N.Y. denies water permit to Williams Northeast Supply pipeline

April 20 (Reuters) - New York environmental regulators on Friday denied a water permit for Williams Cos Inc's proposed Northeast Supply Enhancement natural gas pipeline project, another blow to the company's hopes of expanding gas service into New York:

* The denial for the $1 billion project is reminiscent of the state's denial of water quality certification for Williams' proposed Constitution gas pipeline in 2016. Williams is still fighting that denial in court and at the regulatory level.

* The New York Department of Environmental Conservation (DEC (Shanghai: 600875.SS - news) ) said Williams has not completed its application in a timely manner and the environmental review being conducted by the U.S. Federal Energy Regulatory Commission (FERC) remains incomplete.

* FERC issued a draft environmental impact statement on March 23 concluding that environmental impacts from the Northeast Supply Enhancement project would be reduced to "less than significant levels" with the implementation of mitigation measures proposed by the company and FERC.

* New York's DEC, however, said the application materials submitted showed "potentially significant environmental impacts that raised serious concerns."

* In response to the denial, Williams said it "fully intends to resubmit the project's application so that the agency can continue its permit evaluation and provide the clearances necessary to construct this critical piece of pipeline infrastructure."

* The Northeast Supply Enhancement project is designed to expand Williams' existing Transco pipeline to increase gas deliveries to New York City by up to 400 million cubic feet per day (mmcfd), enough to fuel about 2.3 million homes.

* National Grid Plc (LSE: NG.L - news) , the biggest distributor of gas in the U.S. Northeast, agreed to transport fuel on the project.

* Williams said it could start construction in early 2019 and complete the project in time for the 2019/2020 winter heating season if it gets the approvals needed.

* The project includes the addition of about 37 miles (60 kilometers) of pipeline and compression to the existing Transco system in Pennsylvania, New Jersey and New York. Most of the new pipe, about 23.5 miles, would be offshore in the New York Bay.

* The Transco mainline runs 1,800 miles between Texas and New York City.

* Williams filed with FERC for permission to build the pipe, known as a certificate of public convenience and necessity, in March 2017.

* The 125-mile Constitution pipeline was designed to transport 650 mmcfd of gas from Pennsylvania to Upstate New York. (Reporting by Scott DiSavino Editing by Leslie Adler)