This story was updated at 3pm on January 20th. We received information from the City of New York regarding their review of the expansion of the Algonquin Pipeline, and its potential impact on the Catskill Aqueduct.


A natural gas pipeline, which crosses over a major New York City drinking water aqueduct, will be increased in size as part of a multi-state pipeline expansion and replacement project. The “Algonquin Incremental Market Project” is currently under review by federal and state regulators.

The expansion of the Algonquin Pipeline within the Lower Hudson River Valley has attracted attention for several reasons, including the possibility that a new section of the pipeline will enter the grounds of the Indian Point nuclear power facility.

A final environmental review of the four-state pipeline project is expected to be released this week by the Federal Energy Regulatory Commission. A local group claims they have collected over 26,000 signatures requesting that federal regulators deny approval for the Algonquin project.

Crossing Paths with a NYC Water Tunnel

The Algonquin Pipeline, which delivers gas to Southern New England, crosses over the Catskill Aqueduct near Cortlandt, New York.

The 91-mile long Catskill Aqueduct supplies approximately 40 percent of New York City’s drinking water. The aqueduct runs from the Ashokan Reservoir in the Catskill Mountains, down to a large reservoir in Westchester, and terminates at the Hillview Reservoir in Yonkers.

Hillview then feeds City Tunnels 1 and 2, which bring water into New York City.

The Algonquin’s operator, Texas-based Spectra Energy, is seeking to replace the 26-inch pipeline crossing above the Aqueduct with one that is 42-inches in diameter.

According to federal regulators, “as with the existing pipeline, the new pipeline would be located above the aqueduct and would rest on concrete pads to provide adequate separation and protection for the aqueduct pipe.”

Gas Infrastructure Continues to Expand

High-volume hydraulic fracturing was recently banned in New York State, but expansion of the state’s gas pipeline network continues. Natural gas entering New York is being extracted in a number of western and Gulf Coast states, and, to a growing degree, in the Marcellus Shale region.

According to Spectra, the purpose of the Algonquin project is to expand its existing pipeline system from an interconnection at Ramapo, New York in order to deliver up to 342,000 dekatherms of gas per day to consumers in Connecticut, Rhode Island, and Massachusetts.

Roughly 2,600 “average size” homes could be heated for one year with 342,000 dekatherms of gas.

The work proposed for the Algonquin is an extensive upgrade which anticipates growing demand for natural gas across Southern New England. Supply bottlenecks in New York State are contributing to “price volatility” across the region say pipeline developers.

Spectra plans to replace 26.3 miles of existing pipeline; 11.3 miles of new pipeline will also be constructed.

Six existing gas compressor stations in New York, Connecticut, and Rhode Island will be upgraded to add more horsepower. Twenty-four meter and regulating stations will be upgraded, and three more M & R stations will be constructed.

Spectra Energy also recently completed a natural gas pipeline from New Jersey to Staten Island and Manhattan.

Questions from Local Government

But as gas infrastructure expands, local residents and government seem more inclined to proceed with caution.

The Westchester, Putnam and Rockland county legislatures have all passed resolutions calling for more information about the environmental and public health impacts of the Algonquin expansion project, and more oversight. For instance, the Rockland County legislature passed a resolution in September stating that:

1.) before permits are issued, an independent air emissions baseline assessment be conducted in the areas directly impacted by the proposed compressor and metering and regulating stations modifications;

2) the pipeline be continually monitored by an independent expert acceptable to industry, local government officials, advocates and the public, funded by Spectra Energy; and

3) results of the continuous monitoring of air, water, land and all other environmental impacts be reported daily to the New York State Department of Environmental Conservation and the EPA, and made available to the public in a transparent manner.

 Feds Issue a Tentative Green Light

In September, the FERC released a draft environmental review of the Algonquin project.

Regulators found that “construction and operation of the Project could result in numerous impacts on the environment.” Wildlife and their habitats would be affected, said FERC, as would 24 acres of New York wetlands and fisheries of “special concern.”

Nonetheless, the agency found that “most impacts would be reduced to less-than-significant levels.”

The New York portion of the Algonquin expansion project crosses 39 waterbodies, including the Hudson River. Those waterbodies are located within 8 “sub-basin” watersheds in Rockland, Westchester and Putnam Counties.

FERC noted in its review that it had received questions from the public about the pipeline’s proximity to the Indian Point nuclear power facility in Westchester County. A new section of the pipeline will run under the Hudson River from Rockland County and reportedly cross Indian Point’s property about a quarter-mile south of the reactors.

Spectra has told FERC that “because of the distance of the proposed project from…[Indian Point] and the avoidance and mitigation measures that it would implement, the proposed route would not pose any new safety hazards” to the power plant.

In November, LoHud reported that the Nuclear Regulatory Commission concluded that the new pipeline crossing Indian Point’s property “will not add significant risks to the safety of the reactors.”

The NRC’s reassurance that a possible pipeline accident on the grounds of Indian Point -such as an explosion- would not be a safety hazard drew criticism.

“It just defies logic,” given the size of the potential impact zone, Westchester Legislator Peter Harckham told LoHud.

Map of New York City's water supply system. Courtesy of NYC Department of Environmental Protection.
Map of New York City’s water supply system. Courtesy of NYC Department of Environmental Protection.

Protecting NYC’s Watersheds & Water Supply Infrastructure

Similarly, federal regulators are saying that “protection measures” implemented by Spectra will ensure that construction and operation of the Algonquin project will not result in “significant impacts” on New York City’s surface water resources.

The Croton, Catskill, and Delaware water supply systems together deliver roughly a billion gallons of water every day to almost half of the state’s population. The Catskill and Delaware systems are located about 50 miles north and northwest of the Algonquin project facilities. However, expansion work on two sections of Algonquin pipeline will take place within the Croton watershed, closer to New York City.

How does Spectra plan to protect the watershed as it carries out pipeline construction?

The company says it has specialized procedures for potential issues like erosion and sediment control, spill prevention and mitigation, “unexpected contamination encounters,” and stormwater management.

The prospect of widening the Algonquin Pipeline as it runs over the Catskill aqueduct seems to have attracted more focused attention from FERC. Federal regulators ordered Spectra to consult with the New York City Department of Environmental Protection to develop a final crossing plan for the Catskill Aqueduct.

“Algonquin should file with the [FERC] Secretary a site-specific crossing plan for the Catskill Aqueduct developed in consultation with the NYC DEP,” wrote FERC’s reviewers.

“At a minimum, the plan should include the location of the proposed pipeline relative to the aqueduct, the proposed construction methods, the timing of construction, any mitigation measures that would be implemented to minimize impacts on the aqueduct, and documentation of consultation with the NYC DEP,” FERC stated in its draft review.

Has Spectra followed through on FERC’s order?

Adam Bosch, Director of Public Affairs for the DEP’s Bureau of Water Supply, told NYER that Spectra “has submitted some preliminary design drawings to DEP, which are currently under review to ensure their proposal for a larger pipe would not pose a threat to our infrastructure or impede our access for regular maintenance to the Catskill Aqueduct.”

“At this point we’re unable to say when our review of their preliminary design would be complete, or if we’re going to require any changes to what they’ve presented,” Bosch concluded.

 Public Hearings this Week

In addition to a final federal approval, the Algonquin project also requires specific permits and approvals from the state’s Department of Environmental Conservation. These include Air Title V permits for the proposed compressor station upgrades, as well as a Water Quality Certification, Stream Disturbance and Freshwater Wetlands permits for portions of the pipeline upgrades.

The DEC has extended the public comment period through February 27th on these applications and draft permits. Comments can be submitted to DEC Project Manager Michael Higgins at

State DEC hearings on the project will be held in Brewster this Wednesday, January 21st, at 6 p.m. Location: Henry H. Wells Middle School Auditorium, 570 Route 312.

And in Stony Point on Thursday, January 22nd, at 6 p.m. Location: Stony Point Community Center, 5 Clubhouse Lane.

The state DEC is also reviewing a separate pipeline that will cut through Broome, Chenango, Delaware, and Schoharie counties. The contested 124-mile Constitution pipeline will ferry natural gas directly from the Marcellus Shale fields in Pennsylvania to New York and, ultimately, other Northeast states.

The Constitution Pipeline was approved by the Federal Energy Regulatory Commission in December and now awaits final approval from New York State.