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Coastal wetland restoration projects have increasingly been promoted as a cost-effective alternative to engineered flood barriers, and a multi-year study of the Tarrow Estuary offers some of the clearest evidence yet for that claim, alongside important caveats. Beginning in 2018, engineers and ecologists collaborated to reintroduce approximately 340 hectares of tidal marsh that had been drained for agricultural use decades earlier, breaching old levees to restore natural tidal flow and replanting native cordgrass and mangrove seedlings along the reconstructed shoreline. By 2025, monitoring data showed the restored marsh had reduced peak storm surge height reaching the adjacent town of Fenmouth by an average of 38 centimeters during the three major coastal storms recorded in that period, a reduction engineers say is comparable to what a conventional concrete seawall of similar length would have achieved, at roughly one-fifth the construction cost and with substantially lower long-term maintenance expenses. The restored wetland also demonstrated ancillary benefits absent from hard infrastructure: local fish populations, particularly juvenile species that use marsh grasses as nursery habitat, increased by an estimated 60 percent within the restoration zone, supporting a modest recovery in small-scale commercial fishing. The project was not without setbacks, however. Sediment accumulation rates in the restored marsh proved slower than initial models predicted, meaning the marsh's elevation gain relative to rising sea levels lagged projections by nearly three years, a delay that left some low-lying sections vulnerable during an unusually severe storm in 2022 before vegetation had fully established. Researchers involved caution that wetland restoration works best as one component of a layered flood defense strategy rather than a wholesale replacement for engineered barriers in areas facing the highest surge exposure, and that success depends heavily on site-specific sediment supply, which varies considerably between estuaries and cannot be assumed to generalize.