We’ve already discussed what the $10 billion in economic stimulus might mean for high-speed rail. But the Economic Recovery and Reinvestment Act signed into law by President Obama, also includes an increase in the tax benefit for many users of mass transit who can now save up to $1,000 a year or more on their transit commute. This represents a potential $440 a year increase in what they can save currently.

The Tax-Free Commuter Benefits, which let employees pay for mass transit tickets with pretax dollar, will increase the amount of pretax income that workers enrolled in employer-sponsored commuter benefits programs can use to pay for mass transit — from $120 per month to $230 per month.

“This law nearly doubles the savings employees can enjoy by using mass transit and sets us on a path to a future that’s both economically and environmentally sustainable,” said Larry Filler, President and CEO of TransitCenter and one of the key drivers behind this provision.

Employers that participate in the program will benefit as well. Companies offering the benefit can save up to an additional $100 per employee per year in payroll taxes.

According to the American Public Transportation Association, switching from driving to riding mass transit reduces CO2 emissions by 4,800 pounds per person per year.