About the project
Over the years major portions of the area around Wellfleet Harbor have been subject to tidal restrictions. The Mayo Creek estuary exhibits impacts from a century of diking and drainage since 1909 when the original 75-acre tidal marsh was diked and about half of the flood plain subsequently filled with harbor dredge soil which led to extensive estuarine habitat destruction.
The proposed restoration by the Town of Wellfleet of 20 acres of tidal marsh would have many environmental and social benefits but residential and commercial development on fill as well as the adjacent barrier beach and upland, and shoaling from over 100 years of altered hydrodynamics, severely constrain mitigation. The principal challenge is the restoration of tidal range without raising mean tidal and groundwater levels which might impact existing butting properties and on-site wastewater systems.
Preliminary analysis of existing tidal data and modeling suggests that an appropriate culvert design might overcome this constraint. With funding from MassBays Healthy Estuaries Grant, an existing hydrodynamic tide-height model (Woods Hole Group 2011) was expanded to assess various culvert configurations to allow salt-marsh recovery, project structures and permit a gradual restoration of tides and salinity.
Based on analyses of different scenarios, recommendations were made for the restoration of 23.5 acres of salt marsh.Details of the study conducted by Woods Hole Group are provided in the document below.