Considerations for salt marsh restoration design in a hypertidal estuary.

Abstract

Salt marshes around the world have been seriously impacted by human activities and are in need of restoration more than ever in our changing climate. However, successful restoration requires a better understanding of these systems than available in our region at present. To this end ground surveys and digital terrain data were used to conduct a morphometric analysis of representative tidal channels in the Avon Estuary. Channel morphology was strongly related freshwater discharge and channel order while drainage density, channel length, and sinuosity were related to site history and maturity. Hydraulic geometry exponents were established and used in conjunction with low-altitude photography and survey data to assess channel development at the Cogmagun Salt Marsh Restoration. Although developing on an acceptable trajectory the excavation of a single breach and channel at this site has had a significant effect on site development, and should be taken into consideration in future projects.