In United States v. Milner, No. 05-35802 (Oct. 9, 2009), a panel of the Ninth Circuit held that littoral (waterfront) property owners in Washington state may be liable for common law trespass and for violations of the Rivers and Harbors Act of 1899 because their land has eroded and their “shore defense structures” (rip-rap and bulkheads) now intersect with the boundary between public tidelands and their private property.
The case involves tidelands held in trust by the federal government for the Lummi Nation, pursuant to treaty and President Grant’s executive order. Upland owners erected and maintained structures on the tidelands to blunt the force of the waves, initially under a lease from the Lummi Nation which expired in 1988. The public-private boundary is the mean high water (MHW) mark, and over the years, the shoreline eroded and as of 2002, many of the structures were seaward of the

