McAllen updates traffic-signal program; city testing AI detection and seeking funding for timing studies

Marlene Garza, a city staff member in traffic operations, told the McAllen City Commission on May 27 that the city has connected 162 intersections and has 217 total intersections citywide while continuing work on signal maintenance and modernization.

The presentation centered on the city's 2018 traffic-signal bond, which Garza said paid for new cabinets and controllers, expanded communications capability and supported a signal-timing study intended to make remote timing adjustments and speed troubleshooting. "We were able to purchase 98 of these, traffic signal cabinets and controllers with the bond," Garza said, adding that staff secured work at roughly 52 additional intersections to maximize the bond's investment.

The timing study covered 162 intersections, Garza said, and the city used an Ethernet port and other communications upgrades to bring roughly 60% of intersections online after leveraging a city Wi-Fi rollout. She described incremental improvements already underway, such as installing black backplates on signals and upgrading signs, and said the city is testing audible pedestrian signals at high-walk-volume locations and near schools to help people who are visually impaired.

Garza said staff are in a testing phase for new vehicle-detection systems, comparing loop detectors against radar and video systems that include AI capabilities. She provided a range for equipment cost: "You're looking at $16,000 an intersection up to $32,000 an intersection," she said. Garza described trade-offs: radar is cheaper, while video with AI can provide richer safety and forensic data.

Commissioner Joaquin "JJ" Zamora and others pressed staff on evaluation and metrics. "Do we have any data that shows that the $750,000 spent on a study ... actually resulted in improved traffic flow?" Zamora asked, requesting ways to measure return on investment. Garza said COVID changed travel patterns and made before-and-after comparisons difficult but that staff will look into available data and pursue consultant help to capture metrics going forward.

Commissioners discussed longer-term options including coordinated AI-based detection and video systems that can link multiple intersections for auto-adjusting timings. Garza said such systems work best when coordinated corridor-wide and that staff are prioritizing corridors that would yield the most benefit. She identified sources staff are pursuing to fund future projects, including the Highway Safety Improvement Program, a Category 10 congestion-management funding window through the regional MPO (named in the presentation as RGB MPO), the federal Safe Streets and Roads for All program, and the Transportation Alternatives Program.

The commission and staff also discussed operations and maintenance. Garza said the department does not yet have a full monthly operations-cost figure for new detection or AI services; she committed to providing a maintenance/ongoing-cost estimate to commissioners on request. Commissioners emphasized the need for measurable performance targets and queried how to gauge success for specific corridors and peak periods.

No formal motions or votes were taken during the presentation; the item was presented for information and discussion. Staff described next steps as securing grant funding, continuing pilot testing of detection systems, and developing a signal-maintenance and timing plan that would guide future CIP work.

Local context: the presentation noted the city's earlier bond work prioritized cabinets and controllers along 11 major corridors (identified in the presentation as five east'west corridors and five north'south corridors), and that the signal-timing component recommended updates on a three- to five-year cycle to preserve efficiency.