DDOT officials said replacing the bridge was absolutely necessary. The stalactites beneath the structure are a sign of the deterioration. (Ricky Carioti/The Washington Post)

Some good news for thousands of car and bus commuters slowed by the District’s bridge rebuilding at 16th and Military Road NW: The District Department of Transportation says it can reopen all lanes on the rebuilt bridge on Wednesday, July 1, about two weeks early.

In the announcement, DDOT Director Leif Dormsjo noted one other benefit: “One of the main thoroughfares into the nation’s capital will now be fully open to traffic for the Fourth of July holiday weekend.”

I listed the bridge rebuilding among my top 10 transportation developments for 2015, and said “this is really going to hurt.” When fully open, the north-south bridge carries more than 30,000 vehicles a day. An additional 20,000 vehicles a day pass beneath it on east-west Military.

The project has left only one lane open in each direction on the bridge. “You can’t take away half the capacity and have nothing happen,” Paul Hoffman, the DDOT project manager, said in anticipation of the lane closings. The detour options are quite limited, because Rock Creek Park hems in 16th Street to the west. DDOT worked on diverting thousands of travelers to the nearest parallel route, which is Georgia Avenue.

But it hasn’t been as painful as I feared. What I feared was that the morning traffic would back up to Silver Spring, especially when the lane closings began, and drivers first realized what they had gotten themselves into. The morning traffic did back up about a mile on 16th Street when the lanes closed, but it could have been so much worse. Still, the delays and Metrobus detours have slowed progress for thousands of commuters.

Travelers do need to know that the speed-up for completion also speeds up the timetable for a full closing of 16th Street at the bridge to prepare for the reopening.

This is DDOT’s schedule for this weekend: The first closing is to begin at 10 p.m. Friday and end at 10 p.m. Saturday. The second closing is scheduled to start at 5 p.m. Sunday and end at 5 a.m. Monday.

Use these detours:

Northbound traffic should turn right onto eastbound Missouri Avenue NW, then take the ramp onto northbound 14th Street NW, turn left on westbound Aspen Street and turn right back onto northbound 16th Street.

Southbound traffic should turn left onto eastbound Fort Stevens Drive, turn right onto southbound 14th Street, go left onto westbound Colorado Avenue and turn left onto southbound 16th Street.

Even on a weekend, these full closings and detours are likely to create congestion on 16th Street, 14th Street, Military Road and other nearby streets.