A proposed partnership between Fairfax County and a developer to overhaul a Park and Ride is drawing fire in Reston, with critics blasting a closed process that has kept many details tightly under wraps.

The Reston South Park and Ride project would add as many as 145 dwellings and a parking garage of up to 665 spaces to a property of about 10 acres. Edgemoor Real Estate Services offered the project unsolicited in November 2005 under the provisions of the Public-Private Educational Facilities Infrastructure Act. The act allows information on many aspects of the plan to be withheld until negotiations are complete and, critics charge, until the project is close to approval. Key details such as the eventual number of homes and parking spaces and whether the county will sell the land remain unknown.