The Minerals Management Service (MMS) developed a comprehensive strategy for postlease National Environmental Policy Act (NEPA) compliance for development and production projects in deepwater areas (water depths greater than 400 m (1,312 ft) in the Central Planning Area (CPA) and Western Planning Area (WPA) of the Gulf of Mexico (GOM). The strategy led to the development of a biologically-based grid system to ensure broad and systematic analysis of the GOM's deepwater region, which is explained on MMS's website. This strategy divides the deepwater Gulf into 17 areas or "grids" of biological similarity that generally correlate to water depth.