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PHMSA ID's Great Lakes as an Ecological Resource in NPMS

PHMSA recently updated its National Pipeline Mapping System (NPMS) by reclassifying the Great Lakes region as an unusually sensitive area (USA) ecological resource.  A USA is a subset of the high consequence areas hazardous liquid pipeline operators are required to identify as part of their integrity management programs.  Pipeline operators will now be able to use this GIS data to help with their integrity management planning, including determining whether a leak from their infrastructure could affect these ecological resource areas. 

The Great Lakes USA data includes Lake Ontario, Lake Erie, Lake Huron (including Lake St. Clair), Lake Michigan, and Lake Superior, and the connecting channels (Saint Mary’s River, Saint Clair River, Detroit River, Niagara River, and Saint Lawrence River to the Canadian Border).

For more information on the Great Lakes USA data, visit the NPMS website at:

Last updated: Monday, October 21, 2019