When Salt Lake City taxpayers voted in 2003 to bond for $10.2 million toward construction of an interactive science and art center known as The Leonardo, they were told organizers would raise the balance of the costs privately, estimated at another $10 million, before the bonds were issued. We agree with members of the City Council who say they are reluctant to now give any more tax money to cover unexpected expenses.

The Leonardo is scheduled to remodel the city's old library building for the center, and that is to include a seismic upgrade. But organizers say the cost of construction has risen since the bond election three years ago, and they have asked the city for an additional $1.5 million, which they would match with more private donations. They also prefer a more expensive renovation process that includes adding an interior wall and an 11,000-square-foot addition to the north end, linking Leonardo with the city's new library.

But there are limits to what the public should have to bear, regardless of how worthwhile a project may be.

For the record, we were opposed to the bond three years ago when it came before voters. It was part of a group of six projects on the ballot that year that included additions and renovations to the Hogle Zoo and the Tracy Aviary, three new library branches, the purchase of land for open-space preservation and a large soccer and baseball complex. Leonardo, we felt, was the least deserving of these. Voters felt otherwise.

As an alternative, some are suggesting the city's redevelopment agency could provide $750,000, contingent on $3 million in private fund-raising from Leonardo. Even that seems a bit much. Redevelopment money still impacts taxpayers, even if the impact is less immediate.

We don't doubt the value of the plans Leonardo organizers are touting for an interactive museum that, like its namesake, Leonardo da Vinci, would combine art and science in ways that could inspire the minds of both young and old.

But when voters approved a property tax increase to fund a portion of the project, they were led to believe they had satisfied their obligation. Even if an extra donation of city funds would not directly lead to a tax increase, it still would impact city coffers. Leonardo needs to make do with what it has, raising money on its own for any additions.