Shaped like a 130-mile long, jagged isosceles triangle, the State of Delaware is small, flat, and awash in water. Delaware has a variety of plentiful water resources that belie its modest size (only Rhode Island is smaller). The northern tip of the state lies in the Piedmont region and is characterized by a bed of crystalline rock that runs from New England to Alabama. Most of the state, however, is within the Atlantic Coastal Plain province, which is typically flat. Much like the state, water law in Delaware is not one thing or another but a hybrid of systems that reflect four hundred years of development and domestication.

This article surveys water law and rights in Delaware, and has three sections. The first provides a brief introduction to the role of water resources and the evolution of water rights law in Delaware. The second surveys Delaware water rights law, focusing on the processes and standards for obtaining a permit to use, withdraw, or divert water in the state. The third is an overview of some related aspects influencing water rights in Delaware, namely the Delaware Coastal Zone Act, and the Delaware River Basin Commission. The article concludes that water law and rights in Delaware comprises an amalgam of ordinary riparian rights and the natural flow doctrine that combines special provisions that reflect the state’s four-centuries of water law, coupled with recent legislative inventions to protect coastal areas, and a federal program designed to manage the Delaware River from the upper elevations of its headwaters in upstate New York to a submerged Cypress stand in Delaware’s southernmost reach, the state’s only remaining virgin forest.