Surface Water Drainage – Understanding the Common Enemy Doctrine

As we move into the rainy season a frequent question that comes up deals with flooding caused by changes on a neighbor’s property and potential liability. Today, senior litigation attorney, Robert Enos, walks us through the first part of a multi-part article dealing with the common enemy doctrine as it relates to surface water issues.

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Surface Water Drainage – Understanding the Common Enemy Doctrine – Part 1
By: Robert J. Enos, Esq.

As we begin to head towards the rainy season (whatever that means here in California) common questions abound as flooding begins to occur. One such question that comes up frequently is “my up-slope neighbor re-did their landscape over the summer and now our yard is being flooded by the neighbors runoff – do we have a claim?” In short the answer is maybe and depends on a myriad of factors.

The “common enemy doctrine” recognizes the right to repel flood waters by obstructions merely defensive in nature but may not be invoked to justify an obstruction of or interference with the natural channel of the stream or a diversion of the flow of water in such channel. Stated in its extreme form, the common enemy doctrine holds that as an incident to the use of his own property, each landowner has an unqualified right, by operations on his own land, to fend off surface waters as he sees fit without being required to take into account the consequences to other landowners, who have the right to protect themselves as best they can. In other words, every owner for themselves.

Prior to 1966, California courts followed the civil law rule in both urban and rural areas. In the case of Keys v. Romley, the California Supreme Court decided that reasonableness of conduct should be determined under tort law, rather than real property concepts. Because it is incumbent upon every person to use reasonable care to avoid injury to adjacent owners, a failure to exercise “reasonable care” may create liability for the upper owner. The lower owner remains responsible to take “reasonable precautions” to avoid damage.

The difficulty in applying the Keys rule is determining what constitutes reasonable care or conduct. This is where the opinions of the owners clash because each sees the problem from their perspective and how high on the hill they find themselves relative to the other. Reasonable care is a question of fact for a jury or judge acting as the trier of fact and all of the relevant circumstances must be considered, such as amount of harm caused, the foreseeability of the harm that results, and the purpose or motive with which the defendant acted.

In a more recent decision, the California Court of Appeal clarified that traditional negligence principles do not apply where a discharge of surface water causes damage. To determine reasonableness the Courts, examine the following: First, if the upper owner is reasonable, and the lower owner is unreasonable, the upper owner prevails. Second, if the upper owner is unreasonable, and lower owner is reasonable, the lower owner prevails. Third, if both the upper and lower owners are reasonable, but the lower owner is damaged, the lower owner prevails. No mention was made about the fourth possible scenario of both the upper and lower owners being unreasonable.

After considering these legal principles, it is apparent that taking no action is the preferred course of conduct because liability for diverting surface water is derived from conduct that is ultimately found to be unreasonable. However, even if the upper owner acts reasonably in trying to protect his property, he can still be liable if the lower owner acts reasonably and incurs damage. If the upper owner has not changed the historical flow of surface water in any manner, then it is unlikely that a successful action can be brought based on a claim that the upper owner did not do something that the lower owner claims should have been done to prevent damage.

Communications with lower owners regarding mutual ways to protect each other’s land, and if possible, written agreements waiving liability for any preventive measures, should always be considered.

The attorneys at BPE Law Group have years of experience related to real estate issues that may affect your rights. No two situations are the same and each requires its own independent legal analysis of the facts. If you have a real estate or surface water issue the attorneys at BPE Law Group are hear to help.