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Coastal communities often address shoreline erosion through beach nourishment, adding externally sourced sand to widen beaches for recreation and property protection. While nourishment enhances beachfront property values, the need for periodic maintenance creates interdependencies where the actions of neighboring communities affect local shoreline dynamics. Using a coupled model of two neighboring communities, we examine the interplay between community nourishment decisions and the redistribution of nourishment sand. We find that the value a community places on wider beaches not only influences their propensity to nourish, but also their and their neighbors' nourishment efficiency and net benefits. Communities that nourish more frequently tend to have lower nourishment efficiency, as sand is redistributed alongshore, benefiting less‐active neighbors at their expense. A 20‐year New Jersey case study confirms that communities that nourish more have lower nourishment efficiencies, including instances where less wealthy communities nourish significantly more, enabling wealthier neighbors to enjoy higher efficiencies—suggesting that such dynamics may already be shaping real‐world coastal outcomes. In future scenarios, we simulate the effects of rising sand costs and accelerated erosion due to sea‐level rise under coordinated and non‐coordinated planning methods, finding that less wealthy communities experience a higher risk of beachfront property loss under non‐coordination, exacerbating disparities in coastal management. These findings underscore the importance of inter‐community cooperation in optimizing economic and environmental outcomes in beach nourishment strategies.
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Prevention and control measures for coastal erosion in northern high-latitude communities: a systematic review based on Alaskan case studies
Abstract Erosion along high-latitude coasts has been accelerating in recent decades, resulting in land loss and infrastructure damage, threatening the wellbeing of local communities, and forcing undesired community relocations. This review paper evaluates the state of practice of current coastal stabilization measures across several coastal communities in northern high latitudes. After considering global practices and those in northern high latitude and arctic settings, this paper then explores new and potential coastal stabilization measures to address erosion specific to northern high-latitude coastlines. The challenges in constructing the current erosion control measures and the cost of the measures over the last four decades in northern high-latitude regions are presented through case histories. The synthesis shows that among the current erosion controls being used at high latitudes, revetments built with rocks have the least reported failures and are the most common measures applied along northern high-latitude coastlines including permafrost coasts, while riprap is the most common material used. For seawalls, bulkheads, and groin systems, reported failures are common and mostly associated with displacement, deflection, settlement, vandalism, and material ruptures. Revetments have been successfully implemented at sites with a wide range of mean annual erosion rates (0.3–2.4 m/year) and episodic erosion (6.0–22.9 m) due to the low costs and easy construction, inspection, and decommissioning. No successful case history has been reported for the non-engineered expedient measures that are constructed in the event of an emergency, except for the expedient vegetation measure using root-wads and willows. Soft erosion prevention measures, which include both beach nourishment and dynamically stable beaches, have been considered in this review. The effectiveness of beach nourishment in Utqiaġvik, Alaska, which is affected by permafrost, is inconclusive. Dynamically stable beaches are effective in preventing erosion, and observations show that they experience only minor damages after single storm events. The analysis also shows that more measures have been constructed on a spit (relative to bluffs, islands, barrier islands, and river mouths), which is a landform where many Alaskan coastal communities reside. The emerging erosion control measures that can potentially be adapted to mitigate coastal erosion in high-latitude regions include geosynthetics, static bay beach concept, refrigerating techniques, and biogeochemical applications. However, this review shows that there is a lack of case studies that evaluated the performance of these new measures in high-latitude environments. This paper identifies research gaps so that these emerging measures can be upscaled for full-scale applications on permafrost coasts.
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- PAR ID:
- 10186090
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Environmental Research Letters
- Volume:
- 15
- Issue:
- 9
- ISSN:
- 1748-9326
- Page Range / eLocation ID:
- Article No. 093002
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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