Gowanus Canal CAG Water Quality & Technical Committee Meeting

The Gowanus Canal Community Advisory Group’s Water Quality/Technical Committee will hold its October monthly meeting on Monday, October 5th, 2026 from 7:00 p.m. to 8:00 p.m., via Zoom video conference.

You can join the Zoom meeting here: https://us06web.zoom.us/j/9808972869?omn=88094846131

Meeting ID: 980 897 2869

1. Open Issues

a. Seal Gas line at Huntington and other NAPL leaks

b. TB 1 Request presentation of completed design and Reso regarding naming – Marylander Basin, Denton’s Mill.

c. Ingress/Egress

d. Mounding: We will follow up on the mounding studies – Has EPA done a new one? If so, present on it again. Issue is forward-looking – climate change.

2. Housekeeping

a. PowerHouse walkway at TB1. No update

b. DO Levels: Any acknowledgement from Fagel, Waldron or Smith to our resolution re: DO levels, Erica?  NOT YET – 8/3/2026 Erica followed up.

c. OMP: What is EPA’s demand for responsible parties to maintain an operation and maintenance plan (OMP) for the Gowanus Canal Clean-up strategy? Who will ensure that the OMP is done going forward? Will EPA continue to check that the water quality remains good and that the cap is intact? Does EPA have an OMP Plan? Where is it?  Will follow with Katia at next meeting.  Katia was not present.  We will follow up.

d. Hydrology – Aaron responded (see below) that DEC hopes to have the survey complete by 1^st Q 2027. Current hydraulic conditions, including groundwater elevations and flow direction. DEC study.  We know they are not including toxins in the study. 

Suggestion – overlay the map.  – Now that Jason has created a tool, can DEC use it once its survey is done?  Can we use it?  If DEC does not want to use our tool, can we layer their survey results into our map?  Jason shared with Aaron.

3. Review emails and responses so far and decide whether to send follow up questions on some

a. Real-time canal monitoring/public reporting – waiting on Court of Appeals. No action. Summary of decision below. Mike Dulong presented at General CAG 9/22/2026.

b. Bond-Lorraine Sewer – DEP Alicia West – Appears DEP will run the sewage from Smith to the canal northwards to the Pumping Station, while they run the storm water from that area south where it will be dumped into the canal at Public Place. Design planned to go to DDC by year’s end. 9/16 Joan sent questions to DEP – no response yet. Andrea said at the General CAG meeting that north-flowing CSO pipe will be (obviously) underground and will flow down, not uphill, and will not empty into the flushing tunnel. Awaiting DEP confirmation.

c. CSO’s – DEP Alicia West, EPA Victoria Sacks – We got an answer from DEP regarding its LTCP. See below for full answer but importantly there is no LTCP for the CSO tank results and re-dredging would only happen if EPA orders it.  At that point, DEP and other PRPs would be required to dredge.  There is no amount of sediment that would trigger a re-dredging, but there are other triggers.  Under EPA’s ROD, there are several recontamination limits based on environmental sediment quality that would be the trigger for maintenance dredging.  The most notable trigger is sediment exceeding 20 ppm of PAHs.  March 30, 2026, EPA notified the City of the completion of capping in RTA1. Under the terms of the 2021 UAO, the City will have one year from the date of that letter to begin in-canal sediment sampling.  The text of the letter is below.  We are awaiting a schedule from the City.

d. NAPL leaks and remediation at the head of the Canal – Joan followed up to obtain Victoria’s answers to our questions (below) that Tom Mongelli read out at the CAG meeting 7/27 (see below). It seems a lot of what is going on is based on suspicion of what is going on but is also exploratory if EPA has it wrong.  Work is in progress.  Victoria’s full response is below but at the 9/22 CAG meeting she indicated there is bulging at the bulkhead so they are re-evaluating the plan.

4:  Future or today?

a. Has DEP started to measure how much of first flush the new buildings are capturing?  We did not cover this yet.

b. Did the scientific projections in the LTCP account for the results of climate change?  We eventually will ask questions about this.

All Gowanus CAG meetings are open to the public, unless specifically noted otherwise.