The Main Street Bridge Over I-35E Won't Be Done Until Late 2026 — At Best

If your southbound commute runs through Lewisville, you already know the drill: merge, slow down, creep past the orange barrels, check the clock, sigh. Here's what nobody's been saying clearly — that squeeze isn't ending this summer. The Main Street bridge over I-35E won't be finished until late 2026 at the earliest, and January 2027 is also on the table.

TxDOT's contractor is completely rebuilding the FM 1171/Main Street bridge as part of a $105 million project that also widens 1.3 miles of I-35E main lanes and builds a new northbound frontage road from Fox Avenue to College Street. Not a patch job. This is a full structural rebuild — retaining walls, new drilled shafts for pillars, a poured bridge deck. The deck pour alone closed all lanes of FM 1171 for a stretch back in March. You don't rush concrete.

Lewisville's own project page puts the estimated completion of the Main Street interchange at late 2026. The Denton Record-Chronicle, citing a project representative, reported the bridge reconstruction could slip to January 2027. Six months of wiggle room on a structural project like this isn't unusual. It's also not comforting.

For Flower Mound residents heading south — toward DFW Airport, Las Colinas, Irving, or downtown Dallas — FM 1171 into Lewisville and onto I-35E is the corridor. There isn't a clean alternate that doesn't add time. The Denton I-35E/I-35W merge project, which affects the northern end of the same highway, isn't done until 2029. So the entire spine of the commute is under construction simultaneously, from Denton all the way down through Lewisville.

There is some good news: the bridge deck pour in March was a real milestone. Structural work has been progressing. This isn't a stalled project — it's just a slow one, because bridges are slow. The new northbound frontage road from Fox Avenue to College Street, once complete, should give commuters more options at that interchange than they've ever had.

That's future tense, though. Right now, treat late 2026 as the optimistic scenario and plan accordingly. Budget the extra commute minutes. Keep an eye on TxDOT's road condition tracker for periodic closure notices — weekend full closures have been a pattern throughout the project and will likely continue as crews finish the superstructure work. And if your employer has any flexibility on arrival times, now is the moment to use it.