RES 00059 - Laserfiche WebLink

7. Updated Recommended Improvement Plan . 1.680 North The section north of Diablo Road cannot be widened beyond the HOV lanes without overcoming several significant constraints: the widening would require additional right-of.way, construction of new retaining structures, and the costly recon- struction of existing overpasses and undercrossings, as well as increase impacts on ad- joining land uses. The gateway constraint assumption recognizes these constraints. . 1-680 South The section south of Route 84 has room to be widened, and limited wid- ening would help accommodate and balance increased flows into this section from both 1-680 and the new in Route 84 project. Accordingly, the plan recommends the addition of HOV lanes. Gateway constraints would still apply for single.occupant vehicles. . 1-580 West The topographic constraints along the Dublin Grade and the limits im. posed at the 1-680/1-580 interchange make widening beyond the current four lanes prohibitively expensive. The 1997 opening of the Dublin - P!easanton BART line pro. vide a new alternative to vehicular use of 1~580. The Plan relies on the BART to pro- vide needed additional capacity through the gateway. . 1-580 East (Altamonl Paul Alameda County policy, in recognition of the need to encour- age shorter commuter trips and not overload Tri-Valley roads with regional traffic, op- poses increases to capacity for single-occupant vehicles across this gateway. The gate- way constraint policy also applies to Patterson Pass Road, Tesla Road and Old Altamont Road. Thc plan, however, includes HOV lanes, as a second-priority project, in recognition of the importance of 1-580 as a regional facility. The Plan also relies on and supports the continuation of the recent Altamont Commuter Express (ACE) service across this gateway. . (row (anyon Road (to (ostro Volley) Safety improvements are planned for this section of Crow Canyon Road, although. the TVfC supports maintaining the two-lane cross- section. . Vasco Road While the TVTe supports Vasco Road remaining a two~lane road, the Plan includes safety improvements to this roadway. Any future upgrade should be done in such a manner to not preclude future accommodation of public transit or othcr im. provements as subsequently determined appropriate. The plan is based upon the following set of assumptions regarding gateway capacity on the freeways and major arterials that access the Tri-Valley: . 1-680 North Six lanes plus HOV lanes . 1-680 South Six lanes plus HOV lanes 18 April 2000 Page 15 1