This dataset contains spatial and attribute information of the Surface Water Quality Standards for the State of Washington, Chapter 173-201A WAC. Four views of the WQ Standard are contained in this dataset, Freshwater Beneficial Uses, Seasonal Supplemental Spawning and Egg Incubation Temperature Standards, rules designated in Table 602, and exceptions to Table 602 listed in the footnotes. If any discrepancies are found between GIS layers and the published rule, the published rule takes precedence. Updated March 2023.

These polygon features represent Water Quality Improvement (WQI) projects managed by the Washington State Department of Ecology. WQI projects can be TMDLs, Straight To Implementation (STI) plans, 4b projects and TMDL Alternatives. The boundaries show where the WQI project applies and is being implemented. TMDL Boundaries identified as "In Development" are considered draft and are subject to change when the project has been approved by the U.S. EPA. U.S. EPA only approves TMDLs and 4b projects. Boundaries are representations of each particular project and does not replace the official version of the approved TMDL report. Please see the TMDL Project webpage for specific information about that project. TMDL projects are required by the Federal Clean Water Act to identify pollution sources and pollution load reductions needed for water bodies to meet water quality standards. Once a TMDL project has been approved by the U.S. EPA, it enters an implementation phase where both point source and non-point source pollution is reduced through permit limits regulated under the NPDES system and through best management practices for land uses that contribute to non-point source pollution. Ecology’s water quality program works with permittees, local governments, watershed stakeholders, and residents to reduce sources of pollution to protect our aquatic resources and public health.

We have established a Vessel Sewage No Discharge Zone (NDZ) for Puget Sound and certain adjoining waters. The NDZ is a body of water where boats may not release sewage, whether treated or not. It helps protect public health, water quality, and sensitive resources. The NDZ (Chapter 173-228 WAC) was adopted on April 9, 2018, after a five year public process and approval from the Environmental Protection Agency (EPA). The rule was effective May 10, 2018. However, certain commercial vessels have a five year delay before the rule begins. There is no change for graywater discharges. For more information, visit Ecology's NDZ webpage.

The shapefile displays those basins within which development projects potentially qualify for using the existing land cover condition as the stormwater flow control default target. This is a lower flow control default target than the target used for most of western Washington, which is based upon use of the historic land cover condition.

From the site: "This map includes short descriptions of geologic units and a cross section showing the distribution of geologic units under the earth’s surface. Among other uses, the map will provide users with a better understanding of the distribution, depths and thickness of Marcellus Shale. This map will be especially useful in showing the interplay between geologic formations and groundwater availability and quality.

The map updates geologic information to be consistent with adjacent states, redefines boundaries between formations from the previous maps, and updates the subsurface geologic cross section based on new review of geologic cores and geophysical logs. The geologic information is available to users in Geographic Information System (GIS) format. A printable PDF version is also available. At this time we do not plan to offer a printed version of this map. The map is about 36 inches high by 60 inches wide when printed. If you do not have access to a large-format printer you can take the PDF file to a desktop publisher or office supply store and have it printed.

This product was assembled at a scale of 1:100,000. Using the map or data a smaller scale, such as 1:60,000 or 1:24,000, can result in serious positional errors. All data, information, and maps are provided "as is" without warranty or any representation of accuracy, timeliness of completeness. The burden for determining accuracy, completeness, timeliness, merchantability and fitness for or the appropriateness for use rests solely on the user. Maryland Department of Natural Resources makes no warranties, express or implied, as to the use of the information obtained here. There are no implied warranties of merchantability or fitness for a particular purpose. The user acknowledges and accepts all limitations."

Major river lines in the Salish Sea Bioregion. Lines were simplified for cartographic purposes. All processing and analysis was completed using the NAD 83 UTM Zone 10N projection and coordinate system.Analysis and cartography by Aquila Flower.Rivers locations based on:USGS National Hydrography Dataset hosted by the Washington Department of Ecology (https://ecology.wa.gov/Research-Data/Data-resources/Geographic-Information-Systems-GIS/Data).National Hydrography Network hosted by the Canadian Open Data portal (https://open.canada.ca/data/en/dataset/a4b190fe-e090-4e6d-881e-b87956c07977).Monthly discharge records calculated using 1981-2010 data from:Historical Hydrometric DataUSGS National Water Information System

AbstractThe basin delineation was initially derived using standard watershed tools and DEM's (from NOAA). The computer generated watershed boundary was then manually edited via visual interpretation using topo maps, the DEM files and other watershed boundary maps (notably from the Sea Doc Society). The majority of the editing was in smoothing the original watershed boundary as the auto generated basin was far too detailed for the scale of the map. The smoothing process also removed the ‘raster’ artifacts. For the Salish Sea map the intent was just to show the general boundary as a smooth line that visually follows the topography. Again, the emphasis was for an easy to understand cartographic representation of the basin at a fairly coarse scale, not for exact hydrologic analysis.PurposeFor the purposes of this map & dataset, the Salish Sea was defined as including: Puget Sound, Desolation Sound (note, some BC definitions exclude Desolation Sound), Strait of Juan de Fuca (to the mouth of the Pacific Ocean), Strait of Georgia (which I defined as extending to Johnstone Strait). The Salish Sea polygon and corresponding Basin boundary files were derived for use at approximately 1:1,500,000 (e.g., Salish Sea Map, 2009, http://staff.wwu.edu/stefan/SalishSea.htm).Data creditStefan Freelan, 2009 stefan@wwu.edu 360-650-2949Institute for Spatial Information and AnalysisHuxley College of the Environment, Western Washington UniversityBellingham, WA 98225-9085http://staff.wwu.edu/stefan/SalishSea.htm

The land base of the Pacific Northwest includes large areas that could support hardwoods or a hardwood component. Often, however, site index, the most commonly used measure of a site's potential productivity, is not available for red alder as other species occupy the site. In order to make site-specific management decisions, the suitability for red alder production can be assessed by geographic and topographic position, soil moisture and aeration during the growing season, and soil fertility and physical condition (Harrington 1986). The difficulty of weighing these physical factors to determine site suitability appears to be a major impediment to the establishment of red alder plantations. Additionally, forest managers are lacking a planning tool that would consider red alder in the landscape for long term management plans. To assist forest managers in their planning and site selection efforts, we developed a GIS-based Red Alder Site Suitability Model based on physical criteria identified by Harrington (1986) as most influential on the productivity of red alder. The major components of the model are elevation, topographic position, slope, aspect, soil type, and soil depth. The model was implemented in a GIS (ESRI ArcPro v.3.0) raster environment with topographic position, slope, aspect, and elevation derived from a 10-meter digital elevation model (DEM), using lidar data where available. Topographic position class of valley, lower slope, flat slope, middle slope, upper slope, or ridgetop was derived from the topographic position index (TPI) using standard deviation thresholds as described by Weiss (2001). The soil texture and depth were derived from Washington DNR’s corporate soil data layer. Each pixel was then classified and assigned one of four suitability categories: High, Medium, Low, and No Potential. Because of the level of spatial detail of the model, forest managers can assess the potential of red alder management on any given site, such as planned timber harvest. Additionally, the model can be used at a larger scale, i.e. planning for future product diversification in a watershed.The model has been cursorily field-verified on existing red alder plantations and compared with locations and site index of natural red alder stands for DNR's forest inventory system. Initial results indicate that the model is accurate in identifying sites with potential for intensive red alder management. Local knowledge will still be an important factor in the application of the model. Frost pockets or areas susceptible to other physical damage such as ice damage (i.e. within the east wind drafts of the Columbia River Gorge) are not identified in by this model. The usefulness of this model will be determined by the experience of the field staff over time. References:Harrington, Constance A. 1986. A method of site quality evaluation for red alder. Gen. Tech. Rep. PNW-GTR-192. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 22 p. https://doi.org/10.2737/PNW-GTR-192Weiss, A. 2001. Topographic position and landforms analysis. In Poster presentation, ESRI user conference, San Diego, CA (Vol. 200). http://www.jennessent.com/downloads/tpi-poster-tnc_18x22.pdf

Approximate prevailing (most frequent) wind direction for January at select climate stations in the Salish Sea Bioregion, based on 1991-2020 records.Arrows indicating prevailing wind direction were created based on records housed by Iowa State University as part of the Iowa Environmental Mesonet website.

Digital Elevation Model for the Salish Sea Bioregion. 3-arc second (approximately 90 meter) spatial resolution.This dataset was created using NASA's SRTM data post-processed by CGIAR CSI. SRTM tiles were combined as a Mosaic dataset using "blend" where they overlapped. The combined dataset was re-projected to UTM using Cubic Convolution resampling. The resulting Digital Elevation Model was clipped to the Salish Sea Atlas's Land dataset to remove any areas defined as marine waters. Low-lying coastal areas with missing data due to small mismatches in the coverage of bathymetry and elevation data in Canada were corrected by recalculating the elevation as 0 meters asl. Note that Piers Island, north of Swartz Bay, has no elevation data available.You can download a .TIFF copy of this raster dataset here.

Marine Waters of the Salish. Created for the Salish Sea Atlas (wp.wwu.edu/SalishSeaAtlas).Simple polygon representation of the marine waters of the Salish Sea. Boundaries of the Salish Sea were digitized based on the legal definition from BC Geographical Names (https://apps.gov.bc.ca/pub/bcgnws/names/53200.html), with the help of marine water body definitions from the BC Freshwater Atlas and USGS's National Hydrography Dataset. Coastlines were defined using the Washington ShoreZone Shoreline and British Columbia Freshwater Atlas shoreline. Note that the northern and western boundaries of the Salish Sea are often shown as slightly different on different maps. Here, I use the definition of the northern boundary used in the BC Freshwater Atlas, which they based on the BC Geographical Names Information System definition. For the western border, I found many slightly different definitions of precisely where the mouth of the Strait of Juan de Fuca is. Finding no consensus, I digitized a straight line from the southwestern corner of a Strait of Juan de Fuca basin polygon obtained from NOAA to the northwestern corner of the Strait of Juan de Fuca polygon in the BC Freshwater Atlas.

HUC-8 level US watersheds and sub-sub-drainage basin level Canadian watersheds that directly or indirectly drain into the Salish Sea, including all upper Fraser River drainage basin watersheds. All processing and analysis was completed using the NAD 83 UTM Zone 10N projection and coordinate system.Analysis and cartography by Aquila Flower.US Hydrologic Unit Code level 8 (HUC-8) NHD watershed boundaries from the USGS National Hydrography Dataset hosted by the Washington Department of Ecology (https://ecology.wa.gov/Research-Data/Data-resources/Geographic-Information-Systems-GIS/Data)."Water Survey of Canada Sub-Sub-Drainage Area" (WSCSSDA) NHN watershed boundaries from the National Hydro Network hosted by the Canadian Open Data portal (https://open.canada.ca/data/en/dataset/a4b190fe-e090-4e6d-881e-b87956c07977).

Complete stream network for the Salish Sea Bioregion. Stream, river, ditch, and canal line features were merged and harmonized using data from the BC Freshwater Atlas and the USGS National Hydrography Dataset. Lines were manually edited for obviously incorrect overlaps or gaps along the international border. The merged dataset was clipped to the Salish Sea Bioregion boundary as defined in the Salish Sea Atlas. Attributes were simplified and harmonized. All processing and analysis was completed using the NAD 83 UTM Zone 10N projection and coordinate system.Analysis and cartography by Aquila Flower. Washington stream lines from the USGS National Hydrography Dataset hosted by the Washington Department of Ecology (https://ecology.wa.gov/Research-Data/Data-resources/Geographic-Information-Systems-GIS/Data). British Columbia stream lines from the BC Freshwater Atlas hosted by the BC Data Catlogue (https://www2.gov.bc.ca/gov/content/data/geographic-data-services/topographic-data/freshwater).

These polygon features represent the TMDL projects managed by the Washington State Department of Ecology. The boundaries show where the TMDL project applies and is being implemented. TMDL Boundaries identified as "In Development are considered draft and are subject to change when the TMDL has been approved by the U.S. EPA. Boundaries are representations of each particular project and does not replace the official version of the approved TMDL report. Please see the TMDL Project webpage for specific information about that project. TMDL projects are required by the Federal Clean Water Act to identify pollution sources and pollution load reductions needed for water bodies to meet water quality standards. Once a TMDL project has been approved by the U.S. EPA, it enters an implementation phase where both point source and non-point source pollution is reduced through permit limits regulated under the NPDES system and through best management practices for land uses that contribute to non-point source pollution. Ecology’s water quality program works with permittees, local governments, watershed stakeholders, and residents to reduce sources of pollution to protect our aquatic resources and public health.

Western Washington land cover change analysis.

Detailed land cover classes for the Salish Sea Bioregion. Based on 30x30 meter Landsat imagery from 2015 (Canada) or 2016 (USA).This land cover classification was derived from the North American Land Change Monitoring System. Land cover classes were subset, combined, and renamed to create a simpler set of classes customized for this region. Some areas' land cover classes were manually modified based on comparison with USGS GAP land cover data and recent aerial imagery. Most of these manual modifications were along the coastline. This dataset still seems to under-represent intertidal mudflats compared with the GAP land cover classification. The dataset was clipped to the Salish Sea Bioregion boundary from the Salish Sea Atlas. All processing and analysis was completed using the NAD 83 UTM Zone 10N projection and coordinate system.This is a tile layer designed for cartographic purposes. You can also download a .TIFF version of the file for analysis purposes from the Salish Sea Atlas website.

Based on 30x30 meter Landsat imagery from 2010. Extracted from NASA's Global Man-made Impervious Surface Dataset V1. Null values were removed and the dataset was clipped to the Salish Sea Bioregion boundary from the Salish Sea Atlas. All processing and analysis was completed using the NAD 83 UTM Zone 10N projection and coordinate system.

Mainland and islands within the Salish Sea Bioregion with a database of island names, small island chain names, and larger archipelago names.Island names were derived from the British Columbia Freshwater Atlas or transcribed from Google Maps. Where no name could be find, the name field was left blank.Coastlines were defined using the Washington ShoreZone Shoreline and British Columbia Freshwater Atlas shoreline. ShoreZone was given precedence where the datasets overlapped. ShoreZone gaps like river mouths were bridged with a straight line. Shoreline line features were converted to polygons. Multipart polygons were split and inland islands were removed. The entire dataset was clipped to the Salish Sea Bioregion boundary.All processing and analysis was completed using the NAD 83 UTM Zone 10N projection and coordinate system.Coastline data modified from a product created by Coastal Geologic Services, based on data from the British Columbia Freshwater Atlas (https://catalogue.data.gov.bc.ca/dataset/freshwater-atlas-islands) and the Washington State ShoreZone Inventory (https://www.dnr.wa.gov/programs-and-services/aquatics/aquatic-science/nearshore-habitat-inventory).

Bathymetry for the Salish Sea. 3-arc second (approximately 90 meter) spatial resolution. Vertical datum: approximately Mean Sea Level.Separate datasets for British Columbia and Washington data were downloaded from NOAA, converted from NetCDF to raster, and then combined as a Mosaic dataset using "blend" where they overlapped. The combined dataset was re-projected to UTM using Cubic Convolution resampling. The bathymetry dataset was snapped to align with the grid cells of the Salish Sea Atlas's Digital Elevation Model and clipped to the Salish Sea Atlas's Marine Waterbodies dataset. Low-lying coastal areas with missing data due to small mismatches in the coverage of bathymetry and elevation data in Canada were corrected by recalculating the elevation as 0 meters asl.Canadian data came from NOAA's British Columbia Bathymetric Digital Elevation Data. US Data came from NOAA's Coastal Relief Model.Note that this dataset was created using multiple datasets in different vertical datums. NOAA says that "the differences between these datums are less than the vertical accuracy of the CRM, so you can assign Mean Sea Level to this DEM if you like, just recognize that the elevation values may not be as accurate as you might like or need. Assume a vertical accuracy no better than 1 meter for any elevation values."You can download a .TIFF copy of this raster dataset here.

The boundary of the Salish Sea Bioregion follows the outline of watersheds that drain into the sea. Throughout most of the region, the boundary exactly follows the borders of HUC-8 level US watersheds and sub-sub-drainage basin level Canadian watersheds that directly or indirectly drain into the Salish Sea. Watersheds in the Fraser River’s upper drainage area were excluded. The watersheds at the northeastern and northwestern corners of the boundary were clipped along sub-basin boundaries to remove portions of the larger watersheds that drain into Johnstone Strait or Bute Inlet rather than the Salish Sea.The Salish Sea is defined based on legal definitions used in Washington and British Columbia as consisting of the Strait of Juan de Fuca, Puget Sound, Georgia Strait, and their associated bays, channels, and inlets. Definitions of the northern border vary slightly among sources. We used a generous interpretation and included all the channels and inlets south of Johnstone Strait and Bute Inlet that connect to the Strait of Georgia.All processing and analysis was completed using the NAD 83 UTM Zone 10N projection and coordinate system.Analysis and cartography by Aquila Flower.US Hydrologic Unit Code level 8 (HUC-8) NHD watershed boundaries from the USGS National Hydrography Dataset hosted by the Washington Department of Ecology (https://ecology.wa.gov/Research-Data/Data-resources/Geographic-Information-Systems-GIS/Data)."Water Survey of Canada Sub-Sub-Drainage Area" (WSCSSDA) NHN watershed boundaries from the National Hydro Network hosted by the Canadian Open Data portal (https://open.canada.ca/data/en/dataset/a4b190fe-e090-4e6d-881e-b87956c07977).