Montgomery County could spend more than $400 million to build a new White Flint, the latest figure to rise from the ongoing debate over funding the proposed new community.

County council members and developers used a series of hearings last week to debate just who will pay for the $1 billion in public amenities that underlie a plan to make the area an economic engine.

Financial analysts from the office of County Executive Isiah Leggett (D) unveiled the most specific list of infrastructure projects and their costs to date, sparking a discussion over the cost of the groundwork necessary for massive growth proposed in the area and concern that Montgomery County officials may not meet their end of the deal.

Earlier this month, Leggett proposed placing an additional property tax on certain areas of White Flint, the revenue of which would go directly toward such projects. It is expected to generate $208 million over the next 40 years.

Diane Schwartz Jones, the county's assistant chief administrative officer, said at Thursday's committee hearing that county council members still must answer the questions that loom over the plan, such as how much each stakeholder will be responsible for and how they plan to pay for projects before tax revenue can be collected.

Under the current plan, county and state agencies will pay $283 million in project costs, about 38 percent of the total cost of infrastructure. Through impact fees, developers are expected to foot about $257 million. These figures do not include the $130 million bus depot the county plans to build in White Flint.

Duchy Trachtenberg (D-At large) of North Bethesda and chairwoman of the Management and Fiscal Policy Committee, referred to White Flint as an investment for Montgomery County during the Thursday hearing, but said the council needs to proceed cautiously.

"We have to identify those [projects] that are essential, that are wished for, and that are unnecessary," she said.

aruoff@gazette.net