenance of the system, and specifically for the manhole which houses the system flow meter into Worcester.

Year five is consisting of further CCTV investigation and a final report to summarize the project and provide recommendations on moving forward with investigations.  Future work is anticipated to focus around GIS aspects of the system and working with CVSD to maintain records and reduce I/I by being proactive with investigation and maintenance.