ECONOMIC FEASIBILITY OF EXCLUSIVE VEHICLE FACILITIES

A microcomputer program called "exclusive vehicle facilities" (EVFS) that determines the economic feasibility of separating light vehicles from heavy vehicles on a given section of controlled-access highway by designating existing lanes and constructing new lanes to be used exclusively by light or heavy vehicles is described. On the basis of user inputs to a spreadsheet user interface, EVFS calculates the net present value, benefit-cost ratio, and other performance measures of the alternative exclusive vehicle facility specified. The three possible lane use policies allowed within EVFS are mixed-, light-, and heavy-vehicle lanes. EVFS accounts for the following potential benefits or cost savings both for person and for freight travel: (a) travel time savings; (b) vehicle operating cost savings; (c) accident cost savings (fatalities, injuries, and property damage), because of less severe accidents by separating light and heavy vehicles; and (d) queuing delay savings because of fewer accidents causing blockages. EVFS also accounts for the following project costs: (a) initial construction costs, (b) initial right-of-way acquisition and demolition costs, and (c) periodic pavement resurfacing costs, which may be less frequent and less costly for light-vehicle lanes. EVFS is designed to evaluate any of the following five cases: (a) do nothing; (b) designate existing lanes for mixed, light, and heavy vehicles; (c) add mixed-vehicle lanes (no special lane use restrictions); (d) add non-barrier-separated lanes and designate new and existing lanes for mixed, light, and heavy vehicles; and (e) add barrier-separated lanes and designate new and existing lanes for mixed, light, and heavy vehicles. An example indicates that exclusive vehicle facilities are most warranted for congested urban highways with significant percentages of single-unit and combination trucks in the traffic stream.