The estimated cost of building a light-rail Purple Line in the Maryland suburbs has risen by $220 million, making the project’s new price tag of $2.37 billion almost double initial projections, according to a federal report released Wednesday.

In 2001, when then-Maryland Gov. Parris N. Glendening (D) announced plans to link Montgomery and Prince George’s counties with light rail, the cost was projected at $1.2 billion.

Maryland transit officials have attributed previous cost increases to refining the rail line’s design — the route between Bethesda and New Carrollton grew early on from 14 miles to 16 miles — and taking inflation into account.

This latest increase was due primarily to financing costs and rising property acquisition expenses, the report by the Federal Transit Administration (FTA) stated.

The previous Purple Line cost estimate cited by the FTA, in November 2012, was $2.15 billion.

The estimated cost to build the Purple Line has almost doubled since 2001 as the proposed light rail route has become longer and more complex. (The Washington Post)

Henry Kay, head of project development for the Maryland Transit Administration (MTA), said the initial $1.2 billion estimate in 2001 probably was based on broad assumptions, such as the average cost per mile for rail construction nationally.

As the state has refined the Purple Line design, he said, engineers have found more “challenges” that add costs. For example, he said, trying to increase ridership by running on-street trains more quickly over intersections requires more expensive bridges.

“The [cost estimate] number at that time [in 2001] would have been based on lines on a map,” Kay said.

About 30 percent of the project has been designed, he said, enough to form more precise cost projections. Even so, he said, 20 percent of the new $2.37 billion estimate is a “contingency” for expenses that will not be known until more design has been done.

“We have a high level of confidence in this number,” Kay said.

Private companies — which the state is pursuing to design, build, operate, maintain and help finance the project as part of a public-private partnership — will complete the design, he said.

Kay said the latest increase is closer to $126 million.

(The Washington Post)

The state had given the FTA an updated estimate of $2.24 billion in the fall, subsequent to the $2.15 billion figure, he said. That interim increase reflected $94 million in higher property-acquisition expenses as local real estate values recovered from a slump, and additional costs to build more retaining walls along the route, officials said.

The $126 million was added more recently to reflect financing costs, which the state typically does not include in its budget estimates and which were not known until the MTA recently devised a more detailed financial plan, officials said.

Pat Burda, mayor of the Town of Chevy Chase, said she’s concerned the price will continue to rise as design continues. She said the project’s cost creep is one of the reasons the town has called for the state to more thoroughly study less expensive transit options, such as a rapid bus system.

“Think of the things we could do with that kind of money,” Burda said of the $2.37 billion.

The federal report released Wednesday that contained the higher Purple Line cost estimate did not express any concerns about it.

The report was part of President Obama’s fiscal 2015 budget proposal that included a Purple Line as one of seven large, new transit projects nationwide being recommended for federal construction aid.

The MTA has requested $900 million in federal construction grants for a Purple Line.

Obama’s budget, released Tuesday, seeks $100 million for Purple Line work in the fiscal year that begins Oct. 1. That money would not flow until a multi-year funding agreement is finalized, FTA officials said. That agreement is expected by spring 2015.

Federal construction money is not a certainty, however. Congress would have to approve the FTA’s full fiscal 2015 budget request of $2.5 billion for 26 transit construction projects nationwide.

If that amount is cut, projects that do not yet have federal funding agreements — such as a Purple Line — could be delayed, said FTA Deputy Administrator Therese McMillan.

“Let me stress that worthy projects don’t just drop off a cliff and disappear,” McMillan told reporters in a conference call Wednesday. “It’s just a matter of how soon we can get to them in the pipeline, based on funding appropriations from Congress.”

Maryland officials have said they hope to start construction on the line in 2015 and begin service by late 2020.

A Purple Line would be designed to provide faster, more reliable transit between suburbs than buses and directly connect Metrorail stations with Amtrak and MARC commuter rail stations.

A proposal to build a 14-mile light-rail Red Line in Baltimore also has grown more expensive, with its estimated construction costs up by $70 million to a total of $2.64 billion, according to the federal report. Those increases were due primarily to higher construction costs for underground stations and a maintenance facility.

A Red Line also has been recommended for $100 million in federal construction funding in the next fiscal year. Maryland officials are seeking $900 million in total federal aid for that line’s construction as well.