While selection of a new Jazz arena site is scheduled for Thursday, some say the location is already chosen - and it could cost millions of dollars more than taxpayers have been led to believe.

The Salt Lake Redevelopment Agency, in consultation with Jazz owner Larry Miller, is scheduled to decide April 6 whether $20 million in tax dollars will be spent to buy land on a northern or southern downtown site for the arena.The northern site, or site A as it is called, on Block 79 is bound by South Temple, First South, Third West and Fourth West streets, while the southern site, or site B, on Block 50 is bound by Third South, Fourth South, West Temple and Second West streets.

RDA officials have said both locales have an equal chance of becoming a site for the new arena. But some developers believe the RDA has already chosen site A, which could cost taxpayers $10 million to $20 million more in traffic improvements.

"It's skewed to the north," said one developer, because the southern site was left out of the RDA's taxing district in a bill passed this year by the Legislature. The developer spoke only on the condition he not be identified.

The southern site is not within the 100-acre area on which the RDA can collect tax increment revenue, meaning $16 million instead of $20 million would be generated to pay off the $20 million bond to buy arena land.

The southern site's poor ability to generate revenue to pay for land bought and then leased for $1 a year to Miller makes it an unlikely candidate for a new arena, leaving the northern site as the only alternative, developers say.

However, the northern site would require $10 million to $20 million in street improvements on Fourth West, Fifth West and on the Fifth South and Sixth North I-15 interchanges, according a county feasibility study.

The southern site, on the other hand, could withstand increased traffic created by a new arena, said George E. Patience, assistant division manager for DMJM planners and author of the study, which recommended a southern arena site.

"Any short-term (traffic) overload caused by the arena at site B (the southern site) would be tolerable compared to site A (the northern site)," he said.

Those cost figures and other issues favor the southern site, city Planning Commission Chairman John Schumann said.

"I favor site A and site B, but I think we'll get more for the money with site B," he said.

RDA officials say they have yet to consider the ramifications of necessary traffic improvements at either site.

"We have not gone into that aspect of it," said RDA Executive Director Mike Chitwood, "although we feel that at an appropriate time the city will be advising us as we move through this project."

City Transportation Engineer Tim Harpst said traffic improvements are only a single part of the arena package, and although the southern site is better "from an access viewpoint," it has other, traffic-related shortcomings.

Harpst said he will request a traffic study for the chosen site. "What needs to be found out is what those impacts are, how much they'll cost and who's going to pay for them."

Chitwood denied that the RDA has already selected a site for the Jazz, saying both sites have equal footing in the race for the arena. What's more, the RDA will not even consider whether a site is inside their tax district when the chose a site (see chart for what the RDA will consider).

Assistant RDA Director Dick Turpin told the RDA recently the southern site could be cheaper than the northern site, lessening the impact of the $4 million less the southern site will generate in tax increment.

Tax increment is the difference in taxable value between a property before and after it is developed. The RDA collects tax increment to use in assisting development of targeted blight areas.