A swooping swath of Interstate 95 south in East Lyme and Old Lyme will be consolidated to simplify the outdated and unsafe stretch between the Rocky Neck Connector and Four Mile River Road.

State Department of Transportation spokesman Josh Morgan on Friday said a conceptual plan for the roughly $29 million project is subject to change before the tentative start of construction in 2028. There will be opportunities for input from the public as designs are finalized.

The Rock Neck Connector is the current home of exit 72, while exit 71 is on Four Mile River Road. The improvements are expected to take two years.

The preliminary rendering eliminates the looping portion of the Rocky Neck Connector, allowing drivers entering there at a new traffic signal to get up to speed on a longer, straighter expanse without having to fight the vehicles attempting to get off exit 71. The proposed 71/72 exit will begin north of the current Rocky Neck exit with opportunities for vehicles to get off in East Lyme at the traffic signal or in Old Lyme on Four Mile River Road.

Morgan said the area, which tallied about 100 crashes in a three-year span ending in 2019, highlights the failures of the state’s highway infrastructure “in terms of how it was built, how it was designed and how people are using it today.”

The fact that 85% of those crashes occurred in dry conditions points to deficiencies in the design and dangerous driving habits, according to the spokesman.

The tentative 2028 start date comes on the heels of the four-year, $148 million exit 74 reconstruction project expected to be completed in 2027.

The project received the endorsement of the Lower Connecticut River Council of Governments, which covers Old Lyme, on Wednesday. It will be taken up by the Southeastern Connecticut Council of Governments covering East Lyme next week.

Eighty percent of the project will be covered by federal funds and 20% by the state DOT, Morgan said.

The project is one of the first to emerge from a large planning study launched a year ago to identify ways to improve the interstate from Branford to the Rhode Island state line. Morgan said the I-95 Eastern CT Planning & Environmental Linkages Study, or PEL report, will identify early-, mid- and long-term projects to be implemented over the coming decades.

The relatively small-scale project makes it a good candidate for an “early action project” to kick off the improvements, according to Morgan.

Southeastern Connecticut Council of Governments transportation program manager Katherine Rattan on Friday said the final PEL report is expected this summer.

Rattan emphasized the need for safety in an area where the on-ramp from the Rocky Neck Connector and the off-ramp onto Four Mile River Road result in a lot of weaving from drivers getting on and off the highway.

“We have seasonal congestion, we also have weekend congestion that we exhibit especially around holiday time,” she said. “This will reduce the friction on the highway, which hopefully will result in fewer crashes.”

Further in the future are improvements to the exit 75 area in East Lyme, where the highway converges dangerously with Interstate 395. Morgan acknowledged the need for changes but said “there’s nothing concrete happening at the moment.”

He said any large-scale project there would require federal evaluation over and above the PEL study. But he said the DOT is hopeful some smaller early action projects stemming from the regional study can be implemented to improve traffic flow. He cited the exit 75 north off-ramp as an area that might be targeted for improvements in the near term.

Rattan said exit 75 remains a priority for the regional planning group and the state, due to its design and history of rollovers.

In 2007, a northbound tanker truck carrying about 7,000 gallons of heating fuel careened out of control and jumped across the highway near the intersection of Interstates 95 and 395, ramming into a southbound tractor-trailer and causing a pileup. Three people died and several were injured.

Rattan said she anticipates the PEL study will produce some “conceptual alternatives” for exit 75 in early- to mid-2024.

e.regan@theday.com