The St. Paul Downtown Airport’s flood wall will be partially deployed as the Mississippi River is due to hit its major flood stage by Monday, transportation officials said.

Holman Field, which is adjacent to the river, already is protected by an earthen levy.

The deployable part of the flood wall can reach an additional 3,200 feet in length — cutting one of the runways short — and reach a height of 8.5 feet.

As of Thursday, officials with the Metropolitan Airports Commission said they were not certain whether they would deploy the wall enough to cut their runway short — but will make that decision Friday after the forecast is updated.

The initial plan is to build the wall to 75 percent of its height.

Wall construction will continue through next week.

The airport will remain open during the construction. Services, including the restaurant, will not be affected, the MAC said.

Since the wall was built in 2008, it has been used five times.