The first runnel in Ipswich was completed on February 16, 2022. This phase of the work is done during the winter, when the surface of the marsh is frozen and easier to transport the equipment necessary to make the runnels, without harming the marsh. The small “island” of material shown here, removed to drain the surface water, will grow vegetation over the spring and summer. Runnels typically take a day or two to create.
Runnels are shallow channels that are excavated to restore small creeks that drain off any accumulated surface water from clogged ditches. When the marsh can’t drain, the grasses die. The water that used to flow through the restored ditches is diverted to the remaining ditches keeping them clear of clogs and forcing sediment to the marsh surface where, together with healthy plant growth, allows the marsh elevation to increase, as it would naturally in a healthy marsh. By restoring the natural flooding process nature does the heavy lifting and can keep pace with sea level rise without ongoing expensive and disruptive intervention.
Below, watch a clip of how the machine is carefully moved across the marsh, using wooden platforms.