More than 400 entities across the nation, including school transportation providers and associations, are urging Congress to provide funding for the Diesel Emissions Reduction Act (DERA) program.

The broad coalition — also including other transportation industry organizations and environmental and public health groups — sent letters to key committee members in the Senate and House asking for continued support of DERA, which was recently reauthorized but currently has no funding allocated for 2012.

"There are 20 million existing diesel engines in use today, and immense opportunities remain to reduce diesel emissions through the DERA program," the coalition wrote.

The organizations called for $50 million for the program for fiscal year 2012, the same level as in 2008. Also requested is support for President Obama's budget request of $305.5 million for state and local air quality grants for 2012.

The EPA has estimated that for every dollar spent on the DERA program, an average of more than $20 in health benefits is generated.

"Throughout DERA’s history, it has enjoyed strong bipartisan support, most recently demonstrated this past December when Congress took the extraordinary step of reauthorizing this important program during the lame duck session," the coalition wrote. "Without additional funding, the DERA program, and its environmental, public health, and economic and jobs benefits, will be in jeopardy."