File Geodatabase Feature Class
Tags
estuaries, estuary, estuary extent, tidal wetlands, West Coast, Pacific Marine and Estuarine Fish Habitat Partnership, PMEP
Data clipped to the state of California with a 5 mile buffer by CDFW staff ------------------------------------------------------------------------------------------------ This layer represents the current and historical tidal wetlands, or estuary extent, for the West Coast of the contiguous United States.
Accurate mapping of tidal wetlands is vital for effective conservation and restoration of these valued habitats, and good mapping is key to strategic planning for coastal resilience. Tidal wetlands are defined by regular inundation by the tides; therefore, mapping of tidal wetlands should be based on knowledge of tidal water levels and the land areas inundated by the tides. We developed this tidal wetland mapping following that principle.
Briefly, we used a method developed in Oregon that combines NOAAs extreme water level models (
https://tidesandcurrents.noaa.gov/est/
) with high-resolution LIDAR digital elevation models (DEMs) to map areas subject to tidal inundation. We refined the mapping using additional data sources such as the National Wetland Inventory, local knowledge, and aerial photo interpretation. Detailed information on the Oregon methods can be found here:
http://www.coastalatlas.net/documents/cmecs/EPSM_CoreGISMethods.pdf
Our mapping includes areas currently inundated by the tides -- current tidal wetlands -- from ocean to head of tide, including the freshwater tidal zone. To assist restoration planning, our mapping also includes historical tidal wetlands -- areas that were historically inundated by the tides, but are no longer inundated by the tides due to human alterations to the landscape such as dikes and tide gates. Although the mapping does not yet distinguish current from historical (disconnected) tidal wetlands, a future mapping phase (currently in the data development phase) will provide that information.
Note: This subset of data represents the approximate extent of current and historical tidal wetlands for PMEPs 444 estuaries, excluding unassociated extents and mouth connection areas.
Pacific Marine and Estuarine Fish Habitat Partnership, PSMFC GIS, Oregon Coastal Management Program (Department of Land Conservation and Development), NOAA-NWFSC, PC Trask
This product is for informational purposes only and is not intended for navigational, legal, engineering, or surveying purposes; it is provided with the understanding that conclusions drawn from the information are the responsibility of the user.
Extent
| West | -124.8 | East | -117 |
| North | 49.0 | South | 32.5 |
| Maximum (zoomed in) | 1:5,000 |
| Minimum (zoomed out) | 1:20,000,000 |
This product was created by the Pacific Marine and Estuarine Fish Habitat Partnership, and is part of a spatial data system for estuarine and nearshore environments for the West Coast of the contiguous United States. For more information, email gis@psmfc.org Vers. 1.0.1: Fixed spelling errors in 2 estuaries (Tulalip Bay and Elwha River)
Pacific Marine and Estuarine Fish Habitat Partnership, PSMFC GIS, Oregon Coastal Management Program (Department of Land Conservation and Development), NOAA-NWFSC, PC Trask
These data cover estuaries from the U.S-Canada border to the U.S.-Mexico border. Estuaries were included based on their current or future potential to provide habitat for fish species. It is possible that this list will expand or contract over time, as determined by the needs of the Pacific Marine and Estuarine Fish Habitat Partnership (PMEP). Vertical Extent: Generally, the vertical extent of the dataset is from the highest head of tide point elevation to minus four meters Mean Lower Low Water (MLLW) for non-lagoonal estuaries in the Salish Sea, and to the modified CUSP shoreline for all other estuaries (see Process Step 1 for details). The exceptions are tidal and tidally-influenced polygons from the National Wetlands Inventory which extend beyond the 50% exceedance elevation.
This product is for informational purposes only and is not intended for navigational, legal, engineering, or surveying purposes; it is provided with the understanding that conclusions drawn from the information are the responsibility of the user.
Data clipped to the state of California with a 5 mile buffer by CDFW staff ----------------------------------------------------------------------------------------------------------------------------- These data are based on a combination of NOAA’s extreme water level models, high-resolution LiDAR digital elevation models (DEMs), estuarine and tidally-modified classes from the National Wetland Inventory (NWI), local knowledge, and aerial photo interpretation. The Oregon Coastal Management Program (Oregon Department of State Lands) developed this methodology and mapped the major estuaries within Oregon (excluding the Columbia River), and we have extended this to include estuaries in Washington and California, as well as a few estuaries not included in Oregon’s effort. For detailed background on Oregon’s methods, please visit http://www.coastalatlas.net/documents/cmecs/EPSM_CoreGISMethods.pdf . Generally, the individual component spatial data sources are stored and maintained in a companion dataset (“PMEP Estuary Extent Sources”), which is dissolved into the final polygons representing the current and historical estuary extent and attributed with various estuary information. This is accomplished through Esri’s ModelBuilder tool, a visual programing language for building GIS workflows, allowing for numerous geoprocessing steps to be automated, and for repeated use and providing documentation for the process. All associated spatial data are maintained in a custom Transverse Mercator coordinate system, a West Coast regional projection with minimal distortion of distance and area. Any calculations of area within these data utilize this projection. Data are then projected for publishing online, generally using the WGS 1984 Web Mercator (auxiliary sphere) coordinate system.
Use NOAA’s Continually Updated Shoreline Product (CUSP), and Oregon’s Continually Updated Shoreline Product (OCMP CUSP) in order to establish the seaward extent of the estuaries (only for estuaries outside of the Salish Sea). The two shoreline datasets were merged into one layer, ‘Shoreline_PMEP_CUSP_wcm”, after creating a field (“DataSource”) to track the inputs. A new field was added to code the type of shoreline feature (“PMEP_Type”). Options in this field include “coast” (outer coast), “inside estuary”, “N/A” (sea stacks, rocks, islands, etc.), “remove” (NOAA’s CUSP overlapping with Oregon’s CUSP), and “seaward” (newly digitized line to limit seaward estuary extent). Any features created outside of the two data source inputs will have “DataSource” = ‘PMEP’. The only other changes to the input geometry involve splitting the line segments at specific locations, and assigning shorelines types in a new field, “PMEP_Type”, as appropriate.
This layer allows for the establishment of a consistent seaward boundary for estuaries along the outer coast of the Pacific Ocean, following the Coastal and Marine Ecological Classification Standard (CMECS). For those estuaries which have shoreline data extending internally within the estuary, a new feature (or features) was created to establish the seaward extent.
Based on Oregon’s methodology, select classes of the National Wetlands Inventory (NWI) that extended beyond the 50% exceedance layer were appended to the dataset, which will now be called ‘PMEP Estuary Extent Source’ layer. This will be the primary spatial layer which is appended to and modified in the development of the estuary extent layer in the following Process Steps. NWI classes appended to the dataset are, all Estuarine system classes and all Palustrine and Riverine system classes with tidal modifiers (‘S’, ‘Q’, ‘R’, ‘T’, and ‘V’). All NWI codes within the PMEP Estuary Extent Selector polygon were exported into a table and the “Attribute” field was decoded into the NWI levels (System, Subsystem, Class, Subclass, and Modifiers) for ease of use. It was determined that certain Attributes within these codes contained case errors which caused incorrect Attribute level codes to be assigned. The NWI Wetland Coder Interpreter tool (available @ https://www.fws.gov/wetlands/data/wetland-codes.html) was used to fix these errors. Examples of this error are: E1UBLH (should be E1UBLh) and E2EMPS (should be E2EMPs).
Based on Oregon’s determination and PMEP’s technical experts, it is thought that the National Wetlands Inventory is conservative in its classification of tidal wetlands, so the inclusion of these NWI Estuarine and tidally-modified classes where they extended beyond the 50% exceedance layer is warranted.
Using available imagery sources, including the National Agriculture Imagery Program (NAIP), historical imagery available in Google Earth, and other imagery sources, a new extent type was added to the PMEP Estuary Extent Sources layer to depict areas beyond the current estuary extent where the estuary mouth was present in other imagery sources. These polygons are contiguous with the mapped estuary, and are inland of the PMEP shoreline layer.
The estuary extent as mapped, is based on specific LiDAR sources and the National Wetlands Inventory (NWI), which represent static snapshots of the estuary at the time of data collection. Many estuaries are quite dynamic, and the locations of their features, especially near the interface of the estuary and the ocean, can vary greatly over time due to various factors. The addition of the “mouth connection” extent type attempts to capture the range of movement of the estuary mouths during recent history. This extent type is not included in the estuary area calculations, and is for reference purposes only.
The extent of the Estuary Regional Technical Group’s (ERTG) Columbia River 2 Year Flood Elevation (also called “50% Annual Exceedance Probability”) was appended to the PMEP Estuary Extent Sources layer, where it extended beyond the current extent of that layer.
There were minor differences in the methods used to calculate the 50% exceedance used by PMEP and the ERTG. Upon examination of both layers, it was decided by PMEP technical experts that the ERTG’s 50% Annual Exceedance Probability layer would be added to the PMEP Estuary Extent Sources layer, where it extended beyond PMEP’s mapped estuary extent sources.
For California estuaries classified as lagoonal, append the estuary extent for those areas which are beyond the current PMEP Estuary Extent Source layer, using data from “An Inventory and Classification of U.S. West Coast Estuaries” (Heady, et. al, 2015). These data were created through a process which included digitizing based on the latest aerial imagery (Landsat, Google Earth, and the California Coastal Records Project), where NWI or other sources were obviously incorrect, or not available.
Because lagoonal systems intermittently disconnected from the ocean by sediment accumulations, the mapped extent based on the 50% annual exceedance methods can be smaller than their true size. Also, these systems are often not well represented in NWI, and some small systems are missing entirely. For these reasons, it was decided that the lagoonal estuaries in California will include those extents as digitized in “An Inventory and Classification of U.S. West Coast Estuaries”.
The Pacific Marine and Estuarine Fish Habitat Partnership (PMEP) conducted an internal review process to solicit feedback on the draft estuary extent mapping. A password-protected web mapping application was created to allow PMEP members to provide input on the estuary layer. Once input was complete, these point locations were categorized into types based on the nature of the input given. Feedback which was determined to be actionable and within the scope of the current process was categorized as such. Edits were then made to the PMEP Estuary Extent Source layer, or the PMEP Estuary Extent Selector layer, as necessary to make the desired modifications.
PMEP members come from many different organization and agencies, and possess expert knowledge about estuary systems along the West Coast. This group’s input on the estuary mapping during the data development phase improved the mapping of specific locations and provided valuable feedback, based on their intimate knowledge of these systems.
The 50% Exceedance layer established the upslope extent of the current and historical estuaries in the Salish Sea region, but there needed to be a process to determine which areas would be specifically established in PMEP’s estuary mapping. Previously, the “Inventory and Classification of U.S. West Coast Estuaries” (Heady, et. al., 2015) had utilized the seven estuary subbasins for the U.S. portion of the Salish Sea, as established by the Puget Sound Nearshore Ecosystem Restoration Project (PSNERP). PMEP desired to map individual Salish Sea estuaries within these subbasins in greater detail, using the 50% Exceedance layer and NWI sources for geometry. The PSNERP technical report “2012-01: Strategies for Nearshore Protection and Restoration in Puget Sound” (http://www.pugetsoundnearshore.org/technical_papers/psnerp_strategies_maps.pdf) developed a landscape-based framework for restoration and protection of nearshore ecosystem sites. This report included a detailed assessment of 1,544 overlapping sites among four landscape classes: deltas (16), beaches (744), barrier embayment systems (518), and coastal inlets (266). Data representing site potential and degradation were developed and analyzed using both remotely-sensed and field data. For each strategy, sites were ranked using a potential score, and were placed into groups, based on their similarity. Groups of sites with the highest ranking were assigned a high potential score. All site data from this assessment can be found in Appendix B of the report. Sites in bold with darker shading are “high potential” sites based on potential group, as discussed in the report recommendations section. While PSNERP’s nearshore sites are mapped using different methods and at a different scale than the estuaries as mapped by PMEP, we utilized this resource to cross-reference PMEP’s estuary extent with the high-potential barrier embayment and coastal inlet sites, as identified in the report and the associated geodatabase. We included these locations in our estuary mapping, with other mapped estuary extent areas becoming “unassociated extents” in the PMEP data structure. We also included all 16 major river deltas in our mapping products. Nearly 150 estuaries in the Salish Sea PMEP Region were identified and explicitly included in PMEP’s mapping products by referencing the PSNERP technical report’s high-potential sites.
The PSNERP technical report “2012-01: Strategies for Nearshore Protection and Restoration in Puget Sound” is a detailed document which was created through a multi-stakeholder effort between government agencies, universities, tribes and environmental organizations. It lays out their strategy very clearly, and uses quantitative metrics to support ranking of their units and the determination of high priority sites. It is a great resource for the region and PMEP chose to utilize it to ensure that, at a minimum, the high priority sites identified in the PSNERP report were included in PMEP’s estuary extent mapping.
For non-lagoonal estuaries in the Salish Sea region, a layer was created to consistently establish a seaward boundary for the mapped estuary extents. It was determined that the most suitable layer for this purpose would be a bathymetric depth contour. For lagoonal systems in the Salish Sea, the shoreline layer determined the seaward boundary. GIS Specialist Hiroo Imaki (NOAA Northwest Fisheries Science Center) created line layer depicting the 4 meter depth contour below Mean Lower Low Water (MLLW), using NOAA’s (National Geophysical Data Center) Integrated Models of Coastal Relief digital elevation models (DEMs). PSMFC GIS staff projected the data to the West Coast Custom Mercator projection and then applied a line smoothing algorithm to this layer in order to produce a more natural looking depth contour layer (Smoothing Algorithm = PAEK, Smoothing Tolerance = 50 meters). Once the smoothing was applied to the Minus 4-meter MLLW layer, all non-lagoonal estuaries in the Salish Sea region were extended, or trimmed so that the seaward extent was coincident with this line. This process added a new type of source to the PMEP Estuary Extent Sources layer for some Salish Sea estuaries, called “minus 4 MLLW extension”.
The 4-meter depth contour below MLLW was established as the seaward boundary for Salish Sea estuaries because this contour is used in the Coastal and Marine Ecological Classification Standard (CMECS) to divide the Estuarine System into the Coastal and the Estuarine Open Water subsystems. According to CMECS, “the 4 meter contour was selected as a cutoff between coastal and offshore estuarine waters because it identifies (somewhat arbitrarily) a region that is both shallow and generally in close proximity to the shore, making the substrate-to-water volume ratio here the highest in the entire estuary…. The high wetland-water ratio and pelagic-benthic connectivity makes the Estuarine Coastal Subsystem an extremely dynamic and active area in terms of hydrodynamics, geology and biology.”
The series of steps required in order to transform the PMEP Estuary Extent Source layer into the final estuary extent layer involves a number of geoprocessing tasks, many of which are accomplished using the ModelBuilder tool in ArcCatalog (part of Esri’s ArcMap product). This visual programing language for building GIS workflows allows for numerous geoprocessing steps to be automated, allowing for repeated use and providing documentation for the process. The following steps are required for deriving the final estuary extent layer from the PMEP Estuary Extent Source layer: Model 1: PMEP_Estuary_Extent_Processing_01 Dissolves selected features from the ‘PMEP Estuary Extent Sources’ layer into contiguous features. Those features not included in this process include those flagged as being outside of the estuary extent, extents digitized to represent the range of the estuary mouths (estuary mouth connection areas), as well as any estuary extents which overlap with Oregon’s estuary mapping. Dissolves line features in ‘PMEP Estuary Extent Split Lines’ layer based on “LineGroup” field. Manual Process 1: Split estuary extent using dissolved split lines. Bring the 2 output layers (“PMEP_Estuary_Extent_Split_Lines_Dissolved” and “PMEP_Estuary_Extent_Dissolve_Model01”) created in the model “PMEP_Estuary_Extent_Processing_01” into an ArcMap session. Make the line layer the only selectable layer and start editing the polygon layer. Open the line layer and select one feature (e.g. LineGroup = 1). On the Advanced Editing toolbar, click on the Split Polygons tool. When prompted, select the Target to be the polygon layer (“PMEP_Estuary_Extent_Dissolve_Model01”), then click OK. This will split the polygon using the selected line feature, effectively dividing the estuary extent into two or more features. Repeat this step for all remaining features in the line dataset. Save edits when done. Model 2: PMEP_Estuary_Extent_Processing_02 This model takes the output of the splitting step (PMEP_Estuary_Extent_Dissolve_Model01), the Oregon Coastal Management Program’s (OCMP) estuary extent (CMECS aquatic and biotic layers, dissolved), and the estuary mouth connection areas and attributes them with codes indicating their extent type and data source. These layers are then merged into one dataset, “PMEP_Estuary_Extent_Merged”. Manual Process 2: Split Select OCMP estuaries using dissolved split lines. Add the layer “PMEP_Estuary_Extent_Merged” and the “PMEP_Estuary_Extent_Split_Lines_Dissolved” layer into an ArcMap session. Make the line layer the only selectable layer and start editing the “PMEP_Estuary_Extent_Merged” layer. Open the line layer table and select LineGroup = 22. On the Advanced Editing toolbar, click on the Split Polygons tool. When prompted, selecte “PMEP_Estuary_Extent_Merged” as the target, and then click “OK”. Repeat with LineGroup = 23. Save edits when done. Manual Process 3: Assign IDs/Associate Extents This step takes the estuary extent layer and performs a simple spatial join to associate IDs from the overlay layer with those polygons within them. Note that this tool causes the ModelBuilder application to crash, so it must be done from the tool in ArcCatalog, or within an ArcMap session. Spatial Join Tool Parameters: Target Features: PMEP_Estuary_Extent_Merged Join Features: PMEP_Estuary_Extent_Overlay_Selector Output Feature Class: PMEP_Estuary_Extent_Merged_Selector_Join Join Operation: JOIN_ONE_TO_ONE Keep all target features: yes Field Map of Join Features: Extent_Type (Text) Date_Source (Text) Extent_Type (Text) PMEP_EstuaryID (Short) Estuary_Name (Text) Link (Text) Match Option: WITHIN Model 3: PMEP_Estuary_Extent_Processing_03 This model dissolves the estuary extent areas and the mouth connection areas at the Estuary ID level. It also attributes unassociated extent areas. It then merges the three components into a new dataset, and then calculates the area (in acres) of each type of estuary extent. Model 4: PMEP_Estuary_Extent_Processing_04 This step calculates the area of each estuary extent polygon in acres (using the custom West Coast Mercator projection) and categorizes them as estuary acres, or as other areas (e.g. mouth connection areas do not count towards estuary area). It also joins a count of the number of contiguous estuary polygons which make up the multi-part dissolved estuary extent.
These steps allow the final estuary extent layer to be created in a logical and consistent manner, based on updates to the source inputs and geometries. These steps also associate data from PMEP with the estuary extent polygons.
Following Oregon’s methods, an upper boundary for intertidal wetlands was created using NOAA’s Extreme Water Levels analysis (https://tidesandcurrents.noaa.gov/est/). NOAA Extreme Water Levels analysis provides several exceedance level water elevations (1%, 10%, 50%, and 99%). These represent annual probabilities of water levels exceeding the given elevation – probabilities of 1%, 5%, 50%, and 99% respectively. This analysis is based upon the observed water levels during a period of at least 30 years, which includes the water level elevations associated with storms and floods. Using field ground-truthing, Oregon’s team (Oregon Coastal Management Program – DLCD) determined that the 50% exceedance contour was a good fit for the approximate maximum extent of tidal wetland habitats. The 50% exceedance value was calculated using NOAA’s existing network of observed locations and NOAA’s Vertical Datum Transformation Tool, or VDatum (https://vdatum.noaa.gov/welcome.html). Values were extrapolated for the estuaries where no VDatum coverage were available using the Euclidean allocation method. The seaward boundary for Salish Sea estuaries was established using a depth contour of minus 4 meters NAVD88. (Note: This depth was updated to minus 4 meters MLLW during a later processing step.) Generally, elevation data came from the NOAA Office for Coastal Management Coastal Inundation Digital Elevation Model data. https://coast.noaa.gov/slrdata/ These DEMs are part of a series of DEMs produced for the NOAA Office of Coastal Management’s Sea Level Rise and Coastal Flooding Impacts Viewer. The DEMs include the best available LiDAR data known to exist at the time of DEM creation for each Weather Forecast Office (WFO). The resolution of each DEM is approximately 5 meters, though some areas may have higher resolutions. Downloaded from https://coast.noaa.gov/htdata/raster2/elevation/SLR_viewer_DEM_6230/ - WA_SEW1_GCS_5m_NAVD88m - WA_SEW2_GCS_5m_NAVD88m - WA_SEW3_GCS_5m_NAVD88m - WA_PQR_GCS_5m_NAVD88m - OR_MFR_GCS_5m_NAVD88m - OR_PQR1_GCS_5m_NAVD88m - OR_PQR2_GCS_5m_NAVD88m - CA_EKA1_GCS_5m_NAVD88m - CA_EKA2_GCS_5m_NAVD88m - CA_LOX1_GCS_5m_NAVD88m - CA_LOX2_CGS_5m_NAVD88m - CA_MTR1_GCS_5m_NAVD88m - CA_MTR2_GCS_5m_NAVD88m - CA_MTR3, GCS_5m_NAVD88m - CA_SGX_GCS_5m_NAVD88m Additional elevation data utilized in the Salish Sea region includes the Combined bathymetry and topography of Puget Lowland (Finlayson, 2005), and the Puget Sound Digital Elevation Model (Finlayson, 2000). Finlayson D.P., Haugerud R.A., Greenberg, H. and Logsdon, M.G. (2000) Puget Sound Digital Elevation Model. University of Washington, (https://www.ocean.washington.edu/data/pugetsound/psdem2000.html Finlayson D.P. (2005) Combined bathymetry and topography of the Puget Lowland, Washington State. University of Washington, (https://www.ocean.washington.edu/data/pugetsound/psdem2005.html) Additional elevation data utilized in the San Francisco Bay/Sacramento-San Joaquin Delta region came from California Department of Water Resources, NOAA, and USGS. 1. 10-meter bathymetry - California DWR: (https://data.noaa.gov/dataset/2009-2011-ca-coastal-california-topobathy-merged-project-digital-elevation-model-dem) 2. 2-meter topo/bathy – NOAA (https://data.noaa.gov/dataset/2009-2011-ca-coastal-california-topobathy-merged-project-digital-elevation-model-dem) 3. 10-meter Digital Elevation Model – USGS National Elevation Dataset (https://catalog.data.gov/dataset/usgs-national-elevation-dataset-ned) Additional elevation data from the Puget Sound Lidar Consortium (http://pugetsoundlidar.ess.washington.edu/lidardata/) were utilized to cover areas around the Olympic Penninsula. Clallam County: 2001-02clallam http://pugetsoundlidar.ess.washington.edu/lidardata/restricted/projects/2001-02clallam.html Olympic Peninsula: 2005olympic http://pugetsoundlidar.ess.washington.edu/lidardata/restricted/projects/2005olympic.html Hoh River Watershed: 2012-13hoh http://pugetsoundlidar.ess.washington.edu/lidardata/restricted/projects/2012-13hoh.html
The development of this layer was a complex, iterative process including extensive review and input from PMEP members. For additional questions about specific methods used in the development of this layer, please contact PSMFC GIS staff (gis@psmfc.org).
NOAA’s Continually Updated Shoreline includes all national shorelines that have been verified by contemporary imagery and shoreline from other non-NOAA sources. This shoreline vector only includes shoreline and alongshore features that represent shoreline (groin, breakwater, and jetty). These data provide available contemporary high-resolution national shoreline. The shoreline is a representation based on an office interpretation of imagery or derived from Lidar. Shoreline vectors were verified with contemporary imagery. Sources of non-NOAA vector shoreline included U.S. Fish and Wildlife Service, North Carolina Department of Environment and Natural Resources, and U.S. Geological Survey. Non-NOAA imagery sources for interpreting shoreline included USDA-FSA Aerial Photography Field Office, ESRI Imagery World 2D (USGS, U.S. Geological Survey, and U.S. Department of Agriculture), Bing Maps Imagery Service, and Google Earth (TerraMetrics and DigitalGlobe).
This data layer is an element of the Oregon GIS Framework. The Oregon CUSP shoreline represents a "best of" attempt to create a continuous Mean High Water Shoreline for use in GIS analysis and inventory work. Whenever possible the Oregon CUSP shoreline references a mean-high water shoreline based upon vertical modelling or image interpretation, using both water level stations and/or shoreline indicators. CUSP is primarily built from LiDAR NGS National Shoreline data for the outer Pacific Ocean coast and Oregon Lidar Consortium data for the inner estuarine coast.
This data set represents the extent, approximate location and type of wetlands and deepwater habitats in the conterminous United States. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979). Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps.
State data for the Washington, Oregon, and California were downloaded on 1/29/2016 from the U.S. Fish and Wildlife Service website @ https://www.fws.gov/wetlands/data/State-Downloads.html on 1/29/2016, and were then merged into one seamless dataset, after removing duplicate features along the boundaries of the states.
Geometries for certain estuary systems in California were digitized as part of “An Inventory and Classification of U.S. West Coast Estuaries” (Heady, et. al., 2015). This inventory identified certain estuaries in California, especially lagoonal systems, were poorly represented in NWI and other available data sources. This group undertook a process to digitize these systems using the latest aerial imagery (Landsat, Google Earth) and the California Coastal Records Project.
Note that only the spatial data incorporated into PMEP’s mapping were for lagoonal estuaries in California.
Description from Resulting Study: The Expert Regional Technical Group (ERTG) of the Columbia Estuary Ecosystem Restoration Program conducted an Analysis of Water Levels for Site Delineation in Tidal-Dominated Regions (ERTG 2012-01, Rev 1) to identify sites suitable for restoration in the Columbia River Estuary. For this analysis, the ERTG developed a standard hydrological modeling method to determine the maximum water level that would recur every other year (the 2-year river flood event), which they also refer to as the “50% annual exceedance probability.”
Citation: PC Trask and Associates. United States Army Corps of Engineers 50% Annual Exceedance Probability Stage Profile for Survival Benefit Unit for the Lower Columbia River Estuary, 2011: Portland, OR.
These data cover the tidally-influenced areas of the lower Columbia River.
Members of the Pacific Marine and Estuarine Fish Habitat Partnership (PMEP) were provided the opportunity to review the estuary extent data during the data development process. Members provided input to the mapping based on their expert knowledge and professional experience with West Coast estuaries. In some cases, these inputs resulted in modifications to the estuary extent.
In order to establish a consistent seaward boundary for non-lagoonal estuaries in the Salish Sea, as well as to define estuary classes within the Coastal and Marine Ecological Classification Standard, a depth contour of minus 4 meters below Mean Lower Low Water (MLLW) was created by Hiroo Imaki (NOAA - NWFSC). This layer was created using NOAA’s Coastal Digital Elevation Models (DEMs), which integrate bathymetric and topographic DEMs and are used to support tsunami forecasting and warning efforts. These are also referred to as Integrated Models of Coastal Relief. DEMs Utilized: Arena Cove, Astoria_V3, Central OR Coast, Crescent City, Eureka, Fort Bragg, Garibaldi, La Push, Monterey, Port Orford, Port San Luis, Port Townsend, San Diego, San Francisco Bay, Santa Barbara, Santa Monica, Taholah. https://www.ngdc.noaa.gov/mgg/coastal/coastal.html The following datasets were used to fill in gaps in coverage of NOAA’s Coastal DEMs: Combined Bathymetry and Topography DEM of Western Washington State (October 2000): https://www.ocean.washington.edu/data/pugetsound/psdem2000.html California State Waters Map Series Data Catalog, from the California Seafloor Mapping Program (CSMP): Fort Ross and Salt Point https://pubs.usgs.gov/ds/781/ Central California, CA 1 arc-second MHW DEM, from NOAA’s National Geophysical Data Center (NGDC). https://www.ngdc.noaa.gov/dem/squareCellGrid/download/739 US Coastal Relief Model – Southern California Version 2, from NOAA’s National Geophysical Data Center (NGDC). https://www.ngdc.noaa.gov/mgg/coastal/grddas06/grddas06v2.htm PSMFC GIS staff applied a smoothing algorithm to the data (Smoothing Algorithm = PAEK, Tolerance = 50 meters) in order to produce a more natural appearing depth contour.
The extent of the Minus 4-Meter MLLW Depth Contour layer covers the entire contiguous West Coast of the United States, but the data is missing from a few select estuaries. Drayton Harbor (WA), the Columbia River (WA/OR), the Sacramento-San Joaquin Delta (CA), Los Angeles Harbor (CA), Anaheim Bay (CA), Newport Bay (CA), and Mission Bay (CA) estuaries all have missing depth data within part of the estuary.
The Oregon Coastal Management Program’s (OCMP) Oregon Estuary Project of Special Merit produced estuary and shorelands habitat map information, using the federally adopted Coastal and Marine Ecological Classification Standard (CMECS) version 4.0. For detailed documentation on the OCMP estuary mapping project, please visit http://www.coastalatlas.net/documents/cmecs/EPSM_CoreGISMethods.pdf.
This data source and associated documentation was utilized extensively throughout the development of this dataset, and served as an invaluable reference layer for applying this methodology to Washington and California. PMEP is thankful to OCMP staff for their pioneering work to map Oregon’s estuaries using the CMECS standard, and for their assistance with helping PMEP expand this important resource to the U.S. West Coast.
The estuary extent for most Oregon estuaries in PMEP’s estuary extent layer is based on a dissolved merge of the Aquatic Setting and Biotic Component layers from OCMP, which have some minor differences in extent. This data source is used for all estuaries within Oregon which were mapped as part of Version 0.4.1 of Oregon’s CMECS estuary mapping project. The “Data_Source” field identifies OCMP as the source for these estuary extents.
The data processing steps required in order to delineate estuary extents established contiguous polygons dissolved from various source inputs, representing the current and historical estuary extent. Certain estuaries coalesce into a single polygon from the various source inputs, but have been categorized and inventoried as separate, unique estuaries. A line layer, “PMEP Estuary Split Lines”, was created in order to split these larger polygons into single estuary extents. One example of an estuary “complex” requiring many dividing lines is the area from Cabrillo Marina to the Bolsa Chica Lowlands in Southern California. This area, encompassing both the Long Beach and Los Angeles Harbors, is divided into 11 individual estuaries from one large polygon, using this layer. Source geometry utilized in creating this splitting layer include the Watershed Boundary Dataset (USGS), regional data layers (Columbia River Estuary Ecosystem Classification, California Bay-Delta regions), shoreline data, and visual/heads-up digitizing.
The link between the estuary extent polygon layer, which is dissolved from various source inputs, and the estuary point layer, requires a companion layer to select these polygons and associate them with the point layer and estuary ID. The “Estuary Extent Selector” polygon layer was created to establish and maintain this link. This layer also establishes which estuary areas are considered part of a specific estuary, and which are considered as part of other, “unassociated” extents. This layer is utilized in the publishing of the estuary extent layer. Source geometry for this layer between contiguous estuaries is from the PMEP Estuary Split Lines layer. The other areas of geometry are based on general areas of contiguous or larger estuary extent polygons, and are used to identify and code estuary extent areas within the polygons. In some cases, this geometry has been modified to include or exclude estuary extent areas from association with a particular estuary system, based on expert review.
The extent of this layer covers all estuary extents as inventoried by PMEP. The simple geometry is used to select, and/or clip other datasets, including the Estuary Extent Source layer. No areas of these polygons overlap.
The PMEP Regions layer depicts ecoregions, used to categorize PMEP data into broad groups, reflecting differences in geography and large-scale marine processes affecting the estuaries. The original basis for these regions was the Marine Ecoregions of the World (MEOW) dataset from the World Wildlife Fund and The Nature Conservancy. This dataset was modified to capture inland watershed areas based on the Watershed Boundary Dataset, and some names were altered to commonly used West Coast names. Additionally, the boundary was altered between the Washington, Oregon, Northern California Coast Region (“Oregon, Washington, Vancouver Coast and Shelf” in MEOW dataset), and the Salish Sea Region (“Puget Trough/Georgia Basin” in MEOW), to include all estuaries along the Strait of Juan Fuca within the Salish Sea Region.
The seaward boundary of the layer is based on the 200 meter depth contour and international maritime boundaries. The inland boundary is based on watersheds which drain towards an estuary. In some cases (e.g. the Sacramento-San Joaquin Delta, the Columbia River), the inland boundary is based on HUC 10 watersheds which overlap the mapped estuaries. Divisions within the PMEP Region layer are based on watershed drainage (WBD) on land, and on the WBD and straight connecting lines for marine boundaries.
This layer represents the current and historical tidal wetlands, or estuary extent, for the West Coast of the contiguous United States. Note that estuaries were included based on their current or future potential to provide habitat for fish species.
PMEP
Internal feature number.
Esri
Sequential unique whole numbers that are automatically generated.
Feature geometry.
Esri
Coordinates defining the features.
The Extent_Type field categorizes the estuary layer into categories which establish which estuarine extent areas are part of PMEP’s inventory, and which are not (unassociated extents). Additionally, areas representing the recent variability in the location of the estuary mouths (“estuary mouth connection areas”), are coded in this field and do not contribute to the measured extent of an estuary.
PMEP
The organization, or organizations, whom provided spatial data for the estuary extent.
PMEP
unique identifier for each estuary included in PMEP estuary inventory
PMEP
This value represents the number of individual polygons which contribute to the estuary extent. Note that the final estuary extent layer is a multi-part feature type, and that many of the estuaries consist of many individual polygons. This value does not represent the number of PMEP Estuary Extent Source polygons, but represents the number of dissolved individual polygons which are derived from those data.
PMEP
These data are calculated as part of the estuary publishing process and are based on feature geometry representing the estuary extent.
The name of the estuary. Values in this field were generally obtained from the names in the “An Inventory and Classification of U.S. West Coast Estuaries” (Heady, et. al, 2014), although there are exceptions. Estuaries added to the PMEP estuary list utilized official or commonly used estuary names, the name of the major river or creek connecting with the estuary, or used local landmarks in the absence of another name source.
PMEP
These data are based on geographic names.
"PMEP EstuaryID"_"Estuary Name" This unique key is used to link various data across the PMEP spatial data system.
PMEP
The PMEP Region (or ecoregion) which the estuary is located in.
PMEP
Landscape-level geomorphological features from the coast to mid-ocean spreading centers. These large features can cross tectonic settings, and they can be delineated at a scale of 1:1,000,000 (or greater) using bathymetric maps and other remote sensing data. Each setting will normally contain a wide variety of the smaller geoform features.
Coastal and Marine Ecological Classification Standard (CMECS), Federal Geographic Data Committee, 2012.
Length of feature in internal units.
Esri
Positive real numbers that are automatically generated.
Area of feature in internal units squared.
Esri
Positive real numbers that are automatically generated.
The area of the current and historical tidal wetlands of the estuary, in hectares, as calculated using Custom West Coast Albers projection. Note that “mouth connection area” extents are not included in this value.
PMEP
These data are calculated based on the feature geometry.
Accessed 6/3/2016
Prepared for the Bonneville Power Administration, U.S. Army Corps of Engineers, and NOAA Fisheries. Portland, Oregon.
Citation: Heady, W.N., K. O’Connor, J. Kassakian, K. Doiron, C. Endris, D. Hudgens, R. P. Clark, J. Carter, and M. G. Gleason. 2014. An Inventory and Classification of U.S. West Coast Estuaries. The Nature Conservancy, Arlington, VA. 81pp.
Citation: Lanier, A., T. Haddad, L. Mattison, and L. Brophy. 2014. Core CMECS GIS processing methods, Oregon Estuary Project of Special Merit. Oregon Coastal Management Program, Oregon Department of Land Conservation and Development, Salem, OR. Accessed 27 July 2016 at http://www.coastalatlas.net/documents/cmecs/EPSM_CoreGISMethods.pdf.
Citation: U.S. Fish and Wildlife Service. 5/10/2015. National Wetlands Inventory website. U.S. Department of the Interior, Fish and Wildlife Service, Washington, D.C. http://www.fws.gov/wetlands/
This product is for informational purposes only and is not intended for navigational, legal, engineering, or surveying purposes; it is provided with the understanding that conclusions drawn from the information are the responsibility of the user.