The unstoppable oil boom in the U.S. is creating so much heavy machinery and truck traffic over roads in North Dakota and Texas that those states' road budgets are unable to keep up, and traffic accidents and drilling-state traffic fatalities have more than quadrupled since 2004, an Associated Press analysis and U.S. census data show.

Traffic fatalities and serious injuries increased 7 percent last year compared to 2012 in the Texan Eagle Ford shale fields, and fatalities increased 13 percent in the Texan Permian Basin oil fields, according to the Texas Department of Transportation. In La Salle County, Texas’s second-largest oil producer, car crashes more than doubled last year compared with 2003.

“Everybody is concerned about the number of fatalities,” La Salle County Judge Joel Rodriguez Jr. told Bloomberg.

In North Dakota, traffic fatalities decreased slightly last year from 2012 but have increased about 30 percent since 2007, according to data from the state’s Department of Transportation. In North Dakota’s drilling counties, traffic fatalities have increased 350 percent in the last decade, driven by a 43 percent surge in population, according to Insurance Journal.

“If you drive a cattle truck one or two times a year, you’re not affecting that road very much, but the first day you drive a 175,000-pound substructure of a drilling rig up that road you begin to destroy it,” Daryl Fowler, the county judge in DeWitt, Texas, told Bloomberg in May. “You’re looking at $2 billion of capital investment in our county alone that will be thwarted or curtailed completely if the road system is abandoned and they can’t get their product to market.”

In response, the country’s top oil-producing states are increasing their road construction and maintenance budgets. The Texas Department of Transportation is hoping residents will vote in November to allow $1.4 billion in oil and gas revenue to fund highway work rather than sit in a rainy-day fund. North Dakota’s Department of Transportation (NDDOT) has increased its road budget from $250 million a year in 2007 to $800 million a year, “making it one of the DOT's biggest years,” according to NDDOT media relations officer Katie Pizza. 

The rise in accidents and threat of crippled oil dollars is prompting state governments to seek ways to boost their road budgets.