Last week, about 100 contractors interested in building the $1.9 billion Southwest light-rail line nibbled cookies and exchanged business cards in the sunny fellowship hall of St. Andrew Lutheran Church in Eden Prairie.

They were there to learn more about how the Metropolitan Council has retooled the project’s construction bid package after four bids were thrown out in September because they were too expensive and “nonresponsive.”

“I’m here because this is an awesome project, with good, sustainable work,” said Della Young of Minneapolis-based Young Environmental Consulting Group.

Southwest’s planners have made a number of changes to the construction plan, changes they say will make it easier for contractors to build the 14.5-mile line from downtown Minneapolis to Eden Prairie. The new bids are due Jan. 9 and will be awarded in April.

But planners decline to say how much these changes will save or quantify the project’s construction budget.

They claim revealing those figures would defeat the purpose of a competitive bidding process. So far, about $221 million in local funds have been spent on the project, but heavy construction is not expected to begin until next spring.

“We want to keep that under our hat,” said Southwest project director Jim Alexander. “I’d like to think we’re saving some dollars; we have to see where the bids come in at. That will be the proof in the pudding.”

The original bids from four construction partnerships ranged from $797 million to $1.08 billion.

On Monday, only the two lowest bidders attended the contractor mixer — Ames Kraemer SWLRT Joint Venture ($797 million) and Lunda/C.S. McCrossan ($808 million). Both partnerships declined to comment on the new bid package.

The two highest bidders did not attend — Southwest Rail Constructors bid $1.07 billion, and Southwest Transit Constructors came in at $1.08 billion. It’s unclear whether they’ve dropped out.

Of the five companies that make up the high-bidding joint ventures, only Mortenson responded to a request for comment on whether new bids would be submitted. The Golden Valley-based firm said it is “evaluating its options.”

Four months have been added to the already delayed construction timeline, mostly to pare unspecified overtime costs, project officials said. This includes closing the Kenilworth Trail for an additional 111 days so work on a controversial tunnel can be done at a more reasonable pace, project officials said.

All told, the popular bike and pedestrian trail will be closed for 1,050 days. The tunnel has prompted neighbors to file a federal lawsuit against the council, claiming it violates national environmental laws. A decision in that case is expected soon.

Another change involves stepping up a plan to shift up to $216 million in local funds to the general contractor, reducing its upfront financial risk, Alexander said.

The council has also barred 36 subcontractors that worked on the preliminary design and engineering portion of the project from participating in construction of the line, claiming a possible conflict of interest. This affected three of four contractors that originally bid on the construction package, which is why the council dubbed the bids “nonresponsive.”

Tim Worke, CEO of Associated General Contractors of Minnesota, an industry group, said those firms “are very concerned, not only for the lost opportunity, but also for the future of other potential projects,” Worke said.