Redeveloping San Diego's City Hall complex would be more expensive in the short term, but save the city money down the road, according to a financial evaluation released today.

The 51-page assessment was completed by the consulting firm Jones Lang LaSalle for the Centre City Development Corp.

Doing nothing and keeping the City Hall complex the same -- known as the "hold steady" plan -- would cost the city between $178 million to $217 million over the next 10 years, while redeveloping the Civic Center would be $204 million to $230 million over the same period, according to the study.

However, after 15 years it would be more cost-efficient to redevelop the City Hall complex, Jones Lang LaSalle's report found.

Over 15 years, it would cost the city $377 million to $417 million to do nothing, and $350-$376 million to build a new City Hall. After 50 years, the "hold steady" plan would cost San Diego $753-$790 million, compared to the cost of a new complex at $570 million to $596 million.

According to the study, the city would save between $12 million and $26 million by doing nothing over the next 10 years, but lose $26 million to $40 million in 15 years by not redeveloping the 1960s-era City Hall complex.

In response to the report, Councilman Carl DeMaio called on his colleagues to shelve the project.

"Today's updated numbers confirm our concerns that building a new City Hall complex will add to the city's financial difficulties in the next 10 to 15 years," DeMaio said. "At a time when the city faces structural budget deficits and looming liabilities in the pension system, the city should shelve this project."

Jones Lang LaSalle's report somewhat contradicts an early study that found it would cost less in the short-term to build a new City Hall than to remain in the existing buildings. Both analyses found significant savings by redeveloping City Hall in the long-run.

The Portland-based firm Gerding Edlen has been selected as the project's developer, if it ever moves forward.

Gerding Edlen has proposed replacing San Diego's aging City Hall with a 34-story, 964,000-square-foot glass and steel tower with an adjacent council chamber, parking, retail and public plaza.