CARLSBAD -- The city could stop paying union-scale wages for large construction projects and change the way it buys office supplies under a proposal that the City Council will consider Tuesday.

Carlsbad has the ability to make these changes and others because it recently become a charter city and, as such, is allowed to exempt itself from some state laws. Voters approved the city charter June 3.

City officials have said recently that the proposed purchasing changes could save Carlsbad millions of dollars, but the proposal is likely to be opposed by construction union members. In the past, union advocates have said that failing to follow the state's prevailing requirement will hurt local families.

Tom Lemmon, business manager for the San Diego County Building and Construction Trades Council, couldn't be reached for comment Friday afternoon. His organization has sued the city of Vista, which is also a charter city, because it has refused to follow the state's prevailing wage requirement.

Carlsbad Attorney Ronald Ball said Friday that there is a difference between the two cities when it comes to the prevailing wage issue.

Vista states in its charter -- the document that guides the city -- that it won't follow the state's wage requirement. But Carlsbad is proposing simply to amend its ordinances to allow the City Council to determine whether to pay prevailing wages on a case-by-case basis, Ball said.

Most California cities are general law cities, meaning they are bound by state law and must pay state-determined prevailing wages -- essentially union-scale wages -- on municipal construction projects. They also must follow state requirements when it comes to how they purchase office supplies or other equipment.

Among the changes the council will consider Tuesday is a proposal to increase the dollar limit from $5,000 to $30,000 for what's considered "small procurements of supplies, services or equipment."

Purchases of less than $30,000 would not require formal price quotes, though "the best management practice would be to get three informal quotes for all items," the staff report states.

The changes would speed the purchasing process for many city items, it stated. From July 1, 2006, to June 30, 2007, about 90 percent of city purchase orders for non-construction projects were for things costing less than $30,000, the report states.

When it comes to the prevailing wage proposal, the city will face some limitations. Carlsbad will still be required to pay state prevailing wages for "projects which are of statewide concern, or if state or federal grants are paying for the project," the report states.

Road projects that receive grant funding would be an example, Ball said Friday. But the city's Alga Norte Park project would be exempt, Ball said.

When the council considers whether to pay the prevailing wage, it will look at a series of issues including the nature of the job, the availability of the local labor force and economic factors, he said.

"They're going to decide what's in the best interests of the citizens," he said.

Tuesday's meeting starts at 6 p.m. at City Hall, 1200 Carlsbad Village Drive.

For a copy of the report and other agenda information, visit the city's Web site at http://www.carlsbadca.gov/chall/4councilmtg.html