Posted on October 25, 2024
(Oct. 24, 2024) In the mid 1840s floating dry docks known as camels were used to tow large whaleships through the shallows into and out of Nantucket Harbor.
It was cutting-edge technology at the time. Now, almost 200 years later, town sustainability manager Vince Murphy told the Select Board last week that if the harbor isn’t dredged soon, they might have to bring the camels back.
Murphy was joking, but the issue is a serious one. He has heard complaints from boaters, fishermen and scallopers that the island’s harbors are difficult to navigate.
The shallow spots make it easy to get a boat stuck. That is why the Natural Resources Department has been working on a 10-year harbor dredging plan that would see new channels created throughout not just Nantucket Harbor, but also Polpis and Madaket harbors.
The main channel into and out of Nantucket Harbor used by commercial ferries is not part of the problem. That route is maintained by the U.S. Army Corps of Engineers. This is for all other boats.
“We noticed a couple areas, the entrance to Polpis Harbor and Hither Creek in Madaket, that shone out like beacons in their own right, areas that really needed work. But the entire set of harbors, we wanted to provide a benefit to the public, to the boat community, everyone from recreational scallopers to people that just wanted to get to the mooring fields,” Murphy said.
The town has done dredging in the past, when very specific areas get into dire straits, but this proposal would change that.
“We’ve been doing reactionary dredging forever,” Murphy said. “This is changing the dynamic, this is the healthcare equivalent of preventative medicine.”
The plan is to create better routes, as the current ones often have to be moved and are continuously getting narrower and shallower.
Right now the Natural Resources Department is gathering data and feedback about what routes boaters travel in the harbor, the most popular destinations and currently the most challenging.
Murphy said the department has met with a number of committees and commissions and gotten feedback through a public forum held in September.
“We’re trying to use the harbormaster’s data for the last six years to try and show the channels that they’ve had over time and those have to move every year because sandbars move every year,” he said.
But it is not just about what boaters want. The environmental aspects of the project also need to be taken into account.
Most importantly, Murphy said, is to make sure the harbors’ fragile eelgrass ecosystems are not disturbed.
There is also the possibility of dredging in areas that could create better and more consistent tidal flow in the harbors.
“What we’re doing here is marrying up what the science says and what the community needs are, so it’s coming at it from both angles, so that it’s good for the community and good for the environment,” he said.
The next step in the project is to identify and prioritize the areas most in need, and determine where the channels should be located.
After that, the dredging plan will require permitting from the state before the first load of sand and silt is taken from a harbor. That could optimistically be as early as the second half of 2025.
Murphy said the cost of the project is still up in the air, and depends on how much dredging ultimately decide needs to be done.
Material dredged from the harbor could be used for beach nourishment projects across the island, Murphy said. With no shortage of erosion hot spots, the sand could be a hot commodity in dealing with sea-level rise.
“Reuse of the dredge material (sand) is a huge potential from this project. But we first have to come up with our dredge routes and understand how much material needs to be taken out,” Murphy said.
“Once we know that, we can understand what we can do with the material. If it’s not going to be a lot we can do beach nourishment but if we end up (dredging) a lot of material we can undertake a (more complex) coastal resilience project including beach nourishment on both the north and south shores.”
