PORTLAND (AP) — Maine transportation officials say they are preparing for a shortfall in federal highway dollars that could begin in August.

The Portland Press Herald reported (http://bit.ly/1ohIcus ) federal highway dollars pay as much as 80 percent of the cost of Maine road and bridge projects. The federal Highway Trust Fund helps states pay for transportation projects and is expected to become insolvent by the end of the month without Congressional intervention.

The Press Herald reported it is unclear how Maine officials would deal with reductions in funding. The state received $165 million in federal funds in 2013.

The Highway Trust Fund is funded by the federal gas tax. The 18.4 cent-per-gallon tax hasn’t been raised since 1993.