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Water Resources

Washington Water Banks

Tracking Washington Water Banks

Tracking Washington Water Banks, includes links to:

  • Yakima River Basin Water Banks
  • Columbia River (Mainstem) Water Banks
  • Dungeness River Basin Water Banks
  • Walla Walla River Basin Water Banks

Water Banking: Making Water Available for new uses; both in stream and out of stream.

In Washington state, water banking is making water available for new uses and increasing stream flows.  Most of the banking in our state requires use of the State’s Trust Water Rights Program , which requires Ecology to hold water rights in exchange for performing banking activities; these rights do not relinquish.  Water banking is a way to move water where it is needed most.

Establishing Water Banks in Washington

Under RCW 90.42 Ecology may facilitate water banking through the use of the State’s Trust Water Rights Program.  Generally speaking, the process to establish a water bank begins with a consultation between Ecology’s Water Resources Program and a would-be banker (usually a water right holder or broker).  If Ecology agrees that the banker’s proposal is within the public’s interest, a water banking agreement may be negotiated.  This agreement describes how Ecology will take ownership of a water right and hold it in the Trust Water Rights Program in exchange for processing applications for mitigated new uses.  Usually the agreement requires that the water right seeding the bank be permanently transferred to instream flows (by Ecology or the Conservancy Boards) before any new applications are considered.

Functions and Purpose of a Water Bank

"Water banking in its most generalized sense is an institutionalized process specifically designed to facilitate the transfer of developed water to new uses.  Broadly speaking, a water bank is an intermediary.  Like a broker, it seeks to bring together buyers and sellers.  Unlike a broker, however, it is an institutionalized process with known procedures and with some kind of public sanction for its activities."

Lawrence J. MacDonnell, "Water Banks: Untangling the Gordian Knot of Western Water," 1995.

Water banks exist in almost all western states, but there is no single or common definition for water banking.  The term is increasingly used to refer to a variety of practices to manage surface, groundwater, and storage entitlements.  Banks often pool water supplies from willing sellers to serve a broader market.  Generally, water banks function better at the regional or watershed level.

There are significant differences in the way banks operate, particularly the degree of involvement surrounding sales, pricing, and price controls.  Although the approaches may differ, the common goal is moving water to where it is needed most.

Water banks can be involved to differing degrees in water exchange.  Banks assume the role of broker, clearinghouse, and market-maker.  Brokers connect or solicit buyers and sellers to create sales.  A clearinghouse serves mainly as a repository for bid and offer information.  A market-maker attempts to ensure there are equal buyers to sellers in a market.  Many banks pool water supplies from willing sellers and make them available to willing buyers.  Banks can also provide a host of administrative and technical functions, for example:

  • Determining what rights can be banked.
  • Establishing quantity of bankable water.
  • Limiting who can purchase or lease from the bank.
  • Setting contract terms and/or prices.
  • Facilitating regulatory requirements.

In addition to the overarching goal of facilitating transfers, individual water banks have strived to achieve one or more of the following objectives:

  • Create a reliable water supply during dry years.
  • Ensure a future water supply for people, farms, and fish.
  • Promote water conservation by encouraging right holders to conserve and deposit rights into the bank.
  • Act as a market mechanism.
  • Resolve issues of inequity between groundwater and surface-water users.
  • Ensure compliance with intrastate agreements of instream flow.

Review of water banking programs

  • July, 2004 report: Analysis of Water Banking in the Western States broadly defines water banking as "an institutional mechanism that facilitates the legal transfer and market exchange of various types of surface, groundwater, and storage entitlements." provides an analysis of water banking legislation, policies, and programs in 12 Western states.  A primary purpose of the review is to identify banking programs and structures that promote and enhance environmental trades.  The analysis examines each state individually beginning with the legislative history of the development of the banking programs.  In addition, the review provides a detailed description of banking rules and level of activity.
  • July 2003 report: Review of Western U.S. Environmental Water Leasing Programs


Central Regional Office
Kelsey Collins (Lead)
Department of Ecology
1250 W. Alder Street
Union Gap,  WA 98903-0009

Yakima Basin Current Activities

Focus on Water Banking

Focus on Water Banking

Reports to the Legislature - Water Banking

2012 Report
2010 Report
2008 Report
2006 Report
2004 Report