streets, all planned to open by 1985 and operated by the Municipality of Metropolitan Seattle. Seattle voters were asked to provide $385 million (equivalent to $ in dollars), to supplement a $765 million grant (equivalent to $ in dollars) from the Urban Mass Transportation Administration (UMTA), during a municipal election on February 13, 1968, narrowly passing the bond by 50.8%, but falling short of the required 60 percent supermajority. A second attempt on May 19, 1970, with an adjusted $440 million local contribution (equivalent to $ in dollars) and $881 million federal grant (equivalent to $ in dollars), failed to pass with only 46% approval amid a local recession caused by layoffs at Boeing; the earmarked funds intended for the Forward Thrust rapid transit project were instead allocated to Atlanta, to build its rapid transit system. Bus tunnel proposal and approval The concept of a downtown bus tunnel was first proposed in 1974 during discussions between Governor Dan Evans and Seattle Mayor Wes Uhlman about regional transportation projects in response to the proposed extension of Interstate 90 into Seattle via a third floating bridge crossing Lake Washington. Metro Transit later commissioned a study into the bus tunnel, released the following July, which determined that it would not be able to adequately meet the rush hour demand of downtown bus ridership by 1980. The study suggested that a double-decked tunnel with automated guideway transit to complement bus service, running from Union Station to the Seattle Center, would be able to meet projected demand at an estimated cost of $450 million. Ultimately, the plan was rejected because of the high cost of ventilation for diesel buses that would use the tunnel. The bus tunnel proposal resurfaced in 1979, outlining a tunnel from South Jackson Street to Pine Street that would carry 200 buses an hour in each direction at a cost of up to $350 million with the option of conversion for electric rail transit in the future. The tunnel was suggested by Metro officials and engineering consultants Parsons Brinckerhoff as a solution to worsening downtown traffic, and was better received than alternative concepts. The proposal gained further support from Metro Transit in its long-term "Metro 1990" plan, adopted in 1981, as a transit mall or tunnel under 3rd Avenue carrying buses that could be converted for a light rail system. The Puget Sound Council of Governments (PSCOG), a regional planning agency,