For all Illinois citizens, the winter season comes with an abundance of ice, sleet and snow. But for Illinois business owners, there is an additional threat: the potential for legal liability where someone slips and falls on business premises. According to data compiled by the Centers for Disease Control, in 2010 there were 9,146,026 nonfatal injuries in the United States that resulted from an unintentional fall. This statistic represents 29% of all injuries reported, and the number one cause of nonfatal injuries in the United States for that year. The cost associated with medical treatment for these falls is staggering, as the CDC reports medical costs of more than $59 billion. While these figures may seem intimidating, a savvy business owner armed with a basic understanding of Illinois law can take steps to minimize his or her potential exposure to personal injury suits.
The “Natural Accumulation Rule”
In Illinois, if an individual slips and falls on water, snow, or ice on the premises of a business, and later seeks to sue the business owner for his or her injuries, he or she will need to prove, among other things, that the business owed him or her a “duty”. In most cases involving water, snow, or ice, Illinois courts use the “natural accumulation rule” to determine whether a duty exists.
The natural accumulation rule states that an owner or possessor of land has no duty to remove natural accumulations of ice, snow, or water on its property. This proposition holds true without regard to how long the natural accumulation has existed on the property, or how long any precipitation has been ongoing. Although there is generally no duty, there are situations where a business owner may be held liable.
Even though no duty exists, businesses often undertake efforts to remediate snowy and icy conditions on their properties because such conditions represent a hazard to patrons and employees alike. Where a business opts to remediate, it can be held liable if it performs its removal efforts negligently. Where a business owners opts to remove snow, they still owe no duty with respect to any natural accumulations of snow or ice that lie beneath the removed snow. Liability may also exist where a business owner either aggravates a natural condition, or engages in conduct that creates a new, unnatural or artificial condition.
Much like the run off from an unnaturally accumulated snow pile, defects on a business’ premises can cause unnatural accumulations of snow, ice, or water. For example, consider a scenario where there is melting snow on a building rooftop. As the snow melts, water runs from the source into the gutter system where it is funneled from the roof through a downspout. So what if the downspout releases the water directly onto a sidewalk and it refreezes? A pedestrian that slips on the refrozen water would likely argue that the ice was an unnatural accumulation because it arrived there at the business owner’s direction, as opposed to a more natural means.
However, there are a number of examples where natural accumulations may be altered by human interaction, yet liability does not arise. One proposition commonly cited by the courts is that ruts or uneven surfaces created by traffic in snow or ice are not considered unnatural and do not form a basis for premises liability. In other words, simply traversing over a natural accumulation, to the extent that the ground becomes uneven and potentially dangerous for a later passersby, does not turn the natural accumulation into one that is unnatural. Similarly, courts commonly note that the simple act of salting a patch of ice, such that it melts and then refreezes, does not convert a natural accumulation of ice into an unnatural one.
A final example is that of tracked-in water. The common scenario concerns points of ingress and egress for a business that become highly saturated with water as a result of heavy foot traffic. Under these circumstances, courts consistently hold that landowners are not liable for injuries sustained by those who slip on tracked-in water. Rather, the tracked-in water is considered a natural accumulation that cannot form a basis for liability against the business owner.
The Bottom Line
The key to understanding what will or will not give rise to liability is to look at accumulations of snow, ice, or water and ask how the accumulation arrived there. A vigilant business owner can protect his or her business by taking notice of concerning conditions and remediating them before an accident occurs. Remediation efforts can be as simple as regularly salting a frequently icy area, or as drastic as re-routing a downspout to a flower bed or cold-patching a depression in a parking lot where water frequently pools. Even where preemptive measures are taken, however, slip and falls will occur, and business owners will need to defend themselves. Fortunately, the law promotes the maintenance of safe public environments by encouraging business owners to voluntarily undertake efforts to remediate potentially dangerous conditions even where there is no duty to do so. Illinois courts do not demand perfection from businesses concerning the removal of snow and ice, as doing so would make property owners the absolute insurer of the safety of their business invitees, which the courts have deemed unacceptable. For this reason, the natural accumulation rule exists to ensure that liability may be triggered only where an accumulation of snow, ice, or water is unnatural.
 This data is available to the public through the Centers for Disease Control’s online statistics database, WISQARS, which can be found at: http://www.cdc.gov/injury/wisqars/.
 Graham v. City of Chicago, 346 Ill. 638, 641 (1931).
 See Nowak v. Coghill, 296 Ill. App. 3d 886, 893 (2d Dist. 1998)(finding that the defendants created an unnatural accumulation when they shoveled the snow on their driveway into piles along the perimeter.) Although the defendants were ultimately found not liable, the court agreed that these piles could form a basis for liability if the facts had shown the defendants had knowledge that a particularly wide vehicle would be parking on the driveway that day. Id. Although Nowak involved residential owners, the same principals apply to commercial properties.
 Koziol v. Hayden, 309 Ill. App. 3d 472, 476 (4th Dist. 1999)(“Even when landowners voluntarily remove snow, they do not owe a duty to remove natural accumulations of ice underneath the snow.”) citing Watson v. J.C. Penney Co., 237 Ill. App. 3d 976, 978 (4th Dist. 1992).
 See Hornacek v. 5th Avenue Prop. Mgmt., 2011 IL App (1st) 103502 ¶¶ 31–32 (Sept. 30, 2011)(finding that a stream of water that ran off of a snow pile could constitute an unnatural accumulation that supports a finding of liability against the defendants.) In this case, the plaintiff presented evidence that the defendants had a habit of creating an excessively large snow pile in the corner of a parking lot. Id. ¶¶ 9–11. Throughout the day, the sun would melt the pile resulting in a stream of water that ran off and refroze elsewhere. Id. Plaintiff slipped on this stream of water and sustained injury. Id. The court found that the plaintiff presented sufficient evidence that she fell on an unnatural accumulation. Id. ¶¶ 31–32.
 Swartz v. Sears, Roebuck & Co., 264 Ill. App. 3d 254, 265 (1st Dist. 1993).
 Barber v. G.J. Partners, Inc., 2012 IL App. (4th) 110992 ¶ 25 (Aug. 8, 2012).
 Id. ¶ 26.