5 minute read
Belcher Street Marsh
Kentville, Nova Scotia, Canada
Implementing Nova Scotia’s first hybrid foreshore marsh. Acadian settlers introduced agricultural diking in the upper Bay of Fundy of Nova Scotia and New Brunswick in the seventeenth century; since then, the region has lost 80% of its nutrient-rich tidal marsh. Now protected by about 241 kilometers of vulnerable dike infrastructure, the towns, farmlands, and wildlife habitat of the Bay of Fundy dikelands are susceptible to flooding and other climate change effects. The Belcher Street Marsh, part of the Making Room for Wetlands Project, is the site of a dike realignment and tidal wetland restoration to increase the resiliency of the macrotidal Jijuktu’kwejk (Cornwallis River), reduce neighboring towns’ flood risk, and restore almost 10 hectares of tidal wetland on former farmland. In June 2018, a tract of dike over one kilometer closely following the river was reduced, straightened, and realigned and a tidal channel excavated to open a section of fallow and underused agricultural land. A living shoreline on a section of riverbank particularly vulnerable to erosion is now in place and augmented with root wads, wattle fencing, vegetation mats, and live silt fences. Postrestoration revegetation of the site has grown from 30% bare ground in the first year to less than 6% by the third year.
Producing Efficiencies
The Belcher Street Marsh project reduced (by 500 meters), straightened, and upgraded the original over one-kilometer dike along the sinuous Jijuktu’kwejk (Cornwallis River), lessening the infrastructure that required labor-intensive, costly maintenance and upgrades and restoring tidal wetlands that protect surrounding areas from flood and erosion. Extensive baseline monitoring identified areas with issues like riverbank scouring and erosion. Future adaptive management techniques identified included a hybrid living shoreline to slow water flow, prevent scour, and increase sediment deposition at selected locations. The excavated tidal channel improved pond connectivity with the larger drainage network and promoted rapid revegetation and soil stability at the site.
Using Natural Processes
Restoring almost 10 hectares of tidal wetlands made Kentville more resilient to floods and protects the realigned dike and the land beyond from storm surge, waves, and erosion. A living shoreline planted with native salt marsh species stabilized the bank at certain at-risk areas and provides additional wildlife and plant habitat. Adaptive management techniques, including wattle fencing and brush mats at scour locations and small conifers to fill gaps in the root-wad revetment, helped slow scour and enabled the marsh platform behind to increase and revegetate rapidly so that only 6% of the ground remained bare three years after restoration.
Broadening Benefits
As a Making Room for Wetlands educational site, the Belcher Street Marsh is an excellent introduction to the concept of nature-based solutions. The relatively accessible site has been used for undergraduate and graduate student research projects on a variety of topics and as a hands-on field-trip destination for an experiential-learning secondary school. The site imparts lessons on community vulnerabilities to the hazards posed by climate change; local land use patterns and planning; and the barriers to the project, the drivers that pushed it forward, and the lessons learned along the way.
Promoting Collaboration
The project was a collaborative effort involving the Nova Scotia Department of Agriculture, CBWES Inc., and Saint Mary’s University, in addition to Dalhousie University, and Department of Fisheries and Oceans Canada. Making Room for Wetlands projects like this one follow a nonlinear framework for managed dike realignment and tidal wetland restoration that comprises these general stages: monitor, engage, gather baseline, design, and implement. This project provided valuable insights for future tidal wetland and managed dike realignment projects, fostered continued collaboration with the Province of Nova Scotia on future Making Room for Wetlands projects, and opened the door to new partnerships.
