Support for Protecting U.S. Water Resources under the Clean Water Act

Since 2011, PG Environmental (a division of ERG) has supported the U.S. Environmental Protection Agency in protecting our nation’s water resources, including rivers, streams, and wetlands, under the Clean Water Act. Much of this support has focused on Waters of the United States as defined in CWA regulations (WOTUS) and implementation of CWA Section 404, which regulates the discharge of dredge or fill material into WOTUS. Our work has involved:

• Conducting desktop geospatial and modeling analyses to determine impacts to waters. Analyses have involved developing analytical workflows utilizing high-level aerial photography, topography, LIDAR, and vector data to model flow accumulation and pathways using ArcGIS and Google Earth tools.
• Compiling the data and information EPA needs to target stream crossings for inspection.
• Supporting inspections of dredge-and-fill impacts to wetlands.
• Performing field assessments to determine the discharge of oil and hazardous substances to WOTUS.
• Evaluating the physical, chemical, and biological indicators of water bodies or conveyance channels to determine jurisdictional status, including vegetation and soil characterization and assessment of hydro-geomorphic conditions in a variety of environments.
• Performing technical reviews of prior site evaluations to evaluate accuracy.
• Developing technical reports and publication-quality map products for EPA’s use in determining impacts to WOTUS.

In addition, PG has supported WOTUS and 404 enforcement cases in Alabama, Alaska, Arkansas, California, Florida, Hawaii, Indiana, Illinois, Louisiana, Mississippi, Montana, Nevada, New York, North Dakota, Ohio, South Carolina, South Dakota, and Texas. In one example, we helped EPA evaluate a 410-mile-long oil and gas pipeline by assessing over 100 wetland and stream crossings.