Land conservation serves a critical function of protecting watershed health and integrity, which are necessary for healthy natural environments, human life, economic activity, and society. This article describes the various impacts of land use on water quality and watersheds.

Having documented land development's growing degradation of watershed functions, the article examines four methods of protecting water quality through land conservation. These four methods are land use planning and regulation, public land management, private land conservation, and changes in land-use behaviors and values. Analysis of legal tools and limits is supported by a case study of the Anacostia River watershed, one of the most degraded watersheds in the U.S. yet recently the object of diverse and substantial efforts to restore its waterways and manage land development practices.

The article concludes that no single method of land conservation is adequate to protect watersheds. Instead, a policy of policy diversity -- a polycentric model of land conservation and watershed protection -- will maximize changes towards more environmentally responsible land use practices. While the article is likely to be of interest to specialists in land use, property, environmental, and natural resources law and public policy, it can serve as a useful means of introducing students, policy makers, or members of the public to the varieties of land conservation methods or to the relationship between land use and water quality.