The Texas Department of Transportation (TxDOT) announced that construction will soon start on San Antonio’s second diverging diamond interchange, a $40 million project slated for the Southeast Side of the city. The new interchange will replace the traditional at‑grade crossing at Interstate 37 near Southeast Military Drive, a corridor that has long suffered from heavy traffic and safety concerns.
Why a diverging diamond?
A diverging diamond interchange (DDI) temporarily shifts traffic to the opposite side of the roadway as vehicles pass through the intersection. This design allows left‑turning drivers to proceed without waiting for oncoming traffic, eliminating the need for a dedicated left‑turn signal phase. Traffic engineers say the configuration reduces the number of conflict points where crashes can occur and moves higher volumes of vehicles more efficiently.
Projected benefits
State traffic models project a 90 percent reduction in travel times for drivers exiting southbound I‑37 onto Southeast Military Drive. By streamlining the flow of traffic, the DDI is expected to ease congestion during peak commuting hours and improve overall corridor safety. Local officials highlighted that the project aligns with the city’s broader transportation plan to modernize key arteries and support economic growth on the Southeast Side.
Construction timeline and impacts
Construction is scheduled to begin later this year, with a target completion date of 2029. To minimize disruption to commuters, TxDOT plans to conduct most lane closures overnight, typically between 9 p.m. and 5 a.m. on weekdays. While the agency noted that some daytime and weekend work may be necessary to keep the project on schedule, they emphasized that these periods will be limited and coordinated with local traffic‑management teams.
Community response
Neighborhood leaders and business owners have expressed cautious optimism. Many recognize that the temporary inconvenience of lane closures will be outweighed by the long‑term benefits of reduced travel times and a safer driving environment. The city’s transportation department will hold public information sessions throughout the construction phase to keep residents informed and address any concerns.
Looking ahead
San Antonio’s first diverging diamond interchange, completed in 2022, has already demonstrated measurable improvements in traffic flow and safety. The success of that project helped pave the way for this new DDI, reinforcing the city’s commitment to innovative infrastructure solutions that serve families, support local businesses, and uphold the values of responsible stewardship.
When the project reaches completion, officials anticipate that the Southeast Side will experience smoother commutes, fewer accidents, and a stronger foundation for future development. The investment reflects a broader state‑wide push to modernize Texas highways and ensure that growing communities have the transportation capacity they need.
Original reporting: San Antonio, TX News (HLL/CB) — read the source article.
