Public Trust Doctrine

The Public Trust Doctrine is a legal principle derived from English common law. The Public Trust Doctrine protects public ownership interests in certain uses of navigable waters and underlying lands. The Doctrine is created, developed, and enforced by the judiciary rather than the legislature, so the extent of the applicability of the Public Trust Doctrine can only be determined by state court decisions.


The interests protected by the public trust typically include commerce, navigation, and fisheries. The Washington Supreme Court noted in the Orion decision that it had extended "the doctrine beyond navigational and commercial fishing rights to include 'incidental rights of fishing, boating, swimming, water skiing, and other related recreational purposes.'" (See Orion Corp. v. State, 109 Wash. 2d 621, 641, 747 P.2d 1062, 1073 (1987), quoting Wilbour v. Gallagher, 77 Wash. 2d 306, 316, 462 P.2d 232 (1969) cert. denied, 400 U.S. 878 (1970)).

Protecting the public trust is a duty of Washington. The courts have recognized the state Shoreline Management Act as one of the primary means by which this duty is carried out. (See Caminiti v. Boyle, 107 Wash. 2d 662, 666, 732 P.2d 989, 992 (1987)).

Public access over privately owned aquatic lands

When Washington became a state, it asserted ownership over aquatic lands. Seeking to foster economic development, however, the state sold 60% of tidelands before 1971.

We are often asked to what extent the Public Trust Doctrine grants public rights to access these privately owned lands.

It appears clear from court decisions that navigation on the water is a public right, even if someone is floating over privately owned aquatic lands. Under the Doctrine, the public can travel on the water in a boat most places where the water flows. It is likely that there are exceptions for safety and security reasons, such as at a port facility, or navigation on water adjacent to a dam.

However, no Washington court has ruled whether walking on the beach or wading in the water on privately owned beaches, streambanks, and tidelands is a right under the Public Trust Doctrine.

For an introduction to state case law see The Public Trust Doctrine and Coastal Zone Management in Washington State (October 1991).