Traffic and Road Safety in Houston

Growing populations and increasing numbers of cars on the road increase the impact of roadway congestion and issues with safety for all users

Traffic and its negative impacts are most severe in Houston’s urban centers than in Fort Bend and Montgomery counties.

Why traffic matters to Houston

Residents cite traffic as the biggest problem facing residents in the Houston area today.1 Street safety for all users is also a growing concern.2 Population growth, urban sprawl and an increase in car ownership rates are resulting in an increase in the number of cars on the roads which is outpacing investment in a transportation system that can accommodate such growth via multiple modes. As shorter commutes contribute to a higher quality of life and make a region more attractive, it becomes increasingly important to identify means of accommodating the increase in traffic flow and mitigate the unsafe impacts of traffic.3

The better we understand traffic and how it affects our region, the more we can do to implement effective, lasting solutions that improve life throughout Houston-area communities.

The data

Growing congestion drives increasing costs, delays and stress for Houston area residents

Congestion occurs when the demand for roadway travel exceeds the transportation capacity. Road congestion can be costly for residents and our communities, contributing to delays, missed meetings, lost productivity and increased fuel costs. Houston’s reliance on private automobile commuting makes congestion worse. Congestion cannot be addressed by widening or building new roads, it requires building a transportation system that creates more mobility options for people in every part of our region.

Since 1992, congestion costs for major Texas metropolitan areas have generally increased. However, Houston has had the highest annual congestion cost per automobile. In 2014, for example, Houston’s annual congestion cost per automobile was $1,490, compared to $1,185 in Dallas, $1,159 in Austin, and $1,002 in San Antonio.

Compared to similar “very large urban areas” around the nation, congestion costs Houston drivers $57 more per automobile per year. However, within certain Houston neighborhoods like Conroe-The Woodlands area, annual congestion costs are less than half the national average for small urban areas.

$1,490/yr.

The annual per-vehicle cost of congestion is higher in Houston than any other major cities in Texas.

Houston’s most congested roadways

The map below displays the most congested roadways in the Houston-The Woodlands-Sugar Land metropolitan area. In 2018, across the state of Texas, Houston had 12 roadways in the top 20 most congested roadways across the state, adding two to the list since 2015.

The Most Congested Roadways in Houston-The Woodlands-Sugar Land Metropolitan Area


Source: Texas A&M Transportation Institute.

The 3.6 mile stretch along the 610 loop between I-10 and US 59 is the most congested roadway in the metro area. It is also the most congested in the entire state. The estimated annual congestion cost for that segment rests at $119.4 million with an annual estimated 1.67 million hours of delay per mile. Houston is home to 12 out of Texas’s top 20 most congested roadway segments.

$119.4 million/yr.

Congestion on the stretch of 610 between I-10 and US 59 adds up to significant costs for area drivers.

Traffic delays due to congestion

Congestions also cause traffic delays, or time lost. Since 1994, the annual hours of delay for major Texas metropolitan areas have generally increased, with a slight dip during the latest recessionary period. 

In Houston, annual hours of delay per automobile commuter increased from 40 hours to 61 in 2014. Dallas and Houston have competed for the most hours of delay since 1982, but starting around 2005, Houston became the leader in the most annual hours of delay per auto commuter across major Texas metro areas. 

Despite having more than half of the state’s most congested roadways, the annual hours of delay per auto commuter in Houston are slightly lower than the average hours in large urban areas. Consistent with trends in congestion expenses, Montgomery County-area urban centers see less than half the traffic delay of an average small urban area nationwide.

Commuter stress

One of the most important consequences of growing traffic congestion is increased commuter stress. The commuter stress index is the ratio of the travel time during a peak period to the time required to make the same trip at free-flow speeds. A higher commuter stress index indicates a larger difference between the time it takes to travel free-flow and the time it takes to travel during a peak period.

A higher commuter stress index indicates more time is spent waiting, which is harmful to commuter’s physical and mental health. More time spent waiting in traffic also has implications for environmental concerns due to the extra release of greenhouse gas emissions.

In Houston, the commuter stress index was 1.39 in 2014, while it was 1.33 in Dallas and San Antonio, and 1.44 in Austin. In fact, Houston had a higher commuter stress index among the four major Texas cities until around 1993 when Austin overpassed Houston to have the highest commuter stress index.

Small cities also have congestion problems, but they count on good mobility as a quality of life aspect that allows them to compete with larger, more economically diverse regions. Conroe-The Woodlands area is a good example of this.

Rising crash rates highlight growing stress on Houston-area roadways

According to data from the Texas Department of Transportation, the three-county area has more crashes per 100,000 people than the state of Texas. In 2018, the three-county area experienced 2,437 motor-vehicle crashes for every 100,000 people, compared to the state average of 2,184 per 100,000 people.

The average crash rate in Texas increased by 17% between 2010 and 2018, while the rate across the three-county area grew by 28%. While the number of alcohol-involved crashes shrank at both state and regional levels, the decrease in the three-county area was slower than that of the state. While Texas saw a decrease in distracted driving crashes, the three-county area saw an increase, although rates remain lower than the state average as of 2018.

Within the three-county area, Harris County had the highest rate of motor-vehicle crashes per 100,000 population, followed by Montgomery County and Fort Bend County. Since 2010, Harris County also had the highest increase in the motor-vehicle crash rate, followed by Fort Bend County then Montgomery County. Also, Harris County is the only county in the region to see an increase in crashes caused by distracted drivers.

“In 2018, Harris County’s rate of car crashes per 100,000 people was 23% higher than that of the state.”

Traffic fatalities

Overall, the state of Texas had a higher traffic fatality rate per 100,000 population than the three-county area. In 2018, the traffic fatality rate was 11.70 per 100,000 people in Texas, compared to 7.42 in the three-county area. The traffic fatality rate fell by 1.07 in the three-county area between 2010 and 2018 but increased by 0.5 points in the state.

Regardless of causes, traffic fatalities are lower in the three-county area than state averages. Further, traffic fatalities have decreased more than the state averages in all categories, most significantly in the rates of alcohol-related traffic fatalities.

Within the three-county area, the traffic fatality rates per 100,000 residents in Harris and Montgomery counties are more than double the rates in Fort Bend County. However, traffic fatalities have decreased in all three counties between 2010 and 2018, with Montgomery County seeing the greatest overall decrease.

Startling pedestrian and cyclist crash rates highlight infrastructure deficiencies in the three-county area

The pedestrian and pedal cyclist crash rates are higher in the three-county area, compared to the state average. In Texas, there are 28 crashes involving pedestrians and 10 crashes involving bicyclists for every 100,000 people, but in the three-county area, there are 33 crashes involving pedestrians and 11 involving bicyclists per 100,000.

“The growth in pedestrian crash rate in the three-county area nearly doubles the average growth state-wide.”

Within the three-county area, the crash rates for pedestrians and people on bikes per 100,000 people are highest in Harris County and growing at an alarming rate. While Fort Bend County boasts the lowest pedestrian crash rates, pedal cyclist crash rates are lowest in Montgomery County, which is also the only county where rates for both crash categories are in decline.

Pedestrian and pedal cyclist fatalities

Consistent with trends for motor vehicles, fatality rates for pedestrians are lower in the three-county area than the state average despite higher crash rates. However, fatality rates for people on bikes are slightly higher. 

Within the three-county area, the pedestrian crash fatality rate is only higher than the state average in Harris County. Meanwhile, cyclist crash fatality rates are higher than the state average in both Harris and Montgomery counties, with Montgomery County’s rate being the highest in the region. Additionally, Harris County is the only county in the region where pedestrian crash fatality rates rose between 2010–18.

Resources

References:

  1. Klineberg, Stephen L. “The 2019 Kinder Houston Area Survey: Tracking Responses to the Economic and Demographic Transformations through 38 Years of Houston Surveys.” Rice Kinder Institute for Urban Research (2019).
  2. Vision Zero,” City of Houston.
  3. Schrank, David, Bill Eisele, and Tim Lomax. “2019 Urban Mobility Report.” The Texas A&M Transportation Institute with cooperation from INRIX (2019).