Major I-35 Southbound Closure Begins Today; Heavy Weekend Delays on Loop 1604

Major I-35 Southbound Closure in Downtown San Antonio

Commuters heading through the downtown corridor should prepare for significant changes starting today, Saturday, February 21, 2026. The Texas Department of Transportation (TxDOT) has officially closed the lower-level main lanes of southbound I-35 between I-37 and I-10. This weeks-long closure is necessary for critical bridge joint repairs as part of a $25.9 million downtown improvement project. While the upper-level lanes of I-35 will remain open, heavy congestion is expected throughout the day. Drivers are strongly encouraged to utilize I-37 or I-10 as alternate routes to bypass the downtown core until the project concludes in mid-March.

Loop 1604 and I-10 Interchange Disruptions

Major construction continues on the North Side as part of the Loop 1604 North Expansion Project. Several high-impact closures are scheduled for this Saturday, February 21:

• Loop 1604 Westbound: The main lanes are closed between the Stone Oak Parkway exit ramp and the subsequent entrance ramp until 5 p.m. today. Additionally, the westbound lanes from the I-10 interchange to the Babcock Road entrance ramp will remain closed through 5 a.m. Monday.
• I-10 Interchange Flyovers: Multiple flyover ramps at the Loop 1604 and I-10 interchange are currently closed. This includes the ramps connecting I-10 eastbound to Loop 1604 westbound, and I-10 westbound to Loop 1604 westbound. These closures will persist until early Monday morning.
• Frontage Roads: Expect delays on the eastbound Loop 1604 frontage road at the I-10 interchange and the left lane of the westbound I-10 frontage road, which are both restricted through the weekend.

Public Transport and VIA Service Alerts

VIA Metropolitan Transit has issued several service alerts due to the ongoing construction projects. Riders on Route 93 (Roadrunner Express) should note detours near the Loop 1604 and La Cantera area. Additional detours are in effect for Route 5 McCullough, Route 7 (US 281 Express), and Route 34 (South St. Mary’s). Passengers are advised to check the VIA goLine or their mobile app for real-time adjustments to stop locations and schedules.

Commuter Tips and Weather Impact

A cold front is moving through the region this morning, bringing gusty conditions. A Red Flag Warning has been issued for South Texas due to dry and windy weather, which may affect high-profile vehicles on elevated flyovers. With sunny skies and a high near 74 degrees, outdoor visibility will be excellent, but the complexity of the current roadworks means travel times will be longer than usual. Plan for an additional 20 to 30 minutes of travel time if your route involves the North Side or the I-35 downtown exchange.