Collection System Operation and Maintenance

On a dry day, Lowell’s collection system conveys an average 23 million gallons (or more than 200 million pounds) of used water and waste to the Duck Island treatment facility for reclamation. This causes a lot of wear-and-tear, and our maintenance staff of mechanics, electricians and inspectors works every day to survey and perform preventive maintenance to keep this system of pipes, manholes, pump stations, gates, interceptors and siphons working properly.
On a wet day, Lowell’s early roots in the industrial revolution become apparent – centuries-old drainage systems were designed to combine stormwater and sewage for conveyance directly to the river without treatment. Federal funding for the Clean Water Act was not sufficient to separate stormwater flows from sewage in old cities such as Lowell, so large amounts of stormwater entering the collection system often drive flow rates of greater than 100 million gallons a day during rain events.
Through modern, automated control systems, much of this flow is stored and treated later. On some days, the rain is simply too much, and in order to prevent damage to the collection system, to resident’s properties, and widespread street-flooding, relief points known as combined sewer overflow (CSO) diversion stations discharge to the river. Learn more about our CSO control and High-Flow Management programs here.

Collection system maintenance activities include:

  • Catch basin cleaning to remove sediments and associated contaminants
  • Video inspection of sewer system lines to identify maintenance needs
  • Sewer line rehabilitation and replacement
  • Catch basin and manhole repair and replacement
  • Infiltration studies to help keep groundwater and river water from entering the system
  • Intermunicipal metering and billing measures flows received from our co-permittees in Dracut, Chelmsford, Tyngsborough and Tewksbury and helps to generate revenue for our operations, maintenance and reinvestment (capital improvement) projects