, Newburyport, MA

October 11, 2012

Sand dumping off PI needs closer look

Newburyport Daily News

---- — It’s said you shouldn’t look a gift horse in the mouth, and that’s no doubt true when you are desperate for any horse you can get.

But we’d have to agree with the mouth-lookers who are urging caution over the Army Corps of Engineers’ offer to dump up to 700,000 cubic yards of sand off Plum Island — sand that is being dredged from the Piscataqua River in Portsmouth, N.H. The question is whether this sand is appropriate for Plum Island, and what such an infusion of non-native sand will do to local beaches.

Plum Island’s battle with beach erosion has been well documented over the past few years. Efforts to slow erosion — by dumping over 120,000 cubic yards on the beach and taking various emergency measures — have helped, but they have not solved the problem. A longer term solution is in the works, with the upcoming repair of the south jetty. It’s hoped that the jetty will change the flow of water and sand along the beach, to the benefit of the island.

The infusion of sand from the Piscataqua River, which would not occur for at least two years, seems on the surface to be a beneficial idea, and perhaps it truly is. The cost is relatively cheap, and the sand contains both fine and course grade.

There are some local residents and officials who have expressed concern over the plan, which was discussed yesterday at the meeting of the Merrimack River Beach Alliance. Among them is Newburyport’s conservation administrator Julia Godfredtsen and Plum Island activist Ron Barrett. They have some legitimate points that are worth exploring.

All sand is not created equally, and Plum island provides good examples of this. The sand grains at the northern end, near the mouth of the Merrimack, are far larger and have a more granular feel than the silt-like sand at the southern end. The importance of getting the right sand in the right spot was clearly shown in 2010, when the city of Newburyport paid some $50,000 to dump sand onto an exposed section of beach. The fine-grained sand was almost all gone within a few weeks. It was too fine for that area of the beach.

There is another concern to be considered, and that is the ecological impact of the sheer quantity of sand proposed to be brought here. There’s up to 700,000 cubic yards being considered, which is more than four times as much as was dredged from the mouth of the Merrimack River and dumped onto Salisbury and Plum Island beaches in late 2010.

Certainly this enormous quantity of sand will have a notable impact on Plum Island beach. The question is whether it is a good impact, bad impact or mixed bag. Does anyone know for sure?