Plow Route Cycle Time, Accumulation, and Truck Count

How long a plow route takes to come back around, how much snow lies on the ground when it does, and how many trucks a service level costs. CYCLE TIME IS THE SERVICE LEVEL AND EVERYTHING ELSE IS BOOKKEEPING. A customer or a council does not experience lane-miles or truck counts; they experience how deep the snow is when the plow returns, and that is the snowfall rate times the cycle. Every winter operations argument reduces to that one number, and stating the promise as a cycle time rather than as an effort is what makes it checkable. THE OVERHEAD FACTOR IS WHERE A PLAN MEETS A CITY. A truck does not plow at its plowing speed for the length of a route: it turns at the ends, slows through intersections, waits behind traffic, lifts the blade across crossings, and goes back for material. On an open highway route that overhead is small; on a dense residential grid with short blocks it can approach the plowing time itself, and a fleet sized on the map rather than on the route will be short. The factor carries the whole answer and has to come from the operation's own route timing records. THE FLEET SCALES INVERSELY WITH THE CYCLE TARGET, which makes service level decisions expensive in a very legible way. Halving the cycle time doubles the trucks, the drivers, the maintenance and the yard space, and it does so for a promise that is only tested a handful of times a winter. Stating the trade in inches -- what the tighter cycle actually buys, on the ground, at a given snowfall rate -- is what a public works budget is really deciding, and it is usually argued in trucks instead. AND A COLD EVENT LENGTHENS THE CYCLE WITHOUT ANYONE DECIDING TO. The material rate roughly doubles below 20 degF, which doubles the reload trips, and that time comes straight out of the cycle the standard was written around. This is a planning estimate on entered figures. It treats plowing speed as constant, which it is not: speed varies with snow depth and type, and deep or wet snow slows a truck substantially at exactly the moment the cycle matters most. It does not address the sequencing of routes by priority, which every real operation does and which means the lowest-priority streets have a cycle time far longer than any published standard, or the shift structure, hours of service limits and driver fatigue that govern a multi-day event. It does not address equipment availability and spare ratio, which is what actually determines how many trucks are on the road during a long storm. It takes no position on what service level is appropriate. The operation's own route timing records, the applicable hours of service provisions, and the public works or contract standard govern.

effective speed = plowing speed / overhead factor; cycle time = route lane-miles / effective speed; accumulation between passes = snowfall rate x cycle time; lane-miles per truck = effective speed x cycle target; trucks = system lane-miles / lane-miles per truck, rounded up.

Standard winter maintenance route and fleet sizing relations. The overhead factor is ENTERED from the operation's own route timing records; 1.2 to 1.5 is ordinary.

A rate relation and a division rounded up.

Estimate. AHJ and licensed professional govern.

Field names used by the API: route_lane_miles, plow_speed_mph, overhead_factor, system_lane_miles, cycle_target_hr, snowfall_in_hr, alt_cycle_target_hr, effective_speed_lane_miles_hr, cycle_time_hr, cycle_time_min, accumulation_in, lane_miles_per_truck, trucks_required, alt_lane_miles_per_truck, alt_trucks_required, extra_trucks, accumulation_bought_in

• Overhead factor is entered turns, intersections, traffic, blade lifts and reload trips; 1.2 open, 1.5 dense gridthe operation's own route timing records
• Constant plowing speed depth and snow type are not modelleda planning-level estimate
• No priority sequencing every route is treated as cycling on the same standardthe public works or contract standard