Multiple lane closures on major roadways, including the H-3, H-1, Nimitz Highway and Ala Moana Boulevard, are scheduled for Saturday morning for the annual Race to the Base Triathlon, state officials said.

Westbound lanes will begin to close on Ala Moana starting at Kamakee Street at 3:30 a.m. and move westward. All lane closures are expected to be in place between 5:30 and 6 a.m., depending on the location.

Crews will begin reopening roadways as the last participant passes through the area, and all lanes are expected to reopen by 11:30 a.m.

The following lane closures are scheduled as follows:

>> Ala Moana Boulevard/Nimitz Highway: Two westbound left lanes will be closed between Kamakee Street and Valkenburgh Street.

>> H-1 freeway: Two westbound right lanes will be closed between the Valkenburgh Street onramp and the Kaneohe/Honolulu offramp (Exit 13B).

>> H-3 freeway: All lanes will be closed in the Kaneohe-bound direction between the Halawa Interchange and the Kaneohe Bay Drive offramp (Exit 15). Special duty police officers will assist traffic in accessing the Marine Corps Base via the Kaneohe Bay Drive onramp to the H-3. Motorists may also access the Marine Corps Base via Mokapu Road.

Electronic message boards will inform motorists of the closures. Motorists are advised to allow for extra travel time, use alternate routes, and drive with caution through the race areas.

Weekend lane closures are also posted on the Hawaii Department of Transportation’s website.