Estimate the cost of adding a single lane to Arizona 1-19 in both directions from Nogales to 1-10 in Tucson. Do not consider stopping lanes or interchanges. ASSUMPTIONS 1. Entire roadbed is concrete 2. Neglect on and off ramps, bridge supports and railings, and emergency stopping lanes COLLECTED DATA 1. Concrete costs $125 per cubic meter delivered to site (estimate from contractor) Average depth of roadbed is 30.5 cm (Department of Transportation) Lane width is 3.6576 m (Department of Transportation) Length of 1-19 is 63.4 km 2. 3
. 4.​