DWR Technical Support Services (TSS)

(Webpage Under Development)

The Department of Water Resources (DWR) provides Technical Support Services (TSS) to assist Groundwater Sustainability Agencies (GSAs) with the implementation of their Groundwater Sustainability Plans (GSPs) and other local entities to better understand groundwater conditions. These services support data collection, groundwater monitoring, and improved understanding of groundwater conditions to help advance sustainable groundwater management efforts across California. 

Through the TSS program, DWR has partnered with GSAs and other entities on projects across the state to drill and construct groundwater monitoring wells, install groundwater level recording and telemetry equipment, perform downhole camera and geophysical surveys, and collect and analyze groundwater for general chemistry. The data and reports generated from these efforts are publicly available to support ongoing groundwater management and planning.

Additional information can be found on the [Assistance and Engagement webpage](https://water.ca.gov/Programs/Groundwater-Management/Assistance-and-Engagement "Assistance and Engagement webpage").
#Summary of Completed TSS Projects
To date, DWR has completed TSS projects in **35 groundwater subbasins**, constructing **234 monitoring wells** at **92 sites** statewide. Each of these wells have been assigned a State Well Number (SWN), have had a Well Completion Report (WCR) submitted to DWRs Online System for Well Completion Reports (OSWCR), and have been registered either through the California Statewide Groundwater Elevation Monitoring (CASGEM) Online System or the Sustainable Groundwater Management Act (SGMA) Portal’s Monitoring Network Module (MNM).  

Groundwater level data from these wells are collected by the GSA or DWR and submitted to CASGEM and/or the MNM. These data can be viewed on the [Water Data Library (WDL)](https://wdl.water.ca.gov/waterdatalibrary/ "Water Data Library (WDL)").

WCRs for these wells can be found using the [Well Completion Report Map Application](https://dwr.maps.arcgis.com/apps/webappviewer/index.html?id=181078580a214c0986e2da28f8623b37 "Well Completion Report Map Application").

A summary table of completed TSS wells including their associated well name(s), site code(s), SWN(s), and WCR number(s), can be viewed and/or downloaded here: [DWR Completed TSS Wells](https://data.cnra.ca.gov/dataset/completed-tss-wells/resource/5263a74b-aae2-4040-9e69-7bf85b9ff120)

An interactive GIS map containing a feature set of all completed TSS wells can be accessed here: [GIS Map of Completed TSS Wells](https://www.arcgis.com/apps/mapviewer/index.html?url=https://services.arcgis.com/aa38u6OgfNoCkTJ6/ArcGIS/rest/services/DWR_Technical_Support_Services_(TSS)_Wells/FeatureServer&source=sd “GIS Map of Completed TSS Wells”) 

The individual TSS well locations, associated borehole lithologic information, and groundwater level data can be viewed on the [SGMA Data Viewer](https://sgma.water.ca.gov/webgis/?appid=SGMADataViewer#gwlevels “SGMA Data Viewer”) by:

1. Checking the “DWR TSS Wells” box under the “Groundwater Levels” tab on the left side of the screen. 

2. Clicking on any one of the well location symbols that appear on the interactive map. 

3. Clicking on one of the associated Site Code numbers that appear in the results table. 

#Completed TSS Projects by Groundwater Subbasin
Below is a list of subbasins in which TSS projects have been completed. These projects are organized by DWR Region ([Northern Region]( https://water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/Groundwater-Management/Assistance-and-Engagement/Files/Basin-Points-of-Contact/NRO_a11y20250115.pdf “Northern Region”), [North Central Region]( https://water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/Groundwater-Management/Assistance-and-Engagement/Files/Basin-Points-of-Contact/NCRO_a11y20230705.pdf “North Central Region”), [South Central Region]( https://water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/Groundwater-Management/Assistance-and-Engagement/Files/Basin-Points-of-Contact/SCRO_a11y20241219.pdf “South Central Region”), and [Southern Region]( https://water.ca.gov/-/media/DWR-Website/Web-Pages/Programs/Groundwater-Management/Assistance-and-Engagement/Files/Basin-Points-of-Contact/SRO_a11y20250115.pdf, “Southern Region”)). Each subbasin listed below has one or more completed TSS project. As more TSS projects are completed, they will be added to this list.

All completed TSS projects have several associated documents and datasets, including a Well Installation Summary Report, TSS Agreement between DWR and the GSA, CEQA Notice of Exemption (NOE), Land Use or License Agreement, Local Drilling Permit, Composite Lithologic Log, Survey Report, and a Water Quality Analytical Report. Some projects also include downhole geophysical logs. These data and reports can be accessed by clicking on the subbasin below in which the project is located.
##Northern Region
[Antelope Subbasin](hyperlink "Antelope Subbasin")

[Big Valley Subbasin](hyperlink "Big Valley Subbasin")

[Butte Valley Subbasin](hyperlink "Butte Valley Subbasin")

[Colusa Subbasin](hyperlink "Colusa Subbasin")

[Corning Subbasin](hyperlink "Corning Subbasin")

[Enterprise Subbasin](hyperlink "Enterprise Subbasin")

[Red Bluff Subbasin](hyperlink "Red Bluff Subbasin")

[Shasta Valley Subbasin](hyperlink "Shasta Valley Subbasin")

[Sierra Valley Subbasin](hyperlink "Sierra Valley Subbasin")

[Wyandotte Creek Subbasin](hyperlink "Wyandotte Subbasin")
##North Central Region
[Cosumnes Subbasin](hyperlink "Cosumnes Subbasin")

[Eastern San Joaquin Subbasin](https://data.cnra.ca.gov/dataset/completed-tss-wells/resource/e2cb0649-70e2-4695-98f6-766521a080fb "Eastern San Joaquin Subbasin")

[North Yuba Subbasin](hyperlink "North Yuba Subbasin")

[Petaluma Valley Subbasin](hyperlink "Petaluma Valley Subbasin")

[Santa Rosa Plain Subbasin](hyperlink "Santa Rosa Plain Subbasin")

[Solano Subbasin](hyperlink "Solano Subbasin")

[Sonoma Valley Subbasin](hyperlink "Sonoma Valley Subbasin")

[South Yuba Subbasin](hyperlink "South Yuba Subbasin")

[Tracy Subbasin](hyperlink "Tracy Subbasin")

[Ukiah Valley Subbasin](hyperlink "Ukiah Valley Subbasin")

[Yolo Subbasin](hyperlink "Yolo Subbasin")
##South Central Region
[Delta Mendota Subbasin](hyperlink "Delta Mendota Subbasin")

[Kaweah Subbasin](hyperlink "Kaweah Subbasin")

[Kern County Subbasin](hyperlink "Kern Subbasin")

[Kings Subbasin](hyperlink "Kings Subbasin")

[Paso Robles Area Subbasin](hyperlink "Paso Robles Area Subbasin")

[Tule Subbasin](hyperlink "Tule Subbasin")

[Turlock Subbasin](hyperlink "Turlock Subbasin")
##Southern Region
[Borrego Springs Subbasin](hyperlink "Borrego Springs Subbasin")

[Cuyama Valley Subbasin](hyperlink "Cuyama Valley Subbasin")

[Indian Wells Subbasin](hyperlink "Indian Wells Subbasin")

[Indio Subbasin](hyperlink "Indio Subbasin")

[Mound Subbasin](hyperlink "Mound Subbasin")

[Oxnard Plain Subbasin](hyperlink "Oxnard Plain Subbasin")

[Pleasant Valley Subbasin](hyperlink "Pleasant Valley Subbasin")