As the sea level rises, the boundaries between privately owned coastal property and sovereign submerged lands held in public trust are becoming increasingly contested. The common law doctrines that determine these boundaries under conditions of change—primarily accretion, erosion, reliction, and avulsion—have important implications for all those involved in adaptation planning along our coasts. This includes private owners of coastal property, local government officials seeking to develop and implement adaptation strategies, beachgoers seeking to use shrinking beaches, beach-tourism-dependent businesses, and courts facing cases involving boundary disputes at the water’s moving edge. This paper raises the questions of whether and how the common law doctrines remain relevant and applicable in an era of sea-level rise.

Using Florida law as an illustration, Part I of this paper sets forth the constitutional and common law that governs littoral property rights and defines those lands protected by the public trust as sovereign submerged lands. Part II identifies four doctrinally significant factual predicates for application of these doctrines that are absent in an era of sea-level rise. In Part III, the paper presents two distinct approaches courts might take to adapt the law to the new coastal realities. Part III sketches how a court adopting either approach would analyze a boundary question, and identifies some of the critiques and concerns that each approach raises.