The Alexandria City Council approved a special-tax district on Saturday to help finance a potential new Metrorail station at Potomac Yard.

The council unanimously supported the tax district, which will go into effect on Jan. 1, 2011, on new developments within the Potomac Yard land mass.

Under current plans, the Metro station would be the cornerstone of a 7.5 million square foot new development containing mixed-use buildings and transitways. The station is projected to cost $240 million and city planners are unsure if substantial federal money can be secured. At the earliest, the station would open in 2016.

The approved tax district claims 20 cents per $100 of assessed value.

A second tax district is currently proposed but has met strong opposition by residents of the Potomac Greens community. The Tier 2 tax district would place a rate of 10 cents per $100 of assessed value on homeowners within the luxury townhome community. The City Council will discuss Tier 2 in the first quarter of next year.

Councilwoman Alicia Hughes reiterated Saturday that she is opposed to placing a tax on Potomac Greens residents. Councilman Frank Fannon and Hughes both said they opposed the tax district at a Nov. 30 public meeting where city officials discussed plans for Potomac Yard and alternatives in financing the proposed Metro station.