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EMAP and NCA: US Estuaries Map Services
Citation:
Harwell, L. EMAP and NCA: US Estuaries Map Services. U.S. Environmental Protection Agency, Washington, DC, 2025.
Impact/Purpose:
Access optional sub-product: EMAP and NCA: US Estuaries -- Web Map Services Overview: https://epa.maps.arcgis.com/home/item.html?id=a84abb4883f540beaa69528444cb8f24 The EPA Office of Research and Development’s (ORD) “Environmental Monitoring & Assessment Program (EMAP)” website (https://archive.epa.gov/emap/archive-emap/web/html/index.html), launched in 2006, was an EPA hosted, public-facing resource that served as a “clearinghouse” for numerous research products and data generated from and in support of the EMAP (1990-1996) and the National Coastal Assessment (NCA) Demonstration Project (2000-2006). The impact of EMAP and NCA research has been and continues to be far reaching – with approaches, methodologies and data informing research around the world. The EMAP website attracted approximately 12,000 visitors, annually (last calculated: 12/2021) where they could search through the single most comprehensive collection of estuarine monitoring and assessment research conducted throughout the 1990s and 2000s. EMAP and NCA research also informed the development and implementation of Office of Water’s National Aquatic Resource Surveys program. In 2021, the EMAP website was taken off-line and much of the historical data are not readily accessible. The research product submitted for review is the first of several efforts focused on reestablishing public access to research content that was historically offered through EPA’s website. The original geospatial boundaries and base data used to support EMAP and NCA research were retrofitted for EPA’s GeoPlatform. The “EMAP and NCA: US Estuaries” web map provides access to four map features that may be viewed on-line or downloaded for reuse. The maps contain spatial polygons that delineate estuarine and near-shore waterbodies for the marine coastal states of the US, the US Territories of American Samoa, Guam, and US Virgin Islands, and the Commonwealth of Puerto Rico. With minor exceptions, i.e., incorporating current EPA policies, these web-accessible feature layers are replicas of the geospatial boundaries and base map data that were originally developed to support EMAP and NCA research. Since then, these data have been and continue to be used to support numerous environmental applications (e.g., modeling, survey design, data analysis) and federal and state environmental programs. The purpose of this sub-product is to modernize access and minimize maintenance costs to publish data that has been previously available on EPA's website. QAPPs and SDMP were published as part of a series of EPA technical reports: U.S. EPA. 2001. Environmental Monitoring and Assessment Program (EMAP): National Coastal Assessment Quality Assurance Project Plan 2001-2004. United States Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Gulf Ecology Division, Gulf Breeze, FL. EPA/620/R-01/002. https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=30003YDF.txt Strobel, C.J. and R.M. Valente. 1995. Quality Assurance Report: EMAP-Virginian Province, 1990-1993. United States Environmental Protection Agency, National Health and Environmental Effects Research Laboratory, Atlantic Ecology Division, Narragansett, RI. September 1995. EPA/620/R-95/007. https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=P100C1SW.txt Hale, S S., J. Rosen, D. Scott, J F. Paul, AND M Hughes. EMAP INFORMATION MANAGEMENT PLAN:1998-2001, Vols I & II. U.S. Environmental Protection Agency, Washington, DC, EPA/620/R-99/001 (NTIS PB2000-100709), 1999. EPA/620/R-99/001a. https://nepis.epa.gov/Exe/ZyPURL.cgi?Dockey=300042HM.txt. Sub-product has been reviewed for content (CEMM Assistant Center Director- SSWR; CEMM Associate Director for Environmental Measurement; CEMM Program Communications) and quality (CEMM Director of Quality Assurance and Quality Assurance Manager; CEMM Scientific Data
Description:
Throughout the 1990's and 2000's, the U.S. Environmental Protection Agency's (EPA) Office of Research and Developed (ORD) conducted extensive research to enhance approaches used for environmental monitoring and assessment in estuarine resources. The four feature layers offered here were originally generated to support EPA's Environmental Monitoring and Assessment Program (EMAP, 1990-1994) and National Coastal Assessment Demonstration Project (NCA, 2000-2006). These maps delineate estuarine waters as defined by these two research efforts. CONUS, Alaska, and Puerto Rico maps were created using the United States Geological Survey's (USGS) intermediate-scale Digital Line Graphs (DLGs) dated 1983-1995. DLG's of map features are converted to digital form from maps and related sources. Intermediate-scale DLGs were data derived from USGS 1:100,000-scale, 30- by 60-minute quadrangle maps. When DLG data were unavailable, other sources were used (e.g., state maps, nautical charts) to fill spatial data gaps. Hawaii, U.S. Virgin Islands, American Samoa, and Guam datasets were generated using vectorized shoreline data derived from the one-meter panchromatic IKONOS imagery, augmented with USGS DLGs. Collectively, the four files contain 3,950 mapped estuarine polygons. Mapped polygons represent named estuarine waterbodies, including tidal rivers and near-shore waters in marine coastal areas. Names have been reconciled with the USGS National Map and Geographic Names Information System (GNIS), to the extent possible. Where available, ancillary information, such as ecoregion, biogeographical province, and salinity profile, has been included. These maps are intended to be used to inform applications in environmental research (e.g., modeling, geospatial analysis, mapping). Data may be accessed via GeoPlatform.
