Please complete the tables below using the information provided.
Case Problem 15.2 It's Snowing Again! Gastonia, North Carolina, is not accustomed to significant snowfalls. In the past few years, however, the snow has been relentless. Determined to be prepared this year, the city manager has requested a capacity plan from GDOT (Gastonia Department of Transportation). The roads for which the city is responsible include 10 miles of 6-lane highways, 25 miles of 4-lane primary roads, and 50 miles of 2-lane secondary roads. The standard coverage for keeping roads clear during inclement weather is three passes over highways during a 12-hour time period, two passes over primary roads, and one pass over secondary roads. Gastonia has 10 snowplows with a maximum speed of 35 mph that can clear a width of one lane at a time. During a 3-in, snowfall, the plows are run- ning at 90% efficiency. The efficiency (measured by speed) decreases with the amount of snowfall to 75% during a 6-in. snowfall. 50% for a 1-ft snowfall, and 30% for a 2-ft or greater snowfall. During a normal 8-hour day, workers take one hour total for breaks and lunch. The same ratio is used for 12-hour shifts. This downtime is especially important during inclement weather, as the drivers need to warm up and refocus, and excess snow and salt needs to be removed from the equipment. Prepare a snow removal capacity plan for Gastonia roads that includes: a. An estimate of the capacity to clear roads in a 12-hour period ex- pressed in miles per type of snowfall (3 in, 6 in., 1 ft, and 2 ft or greater). b. An estimate of the total work load (in miles traveled) over a 12-hour period to keep roadways clear, and per type of road (highway, primary and secondary). c. An estimate of the current load percent, and a recommendation for adjusting the work load when load percent exceeds 100%. d. Three alternative recommendations for improving service by ex- panding capacity and/or reducing the workload. (Budget limitations would allow at most the purchase of five extra snowplows). What ad- ditional information would you need to make an informed decision? Capacity (miles) a. Efficiency Utilization Hours # Plows Mph Snowfall 3" 6" 1 > 2 0 0 0 4-lane 3-lane Highways Highways 2-lane Primary roads 1- lane Secondary roads b. Miles Lanes Passes Total mile Initial 0 0 0 0 0 C. Snowfall 3" 6" 1 > 2 Capacity (miles) 0 0 Load 0 0 Load 96 #DIV/0! #DIV/0! #DIV/0! #DIV/0! 0 0 0 d. Capacity (miles) Load percent Snowfall Efficiency Utilization Hours #Plows Mph 0 0 3" 6" 10 > 2 #DIV/0! #DIV/0! #DIV/0! #DIV/0! 0 0 Case Problem 15.2 It's Snowing Again! Gastonia, North Carolina, is not accustomed to significant snowfalls. In the past few years, however, the snow has been relentless. Determined to be prepared this year, the city manager has requested a capacity plan from GDOT (Gastonia Department of Transportation). The roads for which the city is responsible include 10 miles of 6-lane highways, 25 miles of 4-lane primary roads, and 50 miles of 2-lane secondary roads. The standard coverage for keeping roads clear during inclement weather is three passes over highways during a 12-hour time period, two passes over primary roads, and one pass over secondary roads. Gastonia has 10 snowplows with a maximum speed of 35 mph that can clear a width of one lane at a time. During a 3-in, snowfall, the plows are run- ning at 90% efficiency. The efficiency (measured by speed) decreases with the amount of snowfall to 75% during a 6-in. snowfall. 50% for a 1-ft snowfall, and 30% for a 2-ft or greater snowfall. During a normal 8-hour day, workers take one hour total for breaks and lunch. The same ratio is used for 12-hour shifts. This downtime is especially important during inclement weather, as the drivers need to warm up and refocus, and excess snow and salt needs to be removed from the equipment. Prepare a snow removal capacity plan for Gastonia roads that includes: a. An estimate of the capacity to clear roads in a 12-hour period ex- pressed in miles per type of snowfall (3 in, 6 in., 1 ft, and 2 ft or greater). b. An estimate of the total work load (in miles traveled) over a 12-hour period to keep roadways clear, and per type of road (highway, primary and secondary). c. An estimate of the current load percent, and a recommendation for adjusting the work load when load percent exceeds 100%. d. Three alternative recommendations for improving service by ex- panding capacity and/or reducing the workload. (Budget limitations would allow at most the purchase of five extra snowplows). What ad- ditional information would you need to make an informed decision? Capacity (miles) a. Efficiency Utilization Hours # Plows Mph Snowfall 3" 6" 1 > 2 0 0 0 4-lane 3-lane Highways Highways 2-lane Primary roads 1- lane Secondary roads b. Miles Lanes Passes Total mile Initial 0 0 0 0 0 C. Snowfall 3" 6" 1 > 2 Capacity (miles) 0 0 Load 0 0 Load 96 #DIV/0! #DIV/0! #DIV/0! #DIV/0! 0 0 0 d. Capacity (miles) Load percent Snowfall Efficiency Utilization Hours #Plows Mph 0 0 3" 6" 10 > 2 #DIV/0! #DIV/0! #DIV/0! #DIV/0! 0 0
