The first phase of the Manhattan Regional Airport runway reconstruction is officially underway.

The airport closed Tuesday night and will remain closed until 7 a.m. Friday. City Manager Ron Fehr briefed commissioners Tuesday on the temporary closure.

“This is where we’re shortening the main runway down to 5,800 feet so what they’re doing right now is re-marking everything. Once they get the threshold changed and marked, there is a scheduled flight for later that (Friday) morning,” he said.

The $31 million project was approved by the Manhattan City Commission last August. Fehr says the second phase of runway reconstruction will begin around May 12 and last through July 19.

“That’s a full closure as we have to do the primary grading at the intersection of the two runways and then anticipating July 19 the Crosswind Runway would reopen,” he said.

The airport will remain closed through Aug. 31, with a planned reopening the following day.

Federal grants from the FAA and Defense Community Infrastructure Program reduced the city’s share toward the project to about $3 million.

Fehr also informed commissioners of a change order to be presented on the April 4 meeting consent agenda.

“When the contractor tried to order the conduit that FAA requires for navigation aids on the project, they found out that conduit is no longer manufactured, even though it was specified in our documents. They worked with the FAA and found a substitute, but it is a $99,000 change order,” he said.

Fehr says it is grant eligible but that the change order did come as a surprise to city staff.