Iowa Court Of Appeals Reiterates That Expert Testimony Is Necessary To Prove Liability In Flooding Cases

I’ve previously written about the need for expert testimony to support a property owner’s claims that flooding is being caused by an adjacent property owner’s land use. These types of claims seem to be increasingly common in Iowa. A recent Iowa Court of Appeals decision is a reminder that cases involving water runoff or flooding are often complicated and will usually fail without expert testimony to support the argument that the neighboring landowner is causing the water issues.

Homeowners in these situations often believe that they can prove the neighbor’s liability through an “eyeball test” and common sense. That’s simply not true. Iowa’s appellate courts have repeatedly made clear that proving responsibility in water runoff or flooding claims almost always requires an expert witness.

The Iowa Court of Appeals’s August 7, 2019 decision in Intlekofer v. Reitberry Rental Properties and City of Monticello is the most recent example of a water runoff/flooding case that failed because the plaintiffs lacked an expert witness to establish that the defendants’ use of their property was the cause of the homeowners’ issues. The Intlekofers claimed that the defendants had altered their properties in a way that caused flooding on their land and damaged their building. They sued the defendants for negligently causing the water runoff damage.

The Intlekofers did not retain an expert witness to testify about the topographical changes caused by the defendants’ land alterations and the corresponding impact on the water flow in the neighborhood. The city did retain an expert witness to testify in that regard.  The defendants sought a pretrial dismissal because the Intlekofers did not have an expert to connect the water issues on their property with the defendants’ property alterations. The Intlekofers responded that “[i]t is common knowledge that water flows downhill, not uphill. An expert is not necessary to establish such elemental propositions.” The trial court disagreed and dismissed the case because the Intlekofers lacked an expert witness.

On appeal, the Intlekofers faulted the district court for requiring them to secure expert testimony to prove that the defendants’ projects caused the water incursion. The court of appeals noted that the Intlekofers must prove that, but for the defendants’ wrongful conduct, they would not have incurred water damage. The Intlekofers insisted the defendants’ construction projects obstructed the downhill flow of water. They contended that no expert witness was needed to establish that law of nature.

The defendants contested the argument that the Intlekofers could proceed based only on claimed common sense assumptions about water flow. They contended that Iowa law does not allow a plaintiff to prove a negligence case involving this kind of water intrusion without expert testimony. The defendants said that was especially true when, as in this case, a defense expert has identified multiple other sources of water intrusion into the Intlekofers’ building.

The court of appeals agreed with the defendants. It ruled that, while it may be within the jury’s common knowledge and experience that water flows downhill, whether changes in topography caused water damage to a nearby building is a technical or scientific matter calling for an expert opinion. The court of appeals also observed that there was a defense expert that made the water intrusion issues even more complicated. The trial court thus correctly dismissed the Intlekofers’ case because, without an expert witness, they could not prove that the defendants’ alteration of their properties was the cause of the Intlekofers’ water issues.

The takeaway from this case is, again, that no matter how simple property owners may think their water runoff/flooding case may be, no matter how obvious they may think the cause of the water issues is, they’ll likely need an expert witness to support those theories. The failure to do so has resulted in dismissal after dismissal of water runoff/flooding cases under Iowa law. In short, property owners who attempt this kind of case without an expert witness to prove the cause of the water issues should assume that they’ll lose.