GEOLOGIC CHARACTERIZATION OF THE CHAMPLAIN HUDSON POWER EXPRESS

The Champlain Hudson Power Express (CHPE) is an ongoing energy investment project in New York State that plans to install a 1,000 megawatt high-voltage direct current (HVDC) power cable from the U.S.-Canada border to New York City for the purpose of delivering clean and renewable energy to the New York metropolitan area. The New York State Geological Survey (NYSGS), in cooperation with the project’s developer, Transmission Developers Incorporated (TDI), has provided the basis for a comprehensive geologic assessment of the overland portion of the proposed HVDC cable route, which extends for approximately 210 kilometers (~130 miles) in length. Previously existing surficial maps for 34 7¹/₂-minute USGS quadrangles at the scale 1:24,000 were compiled and digitized using a geographic information system (GIS), resulting in a seamless layout of the distribution of sedimentary deposits specific to areas along and adjacent to the proposed overland route. This cumulative map and subsequent fieldwork using hand augers, shovels and roadside exposures, indicate that the overland route is primarily covered with Pleistocene sediments deposited by melting glaciers following the last ice age, including glacial till and lacustrine sand, silts and clay from proglacial Lake Albany/Vermont. A geospatial database containing 8,400 discrete borehole data from various sources was constructed and has contributed extensive subsurface information allowing for the development of 2D and 3D isopach, structure and depth-to-bedrock maps. These peripheral materials, in congruence with a compilation of existing LiDAR and digital elevation models (DEM), have been used to analyze geomorphic features such as drumlins and valleys, and aid in the recognition of areas prone to geologic hazards, such as landslides and flooding, along the extent of the proposed HVDC power cable route. The net result is an unparalleled, modern geologic framework to guide the planning and decision making process associated with major infrastructure projects in New York State.