Oct 16, 2020

Water Subcabinet Members Highlight Enhanced Aquatic Resource Mapping with Western States

EPA Press Office (press@epa.gov)  — Yesterday, as part of the Western States Water Council (WSWC) virtual Fall 2020 meeting, U.S. Environmental Protection Agency Assistant Administrator for Water David Ross highlighted ongoing cross-agency efforts to enhance the nation's aquatic resource maps. The federally-led mapping effort illustrates the enhanced interagency coordination established by the Trump Administration that will accelerate progress in developing better data, tools, and strategies for managing our nation's vital water resources, including developing maps of "waters of the United States" (WOTUS) that can more accurately depict the scope of federal Clean Water Act (CWA) jurisdiction.

"After nearly 50 years of implementing the Clean Water Act, it is disappointing that the federal government lacks the ability to point to a map and tell our stakeholders which waters are subject to federal jurisdiction, and which are exclusively reserved to the capable management of our state and tribal partners," said EPA Assistant Administrator for Water David Ross. "Because there are currently no maps showing the universe of waters regulated under the Clean Water Act, we are leveraging the collective expertise, tools, and resources of the Water Subcabinet to solve this problem."

Representatives from EPA, Department of the Interior (DOI), and Department of the Army (Army) along with Western State water managers and expert scientists from the EPA, U.S. Geological Survey (USGS), and U.S. Fish and Wildlife Service (USFWS) discussed the benefits of enhanced geospatial tools and novel approaches to improve the accuracy of maps depicting surface waters nationwide. When fully developed, maps of CWA jurisdiction will promote greater regulatory certainty, relieve some of the regulatory burden associated with determining the need for a CWA permit, and play an important part in helping to implement the goals and policies of the CWA.

Under the newly formed Water Subcabinet, established by the President's Executive Order "Modernizing America's Water Resource Management and Water Infrastructure," EPA and the Army are aligning their WOTUS mapping interests with DOI's established and ever-improving aquatic resource mapping efforts, including the National Hydrography Dataset (NHD), National Wetlands Inventory (NWI), and other datasets. At yesterday's WSWC Fall Meeting, technical experts from EPA, USGS, and USFWS described the ongoing cross-agency efforts to enhance the existing NHD and NWI frameworks, coupled with on-the-ground field research, streamflow monitoring, and geospatial modeling approaches to improve the accuracy of the nation's stream and wetland maps.

"In developing the new WOTUS definition under the new Navigable Waters Protection Rule, we heard from stakeholders that maps of jurisdictional waters could increase certainty and transparency regarding which waters are jurisdictional and which waters are not," said Principal Deputy Assistant Secretary of the Army for Civil Works Ryan Fisher. "This interagency mapping effort will increase certainty and efficiency within the Corps' regulatory programs while enhancing predictability for landowners and businesses to support the economy and accelerate critical infrastructure projects."

To help inform this effort, the Water Subcabinet is engaging with stakeholders like WSWC to make progress on these mapping goals, while being advised by a work group of participants from federal agencies with interest and expertise in geospatial mapping. EPA and the Army believe the most efficient way to address their CWA mapping needs is to better align their efforts with DOI's existing processes and national mapping capabilities.

"Department of the Interior's USGS, FWS, and other bureaus have a long history of working together to map the nation's waters," said DOI Assistant Secretary for Water and Science Timothy Petty. "Now, by focusing our assets and capabilities to the needs of USACE and EPA, our aim is to accelerate enhancements to our existing national frameworks and the maps they will support for a wide variety of federal, state, tribal, and private sector water programs. This is a prime example of the cross-agency work that the Water Subcabinet can tackle to better manage our nation's aquatic resources and leverage taxpayer dollars."

For more information on mapping jurisdictional waters under the CWA, please visit: https://www.epa.gov/sites/production/files/2020-01/documents/nwpr_fact_sheet_-_mapping.pdf

There are currently no comprehensive datasets through which EPA and the Army can map the universe of jurisdictional waters under the CWA. While the USGS National Hydrography Dataset (NHD) and the USFWS National Wetlands Inventory (NWI) are the most comprehensive hydrogeographic datasets mapping waters and wetlands in the United States and are useful resources for a wide variety of water management applications, they currently have technical limitations that present significant challenges for use as standalone tools to determine the full scope of CWA jurisdiction, regardless of the regulatory definition of WOTUS. In fact, prior to finalizing the now-rescinded 2015 rule defining WOTUS, an EPA blog post published under the previous administration entitled "Mapping the Truth" stated, "While these [USGS and USFWS] maps are useful tools for water resource managers, they cannot be used to determine Clean Water Act jurisdiction – now or ever." Due to limitations of the existing datasets, the Trump Administration agrees with Obama Administration officials that the data cannot currently be used to determine the scope of CWA jurisdiction, but rejects the premise that the tools we have today cannot be improved upon in the future to map WOTUS. The Water Subcabinet, leveraging the collective expertise, tools, and resources across the federal family, is working together with our state and tribal partners to do so.