Parallel grid ditches were dug in approximately 90% of mid-Atlantic and New England salt marshes in the 1920s through the 1940s. Today, managers must navigate the effects of past actions when making decisions about marsh hydrology and drainage that impact human health, ecosystem services, and marsh sustainability. Managers must also consider how stressors such as sea level rise impact marshes. A collaborative research project helped to address this challenge by working iteratively with end user groups to develop a decision support tool for marsh hydrology management strategies that promote sustainability and delivery of valuable ecosystem services under future sea level scenarios.
About this tool
The Marsh Sustainability and Hydrology Decision Support Tool allows users to select different combinations of tidal range, suspended sediment, ditch density, and sea level rise variables and visualize predicted outcomes over different time frames. The tool predicts potential outcomes of ditch and runnel maintenance in micro- and macro-tidal salt marshes under different scenarios of suspended sediment input and sea level rise. Outputs include elevation, vertical accretion rates, and habitat distribution along creekbank edges and in the marsh interior. The tool is based on a two-dimensional model (Marsh2D) and informed by field data collected on Cape Cod, Massachusetts. Model outputs are easily transferable to other systems that can be implemented by a broad group of end users.
You can also access the code to the Marsh2D model which is the basis for the tool.