A nearby Austin street offers a useful test
One lane each way. Nearly the same trip time.
In August 2023, Austin changed a stretch of Barton Springs Road from four lanes to two. The City also added protected bike lanes and safer crossings. For one year, it measured speeding, travel time, crashes, and how people felt using the street.
Changing Barton Springs from four lanes to two did not cause large delays. South First still needs its own study.
Read the City’s final report ↗
When trips took longer
+5–9sec
in three of six weekday time periods
Test first.
Decide later.
Four questions
Did traffic slow down? Did the street get safer?
fewer drivers over 40 mph each day
Short traffic counts found 64% fewer drivers over 40 mph. A longer set of readings found 70% fewer.
reported crashes during the one-year trial
The average for the five years before the change was 12 crashes a year. No crash during the trial caused a serious injury.
to drive through the changed section
Two of six weekday periods became faster, one was unchanged, and three became 5–9 seconds slower.
said they felt comfortable on the street
Only 36% said that before the change. More than 70% supported or somewhat supported the project.
What happened to drive time?
Longer lines of cars did not mean much longer trips.
The line of cars sometimes looked longer because one lane replaced two. Even so, most drivers got through the traffic lights after the same number of green lights as before.
Average weekday travel time before the trial compared with its first year · Aug. 21, 2022–Aug. 20, 2024
FasterSlower
Eastbound · morning+5 sec
Eastbound · midday−3 sec
Eastbound · evening−4 sec
Westbound · morning+9 sec
Westbound · midday0 sec
Westbound · evening+5 sec
How many cars used the road each day?
Three one-day counts do not prove traffic stayed lower.
They were taken in different months and on different days, so the City says they should not be treated as a trend.
What the numbers do show
The July count was close to the count before the lane change. Average trips did not become much longer on Barton Springs or nearby east-west roads. These three counts alone cannot tell us why traffic changed.
Barton Springs compared with South First
The result is useful. South First still needs its own test.
QuestionBarton SpringsSouth First today
Lanes for drivers going straightFour became two
Mostly four between Barton Springs Road and Ben White Boulevard
Vehicles per day22,600 before; 17,000 to 21,300 after
The City has not published a current count for the whole stretch
How long the trip tookThe City published travel times from before and after the change
No comparable public study for South First
What is along the streetA park, a bridge, and large events
Homes, shops, restaurants, many driveways, and the Route 10 bus
Main traffic problemSpeeding and lines at traffic lights
Speeding, left turns, buses, crossings, and many entrances
What should happen nextImprove the tested design before making it permanent
Measure each part of the street before choosing a design or trial area
What South First is missing
We need a current count of cars and travel times on South First.
The City counted the 1000 block of South First in September 2022 and has traffic sensors at several intersections. Its public data does not include a current count for the whole stretch or a before-and-after travel-time study like the one for Barton Springs. Those measurements should come before a design.
See the City’s traffic count list ↗What South First can learn
Repeat the careful testing. Design South First for its own needs.
- Measure first.
Count cars, map left turns, measure speeds and trip times, and review crashes, bus delays, crossings, and nearby streets.
- Start with a trial.
Use paint and signs that can be adjusted. Set dates to review the results.
- Measure the full trip.
A longer line at one light does not always mean a longer drive.
- Share every result.
People should see the problems along with the improvements.
- Which lane layout fits?
Different blocks may need a center turn lane, planted islands, or extra space for bus stops.
- Can two lanes handle busy times?
Current car counts and left-turn patterns have not been compared.
- Would traffic move to nearby streets?
Those streets need to be measured before and during any trial.
- How do we judge safety?
A one-year trial gives useful information. Serious crashes are rare, so safety results need more time.
What this means for South First
Barton Springs makes a South First study worth doing.
The lane change did not cause large travel delays, and it reduced speeding. Before choosing a plan for South First, the City should publish current car counts, turning patterns, travel times, bus delays, crash data, and traffic on nearby streets. The group can then define a small trial and say in advance what success looks like.
See what happens next →City sources
Check the numbers.
Every Barton Springs result on this page comes from the City’s final report.
01City’s final 12-month reportCity of Austin · October 2024
02How the project changedCity of Austin project page
03Questions asked before the trialCity of Austin · June 2023
04Austin traffic-count mapCity of Austin · count locations and dates
05Locations of City traffic sensorsCity of Austin · device locations and status
06Planned South First transit workCity of Austin · planning recommendations
Checked July 19, 2026 · Missing South First data is identified above