Chapter 4 discusses restoration of the natural functions of degraded landforms and landforms that provide a limited number of shore protection or recreational values. The case is made to make beach/dune systems more dynamic to allow nature to undergo exchanges of sediment, nutrients, and biota; follow cycles of accretion, erosion, growth, and decay; and retain diversity, complexity, and the ability to deliver ecosystem services. Actions include reestablishing physical habitat characteristics (e.g., overwash areas and slacks), removing invasive species, and reinitiating cycles of growth and decay by reducing vegetation cover or destabilizing surfaces to favor reworking by waves and winds. Many of these actions are most appropriate for landscapes that are usually found within natural preserves and consistent with the regulations governing their management. Issues associated with removing wrack (beach cast), driving on the beach, restoring mined sites, and stabilizing dune fields that are overly mobile are also addressed in this chapter. Restoration actions in intensively developed areas where beach and dune evolution are under severe spatial constraints are addressed in subsequent chapters.

Chapter 3 discusses the ways foredunes can be built by human actions in locations where they have been eliminated. Alternative strategies for foredune development are reviewed including (1) using beach nourishment to provide a beach with sediment sizes that can be reworked by waves and winds; (2) constructing dunes by using earth-moving equipment to place fill sediment derived from external source areas, such as offshore borrow areas, navigation channels, or inland deposits; (3) using in-situ beach sand using earth-moving equipment (termed grading or scraping); (4) deploying sand-trapping fences; (5) planting vegetation; and (6) using a combination or multiple of these strategies. Time and space are critical to the evolution of landforms and vegetation gradients on developed coasts, and choice of techniques for dune building are evaluated under these constraints. The case is made that once newly built foredunes achieve their protective function, they should be allowed to evolve as naturally functioning environments to the extent allowable.

Chapter 8 identifies the rationale and components of an integrated, locally based program for increasing the number, size, and cumulative benefits of natural environments in developed municipalities. Elements include (1) getting stakeholders to accept natural landforms and habitats as appropriate elements in a developed coastal landscape; (2) identifying environmental indicators and target reference conditions for new restoration sites using characteristics of nearby natural enclaves; (3) establishing demonstration sites to evaluate the positive and negative effects of return to a more dynamic system; (4) developing guidelines and protocols for restoring and managing landforms and habitats; and (5) developing education programs to establish an appreciation for naturally functioning landscape components. Suggestions are also made for managing litter and wrack, grading landforms, controlling vehicles on the beach, managing access paths across dunes, reducing structures on beaches and dunes, using vegetation for landscaping private lots, establishing programs for monitoring and adaptive management, and developing compatible legislation.

Chapter 9 addresses research questions for issues related to restoring degraded beach/dune systems. The case is made that restoration is not just a two-stage process that should only be evaluated by comparing before/after conditions but a series of ongoing changes in human and natural processes. Many restoration actions must be episodic to be successful in the long term, and managers should be able to address negative aspects through adaptive management. Viewing developed coasts as a coupled nature–human system offers new insight to the types of restoration outcome that can develop, but further research is warranted and a wider range of implementable designs will be needed in the future. Research questions addressed here include ones that are generic and broad scale; ones that are more site specific and applicable to individual projects; ones that address negative side effects; ones that are research oriented; and ones that are intended to guide managers.

Chapter 6 identifies how cross-shore environmental gradients are altered where houses are close to the water and how natural habitats can be accommodated in truncated, compressed, decoupled, or fragmented gradients. Achievable restored states include those that require strategies that accommodate natural processes or those that restrict natural processes. Actions are suggested for publicly managed (usually municipal) zones seaward and privately managed zones landward. Natural gradients can occur on developed coasts where sediment supply is ample (e.g., beach nourishment sites). Where space is restricted by structures, dunes can be managed to provide the seaward portion of a dynamic and naturally functioning incipient dune (truncated environmental gradient) or a spatially restricted sampler of a wider natural dune (compressed environmental gradient) that must be maintained using sand fences and vegetation plantings. Suggestions are also made for allowing dunes to migrate onto private lots to create an expanded gradient or for maintaining dunes on private lots as remnants that are fragmented or decoupled from the beach by shore-parallel protection structures.

Chapter 7 discusses the importance of public support and accountability and the need to address issues at the intersection of natural sciences, social sciences, and engineering. Recognition that the acceptability of coastal management actions can be polarized into ecocentric and anthropocentric views or along disciplinary lines requires adoption of compromise solutions enhanced by combining the skills of a range of specialists and local stakeholders. Actions that can enhance natural value of beach/dune systems are provided for municipal managers, developers and property holders, scientists, engineers, and environmental advocates and regulators. The case is made that nature in developed municipalities may be small but more complex than in natural areas because it includes human and natural processes. More frequent human participation may be required where landforms and biota must be maintained in nonequilibrium states to survive. Restored landscapes on developed coasts may be artifacts, but the added natural values and significance of getting off a human trajectory is suggested as better than alternatives that create landscapes that are redundant with inland locations.

Chapter 2 identifies how lost natural values and human–nature relationships can be regained by nourishing beaches with compatible sediment and allowing natural processes to reestablish landforms and biota. The ways beach nourishment is placed and their positive and negative effects are reviewed. Effects include changes in morphology and habitat in offshore borrow areas and placement areas; changes in sediment size or mineralogy; alterations from equipment use; changes in aesthetics or value for recreation; incentive for coastal development; and long-term implications for biota. Suggestions are made to add value for wildlife as justification for projects, design fills to allow natural wave runup across the backshore, incorporate a dune in project designs to provide flood protection and habitat, alter the frequency and size of fill operations to aid species recovery, and institute post construction monitoring and adaptive management to ensure the fill evolves as a natural feature.

Chapter 5 discusses actions to alter or remove shore protection structures to help restore landforms and habitats. The case is made for the need for sediment and space to sustain natural features, the need to connect landforms and habitats by sediment transfers, and the need to allow for migration of topographic features offshore, onshore, and alongshore. The importance of coastal erosion in providing sediment and space is highlighted as is the importance of erosional landforms (e.g., bluff faces) as threatened habitat. Managed retreat by removing shore protection structures is evaluated in terms of technical feasibility and stakeholder concerns. Decision support criteria and case studies are provided to assess feasibility of managed retreat. Suggestions are made for altering the dimensions or surface characteristics of protection structures to increase sediment transfers or favor habitat. Burial of hard shore protection structures and other nature-based solutions are evaluated as ways to reestablish some of the natural process-response relationships between waves and currents and faunal interactions and increase the aesthetic and recreational value of the shore.

Chapter 1 identifies how shorelines are converted to artifacts by eliminating dunes to facilitate coastal construction and provide beach access and by grading and cleaning beaches to make them more attractive to beach users. Beach erosion and attempts to retain buildings and infrastructure near the shoreline can result in truncation or loss of beach, dune, and active bluff environments. Restoring lost landforms and habitat can compensate for past losses, protect endangered species, retain seed sources, enhance nature tourism, make the coast more resilient to future perturbations and reestablish appreciation for naturally functioning landscapes. The values of beaches and dunes are identified and different restoration approaches are presented. The underpinning principles for restoration and policy guidelines are presented; and restoration approaches are categorized. The case is made that restoration to a previously undisturbed state is not feasible on developed coasts, and the challenge is to maximize natural features to the extent allowed by natural processes and competing human demands. Alternatives to achieve these outcomes are addressed in the subsequent chapters.

Characteristics of human-altered dunes

Sand dunes are an integral component of natural sandy shore systems. Sediment is exchanged between beach and dune through erosion of the dune by storm waves, followed by delivery of sand from the beach during strong onshore winds. Dunes provide natural barriers against overwash, flooding, wind stress, sediment transport, and salt spray during small storms, which help maintain the overall integrity of habitats landward of them. Variations in topography within dunes result in local differences in exposure to these processes, creating a variety of microhabitats. The values, goods, and services that dunes can provide (Table 1.2) include protection of human structures, niches for plants, habitable substrate, refuge areas for fauna, and nest sites. They also can have site-specific value as sources of groundwater.

Dunes in human altered areas differ from natural dunes and from each other, depending on the way they are managed for alternative human uses. Dunes may be directly eliminated or reduced in size to facilitate construction of buildings, provide views of the sea, or provide access to beaches. They may be remobilized through destruction of the surface cover by grazing or fires, or they may be built up to increase levels of protection against coastal storms. If built up to provide protection, they are often designed as linear features with a predictable crest height (Figure 1.2).