The Ridge Road dike and tide gates have been in place for 85 years, and have become cemented as part of the town’s character. But what if that were to change?
It is difficult to imagine making changes to the tide gates and the West Branch of the Pleasant River, something that has remained largely consistent for generations. To help visualize some of the proposed restoration actions, Downeast Salmon Federation commissioned a set of illustrative renderings. The renderings were designed to imagine what a future restoration scenario might look like, with the individual panels showing potential stages in a phased, stepwise approach to tidal restoration in the system—from the current condition to a fully tidally transparent bridge.
Panel 1 – Existing Condition of the Ridge Road Tide Gates and lower West Branch Pleasant River at low tide
In their current condition, the Ridge Road tide gates are open as they drain water from the West Branch into the main stem of the Pleasant River during an outgoing tide. As the tide falls, river water becomes backed up behind the tide gates, which function somewhat like a dam.
Panel 2 – Potential future condition showing partial removal of the Ridge Road Tide Gates at low tide
With half the tide gates removed, river water would drain more quickly during a falling tide, resulting in more balanced water levels upstream and downstream of Ridge Road. Additionally, fish and sediment would also be able to move in and out of the West Branch. Better drainage would also increase the amount of exposed riverbank upstream of the dike.
Along with partial tide gate removal, this panel also shows some changes to the marsh directly above the dike. Lowering existing perimeter berms and digging drainage channels will help the marsh flood at high tides and reduce pooling on the marsh surface during low tides.
Panel 3 – Potential future condition showing full replacement of the Ridge Road Tide Gates with a single span bridge at low tide
With full tide gate replacement, water would move freely with the tides into and out of the West Branch. To prevent overtopping during storms, the new bridge and the rest of the dike would be raised above the projected sea level in the year 2100. Additionally, we’ve depicted some changes to the banks at the mouth of the West Branch to reduce erosion and improve nearby public green space.
Without tidal restriction, the vegetation growing above the bridge will match that which is found in the main stem of the river.
Panel 4 – Potential future condition showing full replacement of the Ridge Road Tide Gates with a single span bridge at high tide
With full tide gate replacement, water would move freely with the tides into and out of the West Branch. At high tides, water fills the drainage channels and expands outward onto the marsh surface. The marsh vegetation is vibrant and healthy.