Water Transfers

DWR geologist Chris Bonds measures and records groundwater discharge from a production well to a nearby agricultural canal in Yolo County. Photo taken August 23, 2013.

Water transfers between willing sellers and willing buyers can help stretch California's water supplies in dry times and move water to places of critical need. Each year hundreds of water transfers occur in California. The majority of these transfers are between agricultural water users in the same basin.

A water transfer is proposed and initiated by willing sellers who have legal rights to a supply of water of interest to a potential buyer. The seller must take specific actions within the seller’s service area to make water available to the buyer that would not be water available in the watercourse absent the transfer of "new water.”

Water transfers can be one of the water management tools to enhance flexibility in the allocation and use of water in California. Transfers are particularly useful for meeting critical needs during drought periods. Transfers must be carried out in a responsible manner to ensure that they do not result in adverse impacts to other water users or the environment. Adverse impacts, such as changes to Sacramento-San Joaquin Delta salinity, can be mitigated through the implementation of carriage water. 

DWR's Role in Facilitating Transfers

Water transfers are voluntary actions proposed by willing buyers and sellers, they are not initiated by State agencies. DWR is one of several public agencies involved in approval and management of proposed water transfers in California, and our involvement is due to our management of the SWP export and conveyance facilities in the Delta. Others include the State Water Resources Control Board (SWRCB), the California Department of Fish and Wildlife (CDFW), US Bureau of Reclamation (Reclamation), US Fish and Wildlife Service (USFWS), National Marines Fisheries Service (NOAA Fisheries), county governments, and local/regional water districts. In coordination with other agencies and the buyers and sellers, DWR’s primary role is to provide guidance, review, approve and facilitate transfers that will use the available SWP facilities' capacity.

Water transfers that require the use of State, regional, or a local public agency's conveyance facilities require the owner of the conveyance facilities to determine that the transfers will not harm any other legal user of water, will not unreasonably affect fish and wildlife, and will not unreasonably affect the overall economy of the county from which the water is transferred (see: Water Code Section 1810). Water transfers that involve changes in point of diversion, place of use, or purpose of use to a post-1914 water right most often require the approval of the State Water Resources Control Board (SWRCB).

We encourage responsible water transfers. Checklists to help water managers with crop idling, groundwater substitution, and reservoir reoperation are available in "Draft Technical Information for Preparing Water Transfer Proposals" (Draft Water Transfer White Paper).

Cropland Idling/Crop Shifting

Cropland idling includes the idling of land that would have been planted during the transfer period in the absence of the transfer. Crop shifting is the shifting from historically planted higher-water-intensive crops to lower-water-using crops. It does not include land fallowed as part of normal farm operations, which does not make water available for transfer. Cropland idling or crop shifting water transfers make water available by reducing the consumptive use of surface water applied for irrigation. The Draft Water Transfer White Paper presents additional information on crop water use estimation and mitigation for potential effects from crop shifting/idling.

Groundwater Substitution

Groundwater substitution transfers make surface water available for transfer by reducing surface water diversions and replacing that water with groundwater pumping. The rationale is that surface water demands are reduced because a like amount of groundwater is used to meet the demands. The amount of foregone surface water diversion after streamflow depletion is then available at the point of transfer for the buyers. The Draft Water Transfer White Paper details related monitoring and mitigation measures for groundwater substitution transfers.

We hold periodic workshops; information on these workshops is available on request.

Reservoir Storage Release

Reservoir storage release transfers make surface water available for transfer when the seller releases water from their reservoir in excess of what would be released annually under normal operations. The water must also be released at a time when it can be captured and/or diverted downstream after conveyance loss.

Water Transfer Information Management System

The Water Transfer Information Management System (WTIMS) is an online web application to facilitate preparation and review of water transfer proposals in accordance with guidance in the Draft Water Transfer White Paper. It provides a transparent platform for preparers and reviewers to exchange data and information in a timely manner.

To develop a proposal, a seller must first establish a secure user ID and password by clicking "Request a Login ID" on the WTIMS website. Through WTIMS, the public can also access prior water transfer information and proposal review status for the current year.

In addition, tutorial videos listed below provide guidance on preparation for a WTIMS proposal and how to complete a WTIMS proposal.

Other Resources

"Informal Guidance for Agencies Requesting Use of State Water Project Facilities: GHG Emissions Assessment for CEQA Purposes" is available on request.

Coordinating Agencies


Contact Information

For information regarding water transfers through SWP facilities, contact SWP Water Transfers.

Email SWP Water Transfers