multiple factors determine the number of deer-vehicle crashes in different Virginia jurisdictions, including the size of the county/city, the density of the deer population in each jurisdiction - and especially the number of drivers on the road during the times when deer are most active (8 of the top 10 are in suburban areas of Northern Virginia, Richmond, and Hampton Roads)
Source: InsideNOVA, By the numbers: Deer-related crashes in Virginia (2013)
Vehicle accidents involving deer are common throughout Virginia, in urban as well as rural areas. Statewide there are roughly 50,000 deer-vehicle crashes, putting Virginia in the "top 10" states with this problem.
Deer-car collisions are especially common in suburban counties, which have a combination of many deer and many drivers commuting to work at dawn and dusk. Fairfax County alone has 4,000-5,000 deer-vehicle collisions annually, with 55% occurring in the last 25% of the year. Statewide, 50%-66% of vehicle-deer collisions occur during the October-December rut season, when deer have other things on their mind besides avoiding traffic.1
deer-related accidents in Prince William County occur in developed suburbs and even on I-95, not in just the rural areas
Source: TREDS (Traffic Records Electronic Data System) (2016 data)
After an accident, the Virginia Department of Transportation (VDOT) removes deer carcasses from the roadway. The dead deer are not just dragged off of the pavement to the nearest ditch; that would attract vultures and other animals, and potentially cause more animal-vehicle collisions. Carcasses have been buried if there was a suitable location in a nearby VDOT right-of-way and equipment for digging a hole was available. Otherwise, the remains of the deer may be hauled away to landfills. By 2011, landfill disposal was costing VDOT $4 million a year in transportation and landfill fees.
Deer hit by a car (roadkill) or hunted illegally (poached, and butchered for the meat)
To reduce those costs, VDOT started to mimick a practice used on large farms and began composting animal carcasses. In one research test, dead deer were mixed in with woodchips and placed in static compost windrows ("passively aerated stationary piles") aligned on the ground surface. High temperatures within the piles of decomposing wood chips killed pathogens and roundworms in the carcasses within three months. In contrast to burying deer in the right-of-way, composting minimized the potential of bacteria reaching nearby streams and degrading local water quality. However, the windrows used up substantial space at VDOT's equipment centers.
To solve the problem in less space, the state transportation agency also experimented with a rotating drum composting system filled with sawdust and carcasses. A third technique was to place wood chips and carcasses in a rectangular metal bin, with a forced-air system. The fans recycled leachate droplets created as layers of carcasses rotted, and controlled odors by blowing the vapor back into the bin.
The rotating drum system had equipment problems and had difficulty maintaining desired the temperature and moisture, so VDOT decided to build forced air composting systems at multiple locations across the state. Those composting facilities cost $140,000 each, but costs were offset within five years by the reduced expenses for transporting and disposing of deer carcasses at landfills.2
In Virginia, cities rather than VDOT maintain most highways. The cities of Suffolk, Portsmouth, and Virginia Beach chose to use diesel-fueled incinerators, rather than compost deer killed in collisions with vehicles. The incinerators eliminated problems with any odor and leachate from decay. The Virginia Department of Environmental Quality had to issue air quality permits for new incinerators burning diesel oil, but Suffolk failed to get its emissions permit in time. In 2015, the General Assembly had to pass a special bill to give Suffolk additional time to meet state air quality standards.3
VDOT selected a forced air composting system for disposal of deer carcasses
Source: Virginia Center for Transportation Innovation and Research, Composting Animal Mortality Removed From Roads: A Pilot Study of Rotary Drum and Forced Aeration Compost Vessels