State transportation officials are warning of two major highway closures on Oahu later this week, meaning drivers will probably want to avoid those areas or seek alternate routes.

Starting Sunday night, there will be two consecutive weeks (excluding weekends) of full overnight closures on the westbound H-1 freeway in town, from Vineyard Boulevard to Halona Street.

Also, on Thursday, road crews will close Kalanianaole Highway in both directions between Hanauma Bay and the Halona Blowhole from 8:30 a.m. to 2:30 p.m. as they wrap up major repairs to the Ihi­ihi­lau­akea Stream Bridge.

The upcoming overnight freeway closures will run Sunday to Friday, beginning 8 p.m. each night and lasting until 5 a.m. the next morning.

Meanwhile, the eastbound H-1 will be down to one lane from 9 p.m. to 5 a.m. — so for the next two weeks, the entire freeway will be down to a single eastbound lane for much of the night and early morning hours, excluding weekends, according to the state Department of Transportation.

The work is part of the agency’s H-1 Freeway Rehabilitation Project, which started in September for overdue repairs to the freeway in town. The work allows crews to fully close the H-1 in one direction for up to 120 nights. Crews are on pace to complete the project around July, according to DOT spokes­woman Caro­line Sluy­ter, and thus far they’ve used only two of those full closures.

As the project nears completion, crews will likely close the freeway in one direction for about two months of night work, excluding weekends, Sluy­ter said.

The upcoming H-1 closures were scheduled to coincide with many local schools’ spring breaks to try to lessen the impacts, she added.

For more details on the project, visit h1rehab.com.

The Ihiihilauakea Stream Bridge in East Oahu, built in 1931, has seen some maintenance over the years but nothing major, said Ryan Sue­yo­shi, a project manager with DOT.

A $2.4 million project to replace degraded concrete and rebar on the bridge started in October. Now crews need a crane to lift the heavy equipment used for those repairs out of the gulch that runs below the Ihi­ihi­lau­akea, he said.

Sueyoshi recommended drivers who need to travel in that area during the full highway closure Thursday use Keala­hou Street, Hawaii Kai Drive and Luna­lilo Home Road as an alternate route.