Fees associated with structure stabilization projects of varying degrees will take up about 55 percent of the spending on the U.S. 80 Bridge across the Mississippi River, according to the bridge commission’s budget approved this week.

Commissioners expect to spend $1,515,900 to continue stabilizing bulkheads and stop soil erosion on the Mississippi side of the river. Revenue from rail tolls, interest and other income will total $1,398,000. In the 2009-10 budget, tolls are projected at $100,000 a month — a mark not reached for a single month’s rail traffic since last August.

An independent audit under review by bridge commissioners shows the bridge’s deficit grew four-fold in fiscal 2009 as bridge repairs ramped up and rail traffic decreased due to the recession.

A draft of the study by The Halford Firm shows finances fell $568,268 into the red, more than the $180,756 deficit at the end of fiscal 2008. Rail tolls were off more than 13 percent over last year, while repairs to pier 2 surpassed $1.2 million during the past fiscal year, which ended June 30.

The five-member commission is expected to bring the audit up for formal adoption Sept. 9.