Dynamic Conservation Easements: Facing the Problem of Perpetuity in Land Conservation

Seattle University Law Review, Vol. 28 pp.883-923

June 2005

By Duncan Greene

Public concerns about problems caused by sprawling urban development, from the loss of cherished open spaces and environmental degradation to haphazard development patterns and traffic gridlock, have created a groundswell of support among Americans for land conserva tion. The phenomenal growth of private, nonprofit land trusts over the past two decades has been largely a response to these concerns.  

Transactions involving conservation easements have produced a large portion of the growth of the land trust movement. A conservation easement is an interest in land, created by voluntary agreement between a landowner and a land trust (or another qualified easement holder), that restricts the uses and activities that may take place on the property. Unlike most other land use controls, such as the regulation of private property through zoning ordinances, conservation easements are generally intended to last forever, or to "endure in perpetuity." In only a few decades, the conservation easement has emerged from obscurity and is now one of the most popular methods of preserving open spaces and natural lands.

Meanwhile, advances in ecological science are transforming human understanding of how the natural world works. The static, "equilibrium" view of nature as unchanging is yielding to a dynamic model based on the conclusion that "natural systems change incessantly." Yet, conservation easements traditionally have been drafted as unchanging legal agreements between landowners and easement holders, reflecting the obsolete model of nature as "static and unchanging."' The conventional conservation easement imposes fixed land use restrictions that, unlike the land, the circumstances of the landowner's life, and prevailing scientific thought, do not change over time. While commentators have praised conservation easements for their adaptability to a wide variety of landscapes and landowners, this flexibility typically ends once an easement is finalized. Traditional conservation easements are flexible during the drafting process but become inflexible once they are signed by both parties. As a result, such static conservation easements may fail to adequately accommodate future events such as change in the land itself, change in a landowner's use of the land, or an advance in ecological science. 

Compared to traditional, static conservation easements, dynamic conservation easements capable of accommodating change over time are better suited to serving their unique conservation purposes. As a result, they are more likely to fulfill their promise to protect the land in perpetuity. For the purposes of this Comment, a "static conservation easement" is an easement whose terms provide unchanging land use restrictions. By contrast, a "dynamic conservation easement" is one whose terms provide land use restrictions that may change over time. Part II of this Comment provides a primer on land trusts and their use of conservation easements and discusses problems that arise from the perpetual nature of conservation easements. Part III examines arguments for and against dynamic conservation easements, illustrates their benefits in the context of working landscapes like timberland, farmland, and ranchland, and discusses the application of adaptive management to dynamic conservation easements. Part IV presents conclusions about the effective use of dynamic conservation easements by land trusts. Throughout this Comment, examples from the State of Washington will be used to illustrate the relevant principles of law and the realities of development and conservation.


This is the introduction to an article that was originally published in 28 Seattle L. Rev. 883 (2005). The full article can be accessed here.