PROVIDENCE, R.I. (WPRI) – The rusting green unused frame of the old Sakonnet River Bridge will likely remain an eyesore for several more years as state officials examine the risk that demolition poses to certain marine life.

Back in 2012, when the new Sakonnet River Bridge opened to motorists traveling between Tiverton and Portsmouth on Route 24, state transportation officials said the old bridge would likely be torn down in a year.

Now three years later, transportation officials say they’ve been asked by the federal government to do an additional environmental review to “ensure protection of endangered species including the Green Sea Turtle, the Leatherback Sea Turtle and the Kemp’s Ridley Sea Turtle, as well as the marine life including Loggerhead Sea Turtles and Atlantic Sturgeon,” according to R.I. Department of Transportation spokesperson Charles St. Martin.

“In October, RIDOT submitted these studies to the National Marine Fisheries Service and the National Oceanic and Atmospheric Administration, and we are currently awaiting their review and approval,” St. Martin said.

The state hopes to put the project out to bid in the fall, which would put the start of the 18-month demolition in the spring of 2017, he said.

But RIDOT’s acting chief engineer, David Fish, said the federal government’s review may slow that timeline down even further.

“Some of the comments that they’re requesting is we go out there and map where these species may habitat,” Fish said. “We have to do some background and some work to see what exactly, what type of effort is involved to do this mapping.”

Fish said officials were originally looking at detonating the bridge – as they did with the old Jamestown Bridge in 2006 – but based on the environmental concerns they will likely dismantle the bridge a piece at a time, essentially reversing how they built it in 1954.

“Basically what we would do is pick it with cranes and lower it to a barge rather than explosively detonate and have it drop it into the water,” Fish said. “That would have a lot less effect on any habitat that is potentially in the waterway.”

The state has estimated it will cost $16 million to dismantle the bridge. Fish said he does not anticipate that cost to rise if RIDOT has to alter its plans based on the environmental recommendations from the federal government.

He said the state is eager to tear down the old Sakonnet, in order to reveal the new.

“We just spent $165 million on a brand-new structure,” Fish said. “We want to make it visible so everyone can see what a great asset it is to the state of Rhode Island.” Tim White( twhite@wpri.com ) is the Target 12 investigative reporter for WPRI 12 and Fox Providence. Follow him on Twitter: @TimWhiteRI