Indiana's 142-mile extension of Interstate 69 between Indianapolis and Evansville will siphon hundreds of millions of dollars away from other road and bridge projects in coming years, according to a report from an environmental group.

The report by the Hoosier Environmental Council concludes that the highway's nearly $3 billion estimated cost will consume one-fifth of funding available for state highway construction and maintenance projects between 2012 and 2014. In 2013 alone, nearly 30 percent of Indiana's highway funds will go toward I-69, the report said.

The result will be that many projects across the rest of the state will be stuck in "shovel ready" mode, or never leave the drawing board, said Tim Maloney, the council's senior policy director.

Maloney said in the report released Monday that dedicating a fifth of the state's highway funds to a single project over the next few years "will imperil the state's ability to fulfill its responsibility to provide safe and reliable transportation solutions to other areas of Indiana."

By the time Gov. Mitch Daniels leaves office in January 2013, Indiana will have spent nearly $1 billion to build about 90 miles to the highway between Evansville and the Crane Naval Surface Warfare Center in Martin County, the Evansville Courier & Press reported.

That means Daniels' successor will be left to figure out how to pay to finish the remaining sections and determine the pace at which that work will be completed.

A spokesman for Republican U.S. Rep. Mike Pence, who is running to succeed Daniels, said the congressman will unveil more detailed plans for how he would handle the remaining stretch of the I-69 extension closer to the 2012 elections.

For now, Pence said he considers the project a top priority and has supported it since late Gov. Frank O'Bannon announced the planned route in January 2003.

"I have always believed that roads mean jobs," he said. "... Finishing I-69 will create jobs in Indiana, and I believe this project should be completed."

Former Indiana House Speaker John Gregg of Sandborn, a Democrat who is considering running for governor, is still catching up on issues related to the highway but considers the highway project "extremely important," said spokesman Steve Campbell.

"Every time he's in Southern Indiana, he says this comes up. He's talked to people in Bloomington and Evansville, all up and down the route. He wants to get back up to speed," Campbell said.

Jim Wallace, a Fishers businessman who is also running for governor, called the I-69 extension "one of the top priorities, I think, for economic development for the state."

He said he is working on a set of infrastructure projects the state could complete for $500 million and will announce that in the fall.

Daniels has been able to build the first four sections of I-69 at such a rapid pace because of the state's 2006 leasing of the Indiana Toll Road in northern Indiana for 75 years that generated $3.85 billion to speed up projects across the state.

Of that money, $700 million was set aside for I-69. That will cover much of the roughly $1 billion to build it between Evansville and Crane

That money, though, will have run out by the time the next governor is looking to pay for what's left.

Because the state isn't far along in the planning process on those sections, no detailed and up-to-date cost estimate exists.

However, based on plans released in recent years, the cost of building the highway between Crane and Indianapolis would likely be between $800 million and $1.7 billion, with much of that coming in the suburban area closest to Indianapolis.

Will Wingfield, a spokesman for the Indiana Department of Transportation, said the state might have a draft environmental impact statement started, or even finished, by the time Daniels leaves office.