For almost four years Montgomery County planners, working with homeowners, property owners and businesses, designed a vision for a new White Flint; a neighborhood crucial to the county's economic engine with close to 13 million square-feet of commercial space.

In the next few months, the County Council will have to figure out how to pay for the roads, parks, and other amenities required to further transform the Route 355 corridor in North Bethesda into a more urban hub.

That task is a priority for the County Council, which reconvenes in September, and will begin considering who will foot the bill for the $1.1 billion in projects included in White Flint's growth plans for the next 40 years. The projects include schools, emergency service stations, roads, and other infrastructure improvements.

"There's options to be considered here; a mix of public and private contributions to fund these projects," said Steven Silverman, director of the county's Department of Economic Development. "These are public amenities we're talking about, so they'll have to be paid for in the same way we pay for roads or anything else."

The White Flint Sector Plan, approved in March by the County Council, calls for a combination of financing mechanisms, such as a development district — an area designated with a temporary special tax on commercial and residential properties — added fees for certain developers and county funds, Silverman said.

The council will also need to address "the gap" in the proposed financing plans for White Flint, where roads are needed before taxes can be collected, county councilman Roger Berliner (D-Dist. 1) of Potomac said.

"If you want these facilities built early; in year one or year two or year three, before a lot of this money comes in, you're looking at a gap where the money hasn't come in yet," he said.

The first stage of the White Flint Sector Plan – slated to include significant upgrades to Rockville Pike, Main Street and Market Street as well as other improvements – will require between $70 million and $100 million to come from the development district alone and close to $100 million in infrastructure upgrades from developers, said Diane Schwartz Jones, assistant chief administrative officer for County Executive Isiah Leggett.

To cover this cost, an additional real estate property tax will likely be placed on commercial and possibly all residential properties in White Flint, she said. During the formation of the sector plan last year Maryland-National Capital Park and Planning Commission staff proposed the tax to be at least 10 cents per $100 of assessed value, a low figure by some estimates, Schwartz Jones said.

"No recommendation has come from the county executive yet, so we don't know what that figure will be or what it will need to cover," she said. "...When we looked at the outline given to us by [the M-NCPPC] there was still a gap that needed to be filled."

The county anticipates spending more than $70 million of its own money on the first stage, Schwartz Jones said.

A residential tax will not bode well with property owners, said Karl Girshman, who lives in White Flint.

"I think it would be horrible, especially now with the economy to add to our [property] taxes," he said.

Montgomery County is expected to get a significant return on its investment in White Flint, said Greg Trimmer, Senior Vice President of JBG Companies, which is building a 400-unit high-rise luxury apartment complex called North Bethesda Market on Rockville Pike.

Analysis done the county found that the new White Flint will bring $6.9 billion in tax revenue over the next 40 years.

"If you're talking about $490 millions spent; that's a significant return on investment I've heard of," he said.

The White Flint area is bounded by Rockville Pike, Montrose, and

Randolph roads in North Bethesda. Under the master plan, which was approved by the County Council in March and is a blueprint for the area over the next 40 years, 9,800 new residences and 5.49 million square-feet of commercial space would be added to an area populated by 18,720 people and with 5.69 million square-feet of commercial space.