Eel Grass Restoration

Maine's eelgrass meadows form an important marine and estuarine coastal aquatic habitat. Along with other plants, eelgrass forms the base of food production in the sea. Eelgrass provides shelter for juvenile fish, and invertebrates, is a site for primary settlement of the larvae of some bivalve mollusks and invertebrates, and in certain locations helps to stabilize unconsolidated sediments and shorelines.

In 2021, the Town of Harpswell applied for a Maine Natural Resource Conservation Grant to study the effectiveness of helical moorings (also know as conservation moorings) in historically mapped eel grass habitats. In 2022, the grant was awarded to the town in the amount of $233,999 to study 20 helical moorings in three specific coves over the next five years. The installation, yearly dive inspection of the sites and mooring gear will all be covered under this grant until the year 2027. In the end, the study could show if helical moorings can promote healthy eel grass habitat in areas where traditional mooring gear scarred the ocean bottom. If true, more moorings can be issued within eel grass beds if the applicants agree to use a helical mooring.   

Traditional Mooring Tackle                         Helical Mooring

Traditional mooring tackle scars the ocean bottom by the dragging the chain when the vessel moves with the tide and wind. The swing radius of the bottom chain will trench a circle around the mooring anchor (block or mushroom), destroying any habitat in its path. Helical moorings are held in place by a "screw anchor" with a set of rode's depending on the vessel size. The rode's lead to the remaining mooring tackle and buoy, which keeps the tackle off of the ocean floor, preventing bottom scarring. 

Bottom Scarring Caused by Traditional Mooring Tackle