A preliminary discussion about Carson City water service and sewer treatment fee increases left Mayor Robert Crowell skeptical about relying solely on fees.Crowell, after a staff presentation to the Board of Supervisors Thursday about projected multiyear fee hikes to cope with aging sewer treatment plant problems, urged consideration of an eighth-cent sales tax hike.“Why isn't that in the mix?” he asked. He made the point that tourists flush toilets in Carson City, not just residents. Crowell and supervisors were reacting to fee hike ideas projected at 3 percent annually on water, 10 percent on sewer service. The discussion was part of a wide-ranging special meeting on the fiscal year 2013-14 budget, which city staffers are drafting for supervisors' consideration in the spring.The board voted to keep property taxes unchanged at $3.56 per $100 assessed value based on a preliminary budget, with $58.7 million in basic general fund expenditures. Add $4.5 million in operating transfers — nearly $3 million of that debt service — and the total hit $63.3 million.Those preliminary figures involve keeping existing service levels, said City Manager Larry Werner, but the water and sewer discussion that followed sparked considerable back-and-forth over long-term impacts.Public Works Director Andy Burnham, saying parts of the sewage treatment plant are 50 years old, told Crowell he would take the money needed from whatever sources supervisors select.He said if fees are the exclusive method used to fix the sewer problem, they could rise 10 percent a year over a few years or 35 percent in a one-time hit. He also said Carson's fees are lower than those of surrounding cities.“We can't keep our treatment plant working without improvements,” Burnham said. Federal oversight requires compliance, he said.Supervisor Jim Shirk said it would be difficult for him to vote for anything that smacked of approving Burnham's ideas without seeing more specifics and hearing about a rate study in progress.That seemed in part what led Crowell to urge city staffers to consider the full discussion rather than seek from the board an explicit vote endorsing assumptions in Burnham's presentation.