Inflow and Infiltration Evaluation of the City's Wastewater Collection System

As part of the City’s ongoing evaluation of the wastewater collection system, the Public Works Department will be conducting a “smoke test” on the sewer system in the eastern half of the City.  You are not required to be home when testing is being performed. All roads will remain open during all aspects of the testing.

The work will be performed by Flow Assessment Services, LLC of Goffstown, NH. Work hours on the project will typically be conducted Monday through Friday from 7:00 AM until 3:30 PM.  During testing, a non-toxic white smoke is introduced through the sanitary sewer system via a smoke generating machine. During this procedure, white smoke will be venting from manhole covers located on the street and plumbing vent pipes located on or near your roof surface. This is normal and should not be cause for alarm.

Smoke should not enter your premise unless there is a dry trap in your basement floor drain or in any seldom-used plumbing fixtures (e.g., mop sinks, laundry sinks, etc.).  You may wish to pour water down your basement floor drain or other plumbing fixtures to insure that the drain trap is full.  Smoke could also enter the building through defective plumbing.  The owner should take note of this because odors from the sewer system could possibly enter your building through the defective plumbing.

Should smoke be detected within the building, DO NOT BE ALARMED.  The smoke is NON-TOXIC AND NON-STAINING.  Simply ventilate the home and report the presence of smoke to Flow Assessment Services field crew.  If possible, they will assist you in locating the source of the smoke entering the building.

Flow Assessment Services, will have a representative on site during the smoke testing. Should you have any questions regarding the testing, you may contact Paul Casey, Project Representative at (603) 396-8690 or the Public Works Department at (603) 352-6550. 

A Public Meeting will be held at 7:00 PM on May 23, 2017 in the Auditorium at the Keene Public Library to answer any questions or concerns you may have regarding this planned work.  The work is scheduled to begin on June 12, 2017and is expected to last approximately five weeks. 

The City of Keene appreciates your patience and cooperation during this evaluation of the wastewater collection system.