Atlantic Sunrise natural gas pipeline is an expansion of the existing Transcontinental (Transco) pipeline, the biggest gas pipeline system by volume in the US.
The $3bn expansion project involved the construction of the approximately 300km-long Central Penn Line (CPL) in Pennsylvania, which is jointly owned by Transco and Meade Pipeline.
Transco is an indirect subsidiary of US-based energy infrastructure company Williams Partners and operates more than 10,000-mile pipeline network in the US.
Meade Pipeline is a joint venture of WGL Midstream (55%), Cabot Oil and Gas (20%) and EIF Vega Midstream (25%).
Construction on the Atlantic Sunrise natural gas pipeline started in September 2017 and was completed in September 2018. The pipeline was placed in service in October 2018 and will supply up to 1.7 billion cubic feet per day (bcf/d) of Marcellus Shale gas from the north-east Pennsylvania to gas markets in south-eastern Pennsylvania as well as Mid-Atlantic and southeastern US.
The Atlantic Sunrise pipeline has increased the design capacity of Transco pipeline system to 15.8bcf/d.
Atlantic Sunrise natural gas pipeline design and route details
The Atlantic Sunrise natural gas pipeline project included the construction of two segments of new pipeline called new Central Penn Line (CPL) totaling approximately 300km, two pipeline loops totaling 18km, 4km of pipeline replacement, two new compressor stations, and compressor station modifications in five states.
The Central Penn Line (CPL) comprises the 94.5km-long CPL North segment and the 205km-long CPL South segment.
CPL North is a 30in-diameter pipeline that originates near the existing Transco Leidy Line in Columbia County and connects to the new Zick Meter Station in Susquehanna County.
The 42in-diameter CPL South pipeline originates at the existing Transco Mainline system in Lancaster County and ends at a milepost for Transco Leidy Line in Columbia County.
The maximum allowable operating pressure (MAOP) of both CPL North and CPL South is 1,408psig (pounds per square inch gauge).
The project also included 4km-long and 36in-diameter of pipe looping (Chapman loop) that connects two mileposts of the Transco Leidy Line in the Clinton County and the 14km-long and 42in-diameter Unity loop joining two mileposts of the Transco Leidy Line in Lycoming County.
Further, total 4km segments of Transco’s Mainline A and Mainline B were replaced in the Prince William County, Virginia, for the Atlantic Sunrise pipeline project.
Atlantic Sunrise pipeline infrastructure and facilities
Two new compressor stations have been built in Columbia and Wyoming Counties, as part of the project.
The new compressor station (No.610) in Orange Township in Columbia County consists of two 20,000 horsepower (hp) compressor units, whereas the new compressor station (No.605) in Clinton Township in Wyoming County houses two 15,000hp compressor units.
Electricity for the compressor stations is supplied through two new 69kV transmission lines with a total length of 10km from nearby substations.
Five new metering stations named Zick, Springville, North Diamond, West Diamond and River Road were built as part of the project.
The project also involved replacement of gas turbines and compressor generators at three existing compressor stations in Lycoming, Columbia and Howard counties, as well as towers replacement at several other existing compressor stations along the route.
Central Penn Line (CPL) ownership and investment details
The CPL South pipeline is 70.59% owned by Transco and 29.41% by Meade Pipeline, while the CPL North is 41.18 % owned by Transco and 58.82% by Meade.
Meade’s investment on the Central Penn Line is estimated to be $746m. WGL Midstream, being the majority (55%) share holder of Meade, invested $410m in the pipeline project.
The remaining investment came from Transco.
Gas purchase agreements for Atlantic Sunrise project
Transco entered 15-year shipping agreements with nine companies for approximately 1.7bcf/d of natural gas from the Atlantic Sunrise pipeline project in February 2014.
The shippers for the project include Cabot Oil & Gas (850Mcf/d), Chief Oil & Gas (420Mcf/d), Seneca Resources (189Mcf/d), Southern Company Services (60Mcf/d), Anadarko Energy (44Mcf/d), Southwestern Energy Services (44Mcf/d), WGL Midstream (44Mcf/d), Inflection Energy (26Mcf/d) and MMGS (22Mcf/d).
The U.S. Army Corps of Engineers carried out the environmental impact study for the Atlantic Sunrise pipeline project.
The pipeline installation was performed by four primary construction contractors including Henkels & McCoy, Latex Construction Company, Michels Corporation, and Welded Construction.
The new 605 compressor station for the pipeline in Wyoming County was constructed by VEC, whereas the construction contractor for the new 610 compressor station in Columbia County was LMC Industrial Contractors.
PPL Electric Utilities was responsible for the electrification work for supplying electricity to the new compressor stations of the pipeline project.
Transco natural gas pipeline details
The Transco pipeline system, exceeding 10,000 miles of total pipe length, accounts for approximately 10% of the US gas supply.
The pipeline originates from South Texas and passes through 13 states including Maryland, Philadelphia, Trenton, New Jersey, Allentown, Hazelton, and Washington D.C to extend till the New York City.
The Transco natural gas pipeline has more than 50 compressor stations along its route.