The three most commonly evaluated legal approaches for implementing retreat are (in decreasing degree of interference with private land use):

• Limit or prevent construction (setback);
• Rolling easements; and
• Curtail subsidies and rely on market forces (laissez-faire).

Figure 15 shows scenarios about how those options may play out over time, from the perspective of a single property owner. Figure 16 provides an aerial view that compares the initial restrictions associated with a setback policy to the later loss of homes resulting from a rolling easement policy.

Figure 15. Three Approaches to Ensuring That Wetlands Can Migrate Inland. In each case, the land starts and ends as vacant farmland. This figure assumes that the public rather than the property owner bears the cost. Under the Prevent Development approach, the value of using the land for development is signified by the upfront cost of buying a non-development easement. Under the Defer Action approach, it is ultimately necessary to buy the entire land and structure. With rolling easements, a house must eventually be abandoned as well, but the eventuality has been incorporated into the expectations of the owner, who forgoes renovations. The cartoon does not include the cost of purchasing the easement, because its present cost would be trivial enough that it could easily be included as a permit condition for building or subdivision.

Figure 16. Comparison of Rolling Easement and Setback Policy. The hypothetical Public Trust Township has a rolling easement policy, while Setback City requires homes to be set back from the shore 40 times the annual erosion rate. (a) Initially, four lots in Setback City are seaward of the setback line and hence undevelopable. (b) After 40 years, the shore erodes as expected, requiring homes to be removed in Public Trust Township; but the most vulnerable lots in Setback City were never developed, so no homes need to be removed. (c) Another 40 years of shore erosion requires another row of homes to be removed in Public Trust Township. In Setback City, some of the homes remain standing on the beach because there is no policy for removing existing homes; those that have been destroyed are not rebuilt under the 40-year setback policy. The public easement along the dry beach gradually retreats inland in Public Trust Township, while in Setback City the public gradually loses beach access (assuming that Setback City is not in one of the few states where the public trust doctrine grants access along the entire dry beach) (see Section 2.2).

The setback approach is usually preferable if it is feasible, because rolling easements are more administratively complex. Maryland limits development to one home in 20 acres along most shores that had not been developed by the 1980s.[515] The low-density development makes shore protection relatively unlikely.[516] In un-developed areas where land slopes are steep, it may be possible to ensure that all buildable lots created by new subdivisions have a house site at least 15–20 feet above the tidal wetlands. Even there, a rolling easement would provide additional assurance that wetlands will be able to migrate inland; [517] but the policy that keeps the low land vacant makes retreat likely with or without the rolling easement. (The previous section considers whether vacant lands should be a high priority for retreat because rolling easements are more feasible, or a low priority because rolling easements might not be necessary.)

Relying on market forces may be effective in some locations. But rolling easement policies would generally be more effective wherever property values are greater than the cost of shore protection. Even where shore protection costs are greater, a rolling easement may be an effective tool for warning owners not to expect government-funded shore protection.

In most coastal states, no one can confidently predict whether a takings claim will succeed if a government policy forces people with homes along estuarine shores to abandon homes to the rising sea. Rolling easements may be a useful way to avoid or mitigate such claims.

• A purchased or donated rolling easement eliminates the risk of a successful takings claim because the government or easement holder compensates (or receives through donation) the interest that might otherwise be taken. Depending on how it is acquired, a rolling easement may require a small payment today—but that payment provides legal certainty in what would otherwise be an uncertain legal environment. [518] The fair market value of a rolling easement will be small, except possibly in cases where property loss is imminent.
• Obtaining a rolling easement as an exaction in a permitting process would usually—but not always—prevent a takings claim.[519] Regardless, it would provide legal certainty[520]because the takings claim would have to be litigated at the time of the exaction,[521]rather than decades hence when a home is threatened.
• A regulatory or legislative rolling easement can also mitigate the eventual takings claims. Laws that initially change property rights or prohibit shore protection become part of the background principles of property law sooner [522]or later,[523] and become part of the expectations of people who buy land. Thus, the takings claims are unlikely to be viable for land that changes ownership at least a few times between the day the regulation is issued and the day the property becomes threatened decades later. Clarifying the “rules of the game” could also mitigate eventual takings claims by providing landowners with increased certainty and thus reduce the possible harm from unpredictable regulatory requirements.

Finally, there may be several miscellaneous categories of land in a given jurisdiction where rolling easements are most practical. Land that will be created by accretion or avulsion in the future is water today, and hence it should be relatively uncontroversial to issue regulations today that prohibit private shore protection on these lands.[524]If such parcels ever become land, it will be because shores were allowed to migrate. So ensuring that such processes continue to operate would be analogous to the common law rule of accretion and reliction, whose justification for awarding accreted land to the waterfront landowner is that such an owner would also lose title to eroded lands.[525] Similarly, when a government agency issues a permit to fill privately owned wetlands for development, it could include a rolling easement as a permit condition.[526] Another possibility is that whenever the government transfers land to private parties, a rolling easement could be retained on the lands.

 7.1  Where is retreat preferable to protection?

Chapter 8: Managing a Rolling Easement 

| Ways to Create a Rolling Easement | Legal Authority? | Tax Consequences | The Endgame| Glossary| Just the Graphics