Yale Campus Trumbull Street Area Sewer Separation Phase 2

Yale Campus Trumbull Street Area Sewer Separation Phase 2

As part of the implementation of the City of New Haven Long Term Control Plan, the second phase of the Yale Campus Trumbull Street Area Sewer Separation will include a combination of traditional gray infrastructure and green infrastructure.  This will reduce the flow of stormwater into the combined sewer system, allowing for more flow to reach the treatment plant and will reduce overflows to the Mill River.

Click link to learn more: Yale Trumbull St Sewer Separation Phase 2 Construction Notice

June 28, 2024 – 2 Week Schedule

2024 Pre-Lining Manhole Improvements

2024 Pre-Lining Manhole Improvements

This Project includes manhole improvements to facilitate the rehabilitation of approximately 5,600 feet of brick sanitary sewer pipes built prior to 1900 and ranging in size from 20”x30” to 48”. The manholes that require work are on Derby Ave (3 locations), Canner St (5 locations), Elm St (2 locations), and East St (1 location). Enclosed are a project map and individual location maps for general reference. This work prepares access for the Cured-in-Place Pipe (CIPP) lining project scheduled for to begin in June.

Click link to learn more: Project SSR 2024-04 Pre-Lining Manhole Improvements

GNHWPCA Pipe Lining Program

GNHWPCA Pipe Lining Program

Cured in Place Pipe (CIPP) lining is a proven trenchless rehabilitation process used to repair existing pipelines. Benefits include:

  • pipes can be rehabilitated without digging up the existing pipe or disrupting roads, driveways, sidewalks or landscaping
  • lining is less expensive than replacing the pipe
  • it allows for increased sewer flow capacity
  • the process can be completed in one to three days


Notices will be provided to residences and establishments in advance of any sewer lining work on their street.  Notices will be provided by the GNHWPCA's contractor both 10 days prior to and 24 hours prior to the conduct of the expected work.  Click the links on the right to see a sample of the 10-day and 24-hour notices.

The lining process involves installing a resin-saturated felt tube into an existing sewer pipe, that is inflated and hardened to create a new plastic pipe within the old pipe. During the process, a steam cloud coming from a vent stack at a manhole may be visible and occasionally there may be a "glue like" odor (styrene) during the curing process that will dissipate quickly when the process is complete.  To prevent odors from entering your home, all residents that receive a notice should pour ½ gallon of water into all plumbing fixtures and floor drains, especially those in basements where they are not used on a regular basis. See attached link on the right "Styrene Odor Information Document" for more information on how to keep sewer gas and other vapors out of your home or building.

Prior to lining the existing sewer, crews clean the pipe using high pressure water hoses and video cameras to inspect the pipe condition. They may also conduct dye testing to confirm connections between buildings and sewers. As such, residents may see activities related to the sewer relining for several weeks leading up to the actual lining.


Orchard Street Area Sewer Seperation

Orchard Street Area Sewer Separation

As part of the implementation of the City of New Haven Long Term Control Plan, storm drains in the Kensington Street area will be extended south along Orchard Street to connect to piping in The Rev. Dr. Martin Luther King Jr. Boulevard.  This project is being coordinated with improvements being constructed at the St. Raphael Campus of Yale New Haven Hospital in order to minimize disruption to the neighborhoods.

Click link to learn more: Orchard Street Area Sewer Separation Project Construction Notice

Smoke Testing Alert

GNHWPCA Smoke Testing Alert

Project SSR 2022-04: Westville-Whalley Sewer Study Smoke Testing

Project Area: New Haven-Westville Area: Along Whalley Ave, Fountain St, Valley St and connecting streets from Emerson St to W. Rock Ave (WARDS 25,27)

This project consists of conducting investigative analysis in the Westville area to identify potential source of extraneous water that discharge into the sanitary sewer system. This will include blowing white smoke into the sanitary sewer lines in the street and observing/recording where the smoke leaks out. This will help identify cost effective measures that the GNHWPCA, the City, the CTDOT, and the Community can take to help mitigate and manage exisiting and climate related increases in stormwater flows into the sanitary system.

For more information, including location map and sample door notice, click the Smoke Testing Links in the box to the right.


Testing Start: Late March 2023

Duration: Four (4) Days of Testing

Schedule: Mon-Fri from 8 am to 5 pm


GNHWPCA Large Diameter Pipe Cleaning Program

GNHWPCA Large Diameter Pipe Cleaning Program

GNHWPCA’s large diameter sewer pipes range from 30 inches in diameter to 84 inches in diameter. Most of these large diameter sewer pipes are main interceptor sewers located in the City of New Haven that transport combined flow to the ESWPAF for treatment. Periodic cleaning of these interceptor sewers is required to remove sand, grit, rocks, and other heavy debris that can accumulate in the pipe over time.Work crews clean the pipe using high pressure water hoses, cleaning heads and vacuums to extract the debris. Video cameras are also used to inspect the pipe prior to and post cleaning of the sewer pipes. As such, residents may see activities related to the large diameter pipe inspections for several weeks leading up to the actual cleaning of the pipes.

Click this Large Diameter Sewer Cleaning Projects link to view locations where large diameter pipe cleaning projects are being implemented and when.

Infiltration & Inflow Reduction: East Haven & Hamden

Infiltration & Inflow Reduction: East Haven & Hamden

This project involves investigating and rehabilitating existing pipes and manholes on Middle Thorpe Dr and Upper Thorpe Dr Areas. The rehabilitation will be done using trenchless technologies to minimize impacts on the neighborhoods and traveling public.

Click link to learn more: Hamden/East Haven Rehabilitation Project Construction Notice