Protecting Corn Neck Road

And the property that surrounds it
Fri, 09/29/2017 - 9:30am

Corn Neck Road is almost four miles of blacktop with water on both sides. It has two travel lanes that are 10 to 11 feet wide and shoulders of varying width. There are utility poles on the west side of the road, and water off the road drains directly into Harbor Pond, Trims Pond, Great Salt Pond, and the Atlantic. It was first paved in the 1930s and has been repeatedly been under assault by intemperate weather since Hurricane Carol in 1954, and has been repaired multiple times. The road was elevated in 1972 to protect it from storm surges, but despite that effort, the road suffered significant damage by Superstorm Sandy. The 1,800 feet that needed to be repaired by the Rhode Island Department of Transportation in 2013 cost $1.74 million, which was paid for by funds from the Federal Emergency Management Agency.

Corn Neck Road was repaired but not improved. (More recently, the lanes on Corn Neck Road were narrowed and re-striped to widen the shoulders on the east side of the road.)

Given that portions of Corn Neck Road are still vulnerable to sea level rise and storm surges, the Planning Board has initiated an ambitious study to see if those fault lines can be addressed. With funds from a Community Development Block Grant, the Planning Board commissioned a study report from VHB Consultants, an engineering firm out of New York City, last March. A draft of that study was presented to the Planning Board at its meeting on Wednesday, Sept. 13 by VHB representative Susan Moberg. There were a few members of the public at the presentation, primarily for other items on the Planning Board’s agenda, but Block Island Grocery owner Mary Jane Balser expressed her displeasure with the idea that the town should take responsibility for the cost and repairs of a road that is owned by the state.

“I’m very concerned that you’ll take this (plan) to the state, and they’ll say, ‘Great plan! Nice study! It’s all yours!” Balser said.

Town Planner Alison Ring said while the town was undertaking the study, it would not be responsible for paying for the upgrades, if and when they happen. “The town would not be doing this,” said Ring. “It would be the state.” Ring also said that while funding would not be local, “planning is local. The idea is for the town to have a plan” that would go beyond simply repairing the road back to the condition it was previously in if it is ever again damaged to any extent. “While the timing of various sea level rise scenarios is debatable, the impacts to transportation can be predicted now,” the study stated. “Based on input from the Town of New Shoreham and some residents of Block Island, it is clear that the island’s natural and man-made resources are at risk to damage from rising tides and storm surge. By adapting their ability to cope with the effects of climate change, the Town and residents can improve their climate change resiliency.”

The goals of upgrading Corn Neck Road were listed in the study:

- Maintain a transportation connection between the northern and southern parts of the island;

- Maintain access to public and private property along Corn Neck Road;

- Must be scalable to accommodate six feet above what is known as the Mean Higher High Water (MHHW) line.

The study recommends three possible approaches to protecting portions of Corn Neck Road from its beginning at Bridgegate Square up to Scotch Beach — about 1.16 miles of road.

These recommendations include elevating the road itself to building a series of bridges that would lift traffic off the road. The study included non-transportation alternatives, such as building revetments or installing rip-rap to quell the flow of water over the road.

According to the plan, elevating portions of 6,000 feet of vulnerable road between Bridgegate Square up to Scotch Beach so that it would be up to six feet above the MHHW line would cost about $9.8 million. 

The bridge alternative is more complicated and more costly — estimated at about $77.5 million. According to the plan, three bridge structures would be built between Bridgegate Square and the entrance to Scotch Beach at particularly vulnerable areas.

The third option is road relocation and elevation. At a cost of $11.5 milllion, it would also require reconstructing 1,100 square yards of driveways with gravel or common fill, creating 16,000 square yards of vegetated slope work to tie the new slopes back to existing grade; and acquiring some 3,700 square yards of property to accommodate the shifted roadway.

Planning Board member Socha Cohen asked Moberg how the plan, the structures of which, when built, would last 55 years, protected against storm surge. 

Storm surge, Cohen said, “can do the same damage without sea level rise.”

Moberg said that storm surges are happening now and they “already go over the road without sea level rise. If we planned for that, we’d be adding more height to everything.”

“Where does that put homes?” Cohen asked.

“Isn’t that the responsibility of the home owner?” asked Board member Sven Risom.

Cohen also asked if the study considered any off-shore storm surge or sea level rise mitigation.

Moberg said they had, but said “it would probably be difficult to permit. That would be a good thing to discuss with the CRMC” Coastal Resources Management Council.

Risom said that he was concerned about Bridgegate Square to a higher degree than the study took into consideration. “I’m worried that there will be a tremendous amount of rain with these storms,” said Risom. “I think Bridgegate Square is under much more stress than anyone else believes. I’m worried about the grocery store. It could be cut off for days.” Member John Spier said he was also worried about the impact sea level rise or a storm surge could have on Bridgegate Square.

Member Denny Heinz suggested that the planners should also consider moving the utility poles underground. “Overtime, it would be cheaper,” he said.

Moberg said the group was shooting for a final presentation to the Town Council in January 2018.