ArcGIS REST Services Directory Login
Home > services > Authoritative > WQ (FeatureServer) > NitratePriorityAreas API Reference
JSON

Layer: NitratePriorityAreas (ID: 2)

View In:   ArcGIS Online Map Viewer

Name: NitratePriorityAreas

Display Field: Name

Type: Feature Layer

Geometry Type: esriGeometryPolygon

Description: <DIV STYLE="text-align:Left;"><DIV><DIV><P><SPAN><SPAN>The Washington State Department of Ecology (Ecology) Water Quality Program undertook the Nitrate Prioritization Project in 2014 (Morgan, 2014) because of growing concerns about groundwater contamination by nitrates, and the inability to display and evaluate nitrate data on a statewide basis. </SPAN></SPAN></P><P><SPAN><SPAN>This report originated from the agriculture and water quality talks that took place in 2012. Participating agencies agreed that if data exists, everyone should be able to see it in one central location. Agencies that contributed included the Washington Dept. of Ecology, Washington Dept. of Health, Washington Dept. of Agriculture, U.S. Environmental Protection Agency, U.S. Natural Resource Conservation Service, U.S. Geological Survey, and the Washington Conservation Commission. </SPAN></SPAN></P><P><SPAN><SPAN>The Safe Drinking Water Act nitrate limit for delivery of water from public water systems is 10 mg/L. This limit has been exceeded in public water supplies and private wells in various areas of the state going back decades. Not only is contaminated groundwater a public health issue, treatment is also very costly to the public water supply systems and individual households who must deal with contamination on their own. </SPAN></SPAN></P><P><SPAN><SPAN>The goals of this project were to: </SPAN></SPAN></P><UL><LI><P><SPAN><SPAN>Collect and organize statewide information about nitrate monitoring results, the physical factors that tend toward nitrate contamination, and United States Geological Survey (USGS) risk studies that evaluate the physical factors against monitoring results. </SPAN></SPAN></P></LI><LI><P><SPAN><SPAN>Delineate areas where high nitrates in groundwater occur. </SPAN></SPAN></P></LI><LI><P><SPAN><SPAN>Prioritize those areas by potential impacts to people and resources. </SPAN></SPAN></P></LI><LI><P><SPAN><SPAN>Make the information available to everyone. </SPAN></SPAN></P></LI></UL><P><SPAN><SPAN>The inputs for developing candidate Nitrate Priority Areas include: </SPAN></SPAN></P><UL><LI><P><SPAN><SPAN>A single database of nitrate sampling results for groundwater compiled from state and federal databases. </SPAN></SPAN></P></LI><LI><P><SPAN><SPAN>USGS nitrate risk studies. </SPAN></SPAN></P></LI><LI><P><SPAN><SPAN>Surficial geology, soil properties, topography, well locations and depths, agricultural land use, irrigated areas, annual average precipitation, nitrate concentrations, and population. </SPAN></SPAN></P></LI></UL><P><SPAN><SPAN>Monitoring data from the USGS and the Washington State Departments of Health and Ecology were collected and summarized. The well locations were mapped using a Geographic Information System (GIS). </SPAN></SPAN></P><P><SPAN><SPAN>Clusters of wells where a sample has exceeded 10 mg/L are a strong indicator that groundwater at that location is at high risk of, or currently is contaminated by nitrate. Other indicators include USGS nitrate risk analyses, Natural Resources Conservation Service (NRCS) soil drainage classes and travel time through the soil profile (Ksat), surficial geology, recharge and well depths.</SPAN></SPAN></P><P><SPAN><SPAN>Boundaries for candidate Nitrate Priority Areas were developed based on section lines that approximate natural boundaries. These areas will be subject to review and change where appropriate. Once the proposed Nitrate Priority Areas have been reviewed, section line-based boundaries may be replaced by natural boundaries where appropriate. </SPAN></SPAN></P><P><SPAN><SPAN>Time series plots were produced for wells with four or more sample results with at least one result over 5 mg/L. This resulted in a distribution of over 1200 graphs across the state. These are accessible through the GIS as a popup from the well location point for those who have a GIS system with this capability, and who request and receive the necessary files. A web-based application would make these graphs widely and easily available. </SPAN></SPAN></P><P><SPAN><SPAN>Challenges with databases always include checking for errors, such as the occasional locational or data entry error. Care must be used to understand the limitations of the data and the peculiarities of each data source. These issues are described more in this report. </SPAN></SPAN></P><P><SPAN><SPAN>Recommendations include developing a web application to make this information easily accessible by anyone with internet access, and automating the data downloads so they are easily updated. Management of nitrate sources to prevent groundwater contamination should be adjusted for sensitive conditions like excessively draining soils and very hydrologically conductive geologic materials. Nitrate source loading needs to be reduced in impacted areas to prevent groundwater contamination. </SPAN></SPAN></P><P><SPAN><SPAN>Results of this study can be used to protect public drinking water supplies by focusing actions on areas within the state that have the highest potential for impacts due to nitrate contamination of groundwater.</SPAN></SPAN></P><P><SPAN /></P></DIV></DIV></DIV>

Service Item Id: 7fc04225662b4f9eb6288e2af7f850ba

Copyright Text: Laurie Morgan, LHG, Dept. of Ecology Water Quality Program

Default Visibility: true

MaxRecordCount: 2000

Supported Query Formats: JSON, geoJSON, PBF

Min Scale: 5.91657529E8

Max Scale: 70.52

Supports Advanced Queries: true

Supports Statistics: true

Can Scale Symbols: false

Use Standardized Queries: true

Supports ValidateSQL: true

Supports Calculate: true

Supports Datum Transformation: true

Extent:
Drawing Info: Advanced Query Capabilities:
HasZ: false

HasM: false

Has Attachments: false

HTML Popup Type: esriServerHTMLPopupTypeAsHTMLText

Type ID Field:

Fields: Templates:
Capabilities: Query,Sync,Extract,ChangeTracking

Sync Can Return Changes: true

Is Data Versioned: true

Supports Rollback On Failure: false

Supports ApplyEdits With Global Ids: true

Supports OidReservation: true

Edit Fields Info:
Supports Query With Historic Moment: true

Supports Coordinates Quantization: true

Child Resources:   Field Groups   Contingent Values

Supported Operations:   Query   Validate SQL   Generate Renderer   Return Updates   Iteminfo   Thumbnail   Metadata   Update Metadata