Rising ferry fares and declining traffic are costing the economy millions more than the revenues accruing to BC Ferries, according to a study prepared for discussion at this month's local government convention.

Based on what it is calling the first ever "socio-economic" study of ferry use and costs, the Union of B.C. Municipalities executive is recommending the province reverse its November 2013 decision to continue raising ferry rates beyond the rate of inflation.

The report refers to passenger declines of 20 to 40 per cent on northern routes, 10 to 20 per cent on minor routes and five to eight per cent on major routes. The report finds that "ferry ridership declines run counter to the trend of transportation volume increases in most other modes of transport in B.C., including vehicle and air transport."

The report estimates that if fare increases had been kept to the rate of inflation, passenger volumes would have grown by 19 per cent over the past decade, adding $2.3 billion to the province's gross domestic product.

Transportation Minister Todd Stone and previous ministers have argued that ridership declines have been seen on Interior ferries that charge no fares, and on other travel affected by rising fuel prices.

The UBCM wants the provincial government to take a "pause" in rate increases set by B.C. Ferry Commissioner Gord Macatee.

Current rate caps allow for maximum increases of four per cent this year and 3.9 per cent in 2015.

The UBCM membership will debate the report and recommendations at its annual convention in Whistler Sept. 24.