What if, instead of basing policy around the presumption that people will drive more every year, transportation agencies started making decisions to reduce the volume of driving? And what if they succeed?
A new report from the Massachusetts Public Interest Research Group quantifies what would happen in that state if driving rates come in one percentage point lower than the state DOT’s current annual projections. For instance, in a year that the DOT forecasts 0.49 percent growth in driving, MassPIRG hypothesizes a 0.51 percent decrease. MassPIRG estimates that the statewide effect from now until 2030 would add up to about $20 billion in savings and 23 million metric tons of carbon emissions avoided.
The effects grow as the decline compounds over time. In the first year, a one percentage point change in driving rates would save about $167 million in avoided costs of gas, road repairs, and traffic collisions. By 2030, the savings would rise to $2.3 billion per year.
Broken down by category, the state would save about $1.9 billion on road repairs over the 15-year period. Drivers would net $3.8 billion in savings on car repairs and another $7.7 billion on gas purchases. And auto collisions would cost $6.7 billion less to society, as people avoid medical expenses, property damage, and lost wages.