SAN DIEGO — Major closures will be implemented along the Interstate 5 for two weekends in September to complete emergency repairs on the bridge deck over State Route 163, Caltrans said.

Crews will close the lanes to repair the bridge deck in both directions of I-5 near the Fifth Avenue on-ramp for about 56 hours each on separate weekends.

Messaging signs will be in place throughout the duration of each closure to help advise motorists of detours, as well as encourage alternate routes.

According to Caltrans, the first closure will begin at the southbound connector to Interstate 8 on Friday, Sep. 8 at 9 p.m. and will last through Monday, Sep. 11 at 5 a.m.

During this time, all traffic will be detoured to the eastbound I-8, while one lane of southbound I-5 will remain accessible from on-ramps south of I-8 for limited local and airport traffic. The Fifth Avenue on-ramp will be closed to motorists in order to limit traffic in the remaining open lane through the construction area, Caltrans said.

A map of the southbound detours can be found to the right.

Motorists are encouraged to take the southbound Interstate 805 before they are redirected eastbound on I-8 to avoid traffic delays through downtown.

The second closure along the northbound I-5 will begin at State Route 15 on Friday, Sep. 29 at 9 p.m. It will run through Monday, Oct. 1 at 5 a.m.

Two lanes of traffic will be detoured to SR-15, according to Caltrans. Remaining northbound I-5 traffic will be directed to eastbound State Route 94 via 19th Street and northbound SR-163.

Like with the first closure, one I-5 lane will remain available to motorists during the weekend, Caltrans said. The lane will be accessible by way of the eastbound State Route 75 connector and 19th Street, as well as the B Street/Pershing Drive on-ramps. The freeway on-ramp at F Street and westbound SR-94 connector will be closed to limit traffic using a single lane through the construction area.

Northbound motorists are advised to take SR-15 instead of I-5 to avoid delays through downtown.

“This proactive emergency work will ensure the structural integrity of the I-5 bridge through downtown for years to come,” Caltrans District Director Gustavo Dallarda said in a release. “During these two closure weekends, please avoid using I-5 through downtown and travel on alternate routes like SR-163, I-805 and SR-15.”

Residents in the area around the construction site are advised to be aware of construction noise and lighting, which are expected with the work.

The emergency repairs to the bridge deck began in mid-August with minimal traffic impacts on weekdays from 9 p.m. and 5 a.m. The project is anticipated to be complete by the end of October.

For real-time traffic information including traffic speed, lane and road closures due to construction and maintenance activities, motorists can visit Caltrans’ QuickMap. Drivers can also visit Caltrans on Twitter for up-to-date information.

Caltrans says the closure is subject to change due to weather, traffic incidents or other construction considerations.