78515 Data Set Published / External 79420 Benthic Project Completed 2026-02-17 In June 1995, the Columbia River Estuary Study Taskforce (CREST) obtained 295 true color aerial photographs (1:12,000) of Willapa Bay, Washington, from the Washington State Department of Transportation (WDOT). These photographs were suitable for interpreting submerged, rooted aquatic vascular plant populations. Field surveys were conducted in August 1995 by personnel from Oregon State University, the Columbia River Estuary Study Taskforce, and the Washington Department of Natural Resources. These surveys aimed at spectral signature development, verification, and habitat observation. The submerged plant populations were subsequently interpreted and mapped from the photographs and then transferred onto 1:12,000 orthophoto maps provided by the state of Washington. This information was digitized into a geographic information system to create a habitat map. The entire process, including interpretation, digitization, and photography acquisition, adhered to the rigorous parameters detailed in the Coastal Change Analysis Program protocol. Two supplementary datasets enhanced the interpreted habitat polygons. In 1996, WDOT provided color aerial videography for post-mapping verification and accuracy assessments. Additionally, the University of Washington collected videography from 29 underwater transects to specifically verify the deep-water edge of selected seagrass beds in the bay's southern portion. This videography included direct recording on the tape of date, time, geographic coordinates, and depth, updated every 2 to 4 seconds, with latitude and longitude provided by a differentially corrected global positioning system. The initial presence or absence map created by the taskforce was later segmented by depth to distinguish between two different seagrass communities and facilitate field accuracy assessment. Final field verification of the data was carried out in the summer of 1997 by CREST and NOAA Office for Coastal Management staff. The resulting benthic data is classified according to the System for Classification of Habitats in Estuarine and Marine Environments. This project aimed to establish national baseline data on benthic habitats and provide local resource managers with seagrass distribution information. A key focus was the distribution of Zostera japonica on intertidal mudflats and the threat posed by the expansion of Spartina alterniflora to the robust local oyster fishery. Healthy seagrass beds are vital, supporting endangered migratory waterfowl like the black brant, as well as commercially and recreationally valuable salmon. The layers available within the data download include biotic, geoform, and substrate. Partners: Columbia River Estuary Study Taskforce, Oregon State University, and the Washington State Department of Natural Resources To support the inventory of benthic habitat classification, extent, and health pursuant to the National Environmental Policy Act, the Rivers and Harbors Act, and the Coastal Zone Management Act. Bureau Code: 006:48, Program Code: 006:055 Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > BIOSPHERE > ECOSYSTEMS > MARINE ECOSYSTEMS > BENTHIC Theme Global Change Master Directory (GCMD) Science Keywords EARTH SCIENCE > BIOSPHERE > ECOSYSTEMS > MARINE ECOSYSTEMS > COASTAL Theme ISO 19115 Topic Category biota Theme ISO 19115 Topic Category environment Theme benthic Theme biotic Theme coastal Theme geoform Theme seafloor Theme seagrass Theme substrate Spatial United States of America Spatial Washington Office for Coastal Management Charleston SC Data Set None Planned Map (digital) Biotic: biotic_code, biotic_setting, biotic_class, biotic_subclass, biotic_group, percent_cover, description Geoform: geoform_code, tectonic_province, physiographic_province, geoform_origin, geoform Substrate: substrate_code, substrate_origin, substrate_class, substrate_subclass, substrate_group, description Any conclusions drawn from the analysis of this information are not the responsibility of NOAA, the Office for Coastal Management or its partners. All content is licensed under the CC0 1.0 Universal public domain dedication. NOAA Office for Coastal Management Point of Contact 2026-02 Organization NOAA Office for Coastal Management NOAA/OCM coastal.info@noaa.gov 2234 South Hobson Ave Charleston SC 29405-2413 (843) 740-1202 https://coast.noaa.gov NOAA Office for Coastal Management Home Page Online Resource Publication Date -124.0962 -123.7535 46.7546 46.3654 Discrete 1995-06-28 No Yes No No No Geometry Only Yes Geographic 2D EPSG:4269 NAD83 North American Datum 1983 GRS 1980 6378137 298.257222101 1 Geodetic Latitude Lat degree north 1 Geodetic Latitude Lat degree north 2 Geodetic Longitude Lon degree east 2 Geodetic Longitude Lon degree east Custom Unclassified These data were created for planning and management. Users should be aware of temporal changes that may have occurred since the collection of original source data sets. https://benthic-data-noaa.hub.arcgis.com/ NOAA Benthic Data Hub Registry https://marinecadastre.gov/downloads/data/benthic/willapa_bay_1995.zip A field accuracy assessment effort was conducted during the summer of 1997. Prior to making the field visit, the original presence/absence SAV map was segmented into shallow (-2 meters) and deep (greater than -2 meters) portions. The purpose of this was to draw verification samples not only from areas where SAV had been mapped, but from shallow areas that should support it. The result was a 6-class vector coverage that was rasterized and used as a pool for drawing random samples stratified by the shallow and deep-water class, shallow and deep-water SAV, unknown and the Spartina class. Sets of unknown polygons were directly measured. A total of 250 (50 samples per class) were randomly generated and stored as a database file to allow field measurement. A total of 95 sites were visited. The final results included an overall accuracy of 81.02 percent with a Kappa coefficient of 0.6842. Horizontal accuracy was not addressed during the field visit of 1997. Horizontal accuracy measures were the result of internal quality assurance and quality control values during the digitization process. This involved a comparison of the native aerial photography and the polygon coverage to an existing digital nautical chart. The chart and polygon data meets national map accuracy standards. The maximum Root Mean Square Error for the manual digitization process was 0.003 digitizer inches. Data is complete. All interpretable SAV habitat was mapped. Following the compilation process the arc vector coverage was cleaned and polygon topology was built using the arc CLEAN and BUILD commands. A further editing process was undertaken to remove sliver polygons generated during the bathymetric segmentation process. Conventional color metric aerial photography Organization Columbia River Estuary Taskforce Originator 1996-06-01 Conventional color metric aerial photographic images of Willapa Bay, Washington acquired by the Washington Department of Transportation, June 1996 (Edition: 1.0). The 295 images formed the basis for the mapping, and most of the habitat presence, location, and characteristics were derived by manually interpreting this imagery. Film transparency. GEODAS NOAA Point Bathymetric Records Organization NOAA National Oceanographic Data Center Originator Range 1877 1954 CD-ROM containing .txt files. which supported the generation of a -2 meter bathymetric contour State of Washington Orthophoto maps Organization Washington Department of Natural Resources Originator 1991-01-01 State of Washington Orthophoto imagery (1:12,000) Underwater videography Organization Marine Resources Consultants, Inc. Originator 1996-01-01 Underwater videography 1 Aerial Photography and Underwater Videography: On June 28, 1995, 295 conventional color metric aerial photographs at a scale of 1:12,000 were acquired through the State of Washington Department of Transportation (WDOT), using a Jena LMK-2015 camera with a 153 mm Jena Lamegon Lens (AV minus blue Jena 405) and Aerocolor 2445 film. The photographs had 60 percent overlap and 20 percent sidelap. The equipment and methodology used to collect the 295 images met rigorous parameters detailed in the C-CAP Protocol. Deviations to the C-CAP protocol were the use of color aerial videography, obtained in 1996, as an ancillary data source. Data from 29 transects of underwater videography were used to verify the deep-water edge of selected seagrass beds in the southern portion of the bay. 1995-06-28T00:00:00 2 Benthic Signature development and Photointerpretation: Field surveys were conducted in August of 1995, after initial review of the images to develop spectral signatures. Observations of SRV on photographs were accomplished using stereopairs and a Leitz stereoscope with a 2X magnifying attachment. Areas containing eelgrass were delineated with reference to spatial distribution, and data from pre-truthing activities were used as constant reference to verify spectral signatures. Mylar overlays, placed on every other photograph, were used for tracing polygons defining SRV habitat from the aerial photography. The minimum mapping unit was 30 square meters, in order to avoid mapping Spartina rather than eelgrass. 1995-08-01T00:00:00 3 Digital Compilation: The delineated polygons were transferred from the overlays to State of Washington Orthophotos (1:24,000). The interpretations were directly transferred and when necessary, due to scale differences, a zoom transfer scope was utilized. The final, corrected interpretations were digitized using a digitizing tablet. The bathymetric points were made into a grid using ArcView Spatial Analyst Extension. The bathymetric grid was used to generate a contour line of -2 meters. The contour was unioned with the CREST SAV coverage and recorded for shallow and deep grass classes, shallow and deep open water, unknown bottom, land, and Spartina. The coverage was rasterized and 50 random points per class (excluding land) were randomly chosen from the stratified data set using ERDAS Imagine software, for a total of 300 points. Field verification of the data by personnel from CREST and C-CAP was conducted in July 1997. The team utilized both underwater videography for deeper water points, and hand-held Hi-8 above water video for shallow, exposed tidal flats. The fieldwork revealed that the deep-water points consisted of dense Zostera marina, while the shallow exposed points were scattered patches of grass, primarily Zostera japonica. Based on the field data, the deep and shallow grasses were recorded as dense and patchy, respectively. 1997-07-01T00:00:00 4 The data were converted from a single ESRI polygon data set classified according to the System for Classifying Habitats in Estuarine and Marine Environments (SCHEME) to the Coastal and Marine Ecological Classification Standard (CMECS) 2012 format. This produced separate biotic, geoform, and substrate feature layers from the original input benthic habitat dataset. Each of the three feature layers contain respective CMECS biotic, geoform, and substrate component attributes where an "Equal" or "Nearly Equal" SCHEME value was present in the original data. Polygons for which no biotic, geoform, or substrate information was present have been removed. No other changes to the original polygon boundaries or any other alterations of the original SCHEME data were made during this process. 2015-01-01T00:00:00 5 Standardized common design elements, cleaned up field content, repaired geometry, and projected to NAD83. 2025-08-01T00:00:00 gov.noaa.nmfs.inport:78515 Jesse Brass 2025-11-03T20:16:06 Jesse Brass 2026-02-04T20:10:50 2026-02-04 Office for Coastal Management OCM 1002 Public No No 2026-02-02 1 Year 2027-02-02