In keeping with other U.S. cities, emission inventories show that power generation and transportation are the two main sources of carbon pollution, making up 80% of San Antonio’s greenhouse gas emissions.

Fortunately, CPS Energy has been a national leader in solar and wind energy, and aggressive in the pursuit of energy conservation. It was just named “Power Utility of the Year” by the Smart Electric Power Alliance due to its leading-edge efforts in renewable energy, energy storage, and distributed energy.

By comparison, local progress in reducing vehicular travel is “flat/getting worse” according to the SA2020 dashboard. Appropriately, the SA Tomorrow Sustainability Plan, adopted on Aug. 11, 2016, calls for a substantial 26% reduction in vehicle miles per person from 2013 to 2040. (One vehicle going one mile is a vehicle mile.)

Reducing vehicle miles travel has many positive impacts beyond just environmental ones. A mere 10% reduction in vehicle miles of travel would, for example, increase average household disposable income in San Antonio by nearly $600 per year and reduce annual auto accidents by more than 2,200. The State of California now requires transportation and land development plans to be evaluated based on the expected reductions in vehicle miles.

Credit: Graphic by Bill Barker

Lessons can be learned by studying the only three urbanized areas the size of San Antonio that have reduced their average vehicle miles per capita in the last 20 years: Portland, Ore., Sacramento, Calif., and San Jose, Calif. All three cities have opened light rail systems in the last two decades, have less than 0.9 mile of freeway per 10,000 population, and have increased population density to at least 3,500 persons per square mile.

By comparison, San Antonio has a relatively underfunded bus transit system, more than 1.5 miles of freeway per 10,000 population, and a density essentially the same as Portland’s in 1995. In the 20 years ending in 2015, the average vehicle miles per capita in the San Antonio urbanized area has increased by 6.7%.

Unless San Antonio wants to see vehicle miles continue to climb, it needs to develop a 21st century transit funding approach, redirect road investment to improve local street networks, and continue to integrate multimodal transportation with efficient land development.

Bill Barker is recognized as a fellow by both the Institute of Transportation Engineers and the American Institute of Certified Planners.