Old Pond Marsh

Funding Round/Year: 
Project Sponsor: 
Maine Coast Heritage Trust
MNRCP Region: 
Downeast Maine
Total Cost of Project: 
MNRCP Award: 
Project Type: 
Salt marsh at the Old Pond Marsh project site, photo by Maine Natural Areas Program
Project Description: 
This Project is enhancing the functions and values of approximately 19 acres of salt marsh (see also the 2016 Old Pond-Dembska project, which helped fund the conservation of this site). The enhancements to the marsh surface will address past agricultural modifications in order to interrupt the “mega-pool trajectory.” MCHT is working with the US Fish and Wildlife Service Salt Marsh Adaptation & Resiliency Team (SMARTeam) and a private contractor to restore the natural single-channel hydrology in impacted areas of the marsh and restore salt marsh vegetation. This work will halt the subsidence of the salt marsh by fixing the hydrology and will also improve accretion to build platform elevation at a higher rate than sea level rise. The Project team will use a 4-Tiered approach: Tier 1 involves halting subsidence by correcting hydrology and identifying primary drainage channels within each small drainage unit (tideshed). Using ditch remediation techniques, the team will then reinforce tidal flow through selected channels which will allow the establishment of sufficient hydraulic head for primary channels to be self-maintaining. Tier 2 design focuses on increasing marsh elevation by promoting robust growth of Spartina alterniflora – this is achieved by regulating water levels within the rooting zone, by using pre-existing ditches or newly constructed runnels. Tier 3 design addresses wildlife needs-e.g., nesting habitat for salt marsh birds. Tier 4 design efforts document all enhancement work and provide a guide for long-term marsh management. By restoring the natural marsh hydrology and allowing marsh vegetation to re-establish, the marsh will be more resilient to sea-level rise as well as future restoration activities associated with the primary hydrological restrictions in the area. MCHT will oversee the restoration activities and will manage the Premises long-term for its natural resource values. The majority of work will be completed by early spring 2024.