If you’re driving down a San Antonio street with no posted speed limit sign, the law sets the default speed limit at 30 mph.

But as residents continue asking city leaders to slow traffic through neighborhoods, officials question whether that number should drop to 25 mph and whether changing it would actually make drivers slow down. 

At a Transportation and Infrastructure Committee briefing on Tuesday, city staff outlined early findings from a pilot program tied to a Council Consideration Request from Councilwoman Marina Alderete Gavito (D7). The Jan. 29, 2025 request asked the city to explore lowering the default, or “prima facie,” speed limit on neighborhood streets from 30 mph to 25 mph as part of a broader push to improve safety. 

Under Texas law, 30 mph is considered a reasonable speed for vehicles on urban residential streets unless otherwise posted. Cities can lower that limit, but only under specific conditions — either through engineering studies or by passing an ordinance that meets state requirements, including signage and annual reporting on enforcement and crashes. 

City staff said the effort is rooted in a simple goal: reducing injuries and deaths on local roads. Higher speeds increase the likelihood of serious crashes, and San Antonio’s Vision Zero policy — adopted about a decade ago with the goal of eliminating traffic related deaths  — prioritizes lowering speeds as a key part of improving safety. 

According to data presented to council members, a pedestrian struck by a vehicle traveling At 30 mph — the current default on residential streets — has about a 45% chance of being killed. At, 20 mph the chance of death drops dramatically to about 5%. 

But early findings from a February city pilot suggest lowering the number on a sign may not be enough to meaningfully change how people drive.

Earlier this year, the Public Works Department reduced the speed limit to 25 mph and installed signs along a stretch of Kampmann Boulevard near Babcock Road and collected speed data before and after the change. The results showed only marginal differences.  

In one location, average speeds heading northbound dropped from about 31.6 mph to 31 mph. At another location, speeds going southbound increased from 30.1 mph to 31.2 mph.

The city’s pilot program on Kampmann Boulevard found the reduced speed limit signs had little measurable impact on how fast drivers traveled through the corridor. 

Credit: Diego Medel / San Antonio Report

Those findings mirror a similar city effort from 2015, when reduced speed limit signs were installed in nine neighborhoods and data was collected at more than 200 locations. About half of those areas saw slight decreases in speed, while the other half saw slight increases.

“We know, and we’ve shared some of this in the past, that signs, by themselves, have limited influence on the behavior of a driver,” Public Works Director Art Reinhardt told committee members this week.

That conclusion shaped the department’s recommendation: rather than relying solely on signage, the city should pursue a broader, multi-pronged strategy that includes engineering changes, enforcement and public outreach and education efforts. 

Committee Chair Councilman Jalen McKee-Rodriguez (D2) echoed that sentiment, adding that the results reflect what many residents already experience on neighborhood streets, noting that even physical traffic calming measures don’t always produce the intended results. 

“A large part of controlling driver behavior is going to be the way that we design roads,” he said. “But you look at areas where we do have medians and bulb outs and speed bumps, and people are driving over the speed bumps and flying. They are driving over medians, knocking over signs, running into fences.” 

McKee-Rodriguez pointed to driver behavior as a central challenge that could be addressed through outreach programs similar to the statewide initiatives like “Click It or Ticket” or the “Don’t Mess with Texas” campaigns. 

“We can change speed limit signs, we can add speed bumps. We can re-engineer and redesign roads,” Mckee-Rodriguez said. “But if you don’t change the way that you drive and the way that you treat other drivers on the road and the community that you live in, nothing is going to change.”  

Council members also raised questions about enforcement and whether it is happening where residents say they need it most.

McKee-Rodriguez said many constituent complaints about speeding come from neighborhood streets, where residents say they regularly see drivers exceeding posted speed limits but see little visible enforcement.

“Are police patrolling those areas? Are they stopping speeding in neighborhoods? Where are they spending the bulk of their time?” he asked. “I don’t know what data that would require, but I would be interested in … anything that might help us determine if we are being efficient and diligent in our placement of officers throughout the community.” 

Alderete Gavito echoed those concerns, noting that speeding is one of the most common issues raised at neighborhood meetings across the city. 

“This is what we hear about on a consistent and regular basis,” she said. “So I do feel we have to do something.” 

Beyond neighborhood streets, council members also pointed to challenges on larger, high-traffic corridors where traditional traffic calming measures like speed humps are not feasible.

Public Works officials said those types of roads would require a different approach, often involving larger, more expensive capital projects such as redesigned intersections, roadway narrowing or other infrastructure changes.

Over the next several weeks, staff will refine the scope of a potential citywide study, including defining what qualifies as a neighborhood street and estimating costs for signage, outreach and engineering analysis.

Those recommendations are expected to be folded into the upcoming budget process, where council members will decide whether to fund a broader effort.