The canal was constructed in the early 1860s as a means of improving industrial commerce in southwest Brooklyn. The NYCDEP said that the proposed upgrade of the Gowanus Canal flushing tunnel system and wastewater pumping station are both vitally important in the effort to improve the water quality in the Gowanus Canal over the long term. Currently the canal is listed as impaired.
Degraw and Columbia Streets site trenchless works, recommending microtunnelling, is one section of the large rehabilitation project.
The construction of the proposed action at the Degraw and Columbia Streets site would take approximately two years and four months beginning in February 2010, which includes the expected duration of lane or partial street closures. The Gowanus Canal flushing tunnel system exit chamber in Degraw Street near the intersection with Columbia Street would be under subsurface construction for nine months starting in February 2010. November 2010 through May 2012 would be scheduled for the subsurface installation of the 33 inch diameter wastewater force main within the Gowanus Canal flushing tunnel, the construction of the clean out and dissipation chambers, microtunnelling, and the construction of the gravity sewer would be scheduled to begin May 2010 and continue February 2011.
