United States: The Need For Off-Site Stormwater Easements In Pennsylvania

It is not uncommon these days for a question to arise as to the need for an off-site stormwater easement by the municipality or Department of Environmental Protection (DEP) as part of the design of the stormwater system for a new development project.  When this happens, an applicant needs to determine if they can redesign their stormwater system to avoid the need for this off-site stormwater easement or if they will have to approach one or more adjacent or area landowners to acquire a stormwater easement on their properties.  Obviously, in many cases, the former is much easier than the latter; particularly when one of those landowners from whom you would need a stormwater easement is either opposing your project or looking for a payday.  And I am not talking about the candy bar. 

In the recent case of Bretz v. Central Bucks School District, the Commonwealth Court attempted to "clarify" the law as to when an applicant needs an off-site stormwater easement.   Unfortunately, based on my reading of this case, the Court only "muddied up the waters" on this subject.  Some might attempt to argue that the Bretz case sets a "new and higher" standard as to when an applicant needs an off-site stormwater easement.  Some might also attempt to argue that an off-site stormwater easement is now needed any time an applicant has proposed to construct a stormwater basin and discharge the water from the basin either directly or indirectly onto an adjacent property.  In my opinion, such an interpretation would further complicate and frustrate the approval process when it comes to stormwater designs and would be contrary to the intent of the Pennsylvania Stormwater Management Act and other DEP regulations/design guidelines on the subject. 

In Bretz, the adjacent landowner appealed an Order of the Bucks County Court of Common Pleas that denied their request for injunctive relief concerning stormwater issues they were having as a result of recent and proposed improvements by the adjacent Central Bucks School District.  The landowner's 31-acre property is downstream from and adjacent to the District's 66-acre property containing a high school, middle school and related improvements.  The landowner filed a complaint in equity alleging that the expansion of the adjacent schools caused an increase in the volume and duration of stormwater discharge onto their property and resulted in long-term and continuous damage to their property.  According to the landowner, the detention basin, berm and 36-inch pipe installed by the District operated to decrease the rate of surface water flow onto their property, but substantially increased the duration of stormwater discharge from one to four or five days. 

At the hearing before the lower court, both parties presented expert testimony concerning the stormwater management undertaking during the District's construction.   Much of the testimony concerned whether the District violated the applicable subdivision and land development ordinance.   However, all parties agreed that, although the direction of water into the new detention basin decreased the rate of stormwater flow onto the landowner's property, it increased the total volume of water discharged.  The trial court determined that the landowner was not entitled to injunctive relief because they failed to establish a violation of the Township's subdivision and land development ordinance; and because the continued construction of the District's improvements will, in the future, reduce stormwater flow onto their property to pre-development levels. 

On appeal, the landowner argued that the trial court erred in holding that the landowner did not demonstrate an exception to the "common enemy rule" (i.e., the general principle that the law regards surface waters as a common enemy which every proprietor must fight to get rid of best he may) in determining that the District did not violate the applicable SALDO provisions and that the District's construction of a stormwater detention basin and a 36-inch pipe did not constitute an alteration of existing points, patterns or the location of natural drainage. 

In order to understand this issue, a historical review as to prior case law on the subject would be helpful.  In 1906, in a case titled Strauss v. Allentown, the Pennsylvania Supreme Court held as follows: 

The owner of upper land has the right to have surface waters flowing on or over his land discharged through a natural water course onto the land of another  . . . He may take proper and profitable use of his land even though such use may result in some change in quality or quantity of the water flowing to the lower land . . . from those rules it is clear that only where the water id diverted from its natural channel or where it is unreasonably or unnecessarily changed in quantity or quality has the land owner received an injury. 

In 1955, the Supreme Court restated the common enemy rule in the case of Leiper v. Heywood-Hall Construction Co., as follows: 

It is only where the owner of higher land is guilty of negligence which causes unnecessary damage to the servient owner, or where by an artificial channel, he collects and discharges surface waters in a body or precipitates them in greatly increased quantities upon his neighbor, that the latter may recover for any damage thereby inflicted. 

In this same case, the Supreme Court summarized the law on this subject as follows: 

A landowner may not alter the natural flow of surface water on his property by concentrating it in an artificial channel and discharging it upon the lower land of his neighbor even though no more water is thereby collected than would naturally have flowed upon the neighbor's land in a diffused condition.  One may make improvements upon his own land, especially in the development of urban property, grade it and build upon it, without liability for any incidental effect upon adjoining property even though there may result some additional flow of surface water thereon through a natural watercourse but he may not, by artificial means, gather the water into a body and precipitate it on his neighbor's property

In Marlowe v. Lehigh Township, in 1982, the Commonwealth Court, in reliance on the above authority, held that where surface water is artificially diverted or collected, a plaintiff sustains a cognizable injury if there has been an increase in the total volume of water discharged onto the land or if the volume remains unchanged but is "discharged with augmented force."  This Court also held that the legal wrong lies in the artificial diversion or collection of water itself, and made these pronouncements without regard to the degree in which the volume or force is increased per this Court:  "A plaintiff need only show that a landowner collected and/or concentrated surface water from its natural channel through an artificial medium, and the water was discharged onto the plaintiff's property in an increased volume or force; however slight." 

Then, in 1985, these principles were summary by the Superior Court in LaForm v. Bethlehem Township, which held that an upper landowner is liable for the effects of surface water running off his property in two distinct circumstances:  (1) where the landowner has diverted the water from its natural channel by artificial means; or (2) where the landowner has unreasonably or unnecessarily increased the quantity or changed the quality of water discharged upon his neighbor. 

In the Bretz case, in addressing the District's liability under the common enemy rule, the trial court determined that the increase in quantity of water was "reasonable," the installation of the detention basin and 36-inch pipe was "a proper and profitable use" of the District's land, and the water was discharged onto the landowner's property at the same place before and after construction.  However, the Commonwealth Court held that the trial court applied only the second standard set forth in LaForm (unreasonable or unnecessary change in quantity or quality), and overlooked the first standard (diversion from the natural channel by artificial means). 

Per the Commonwealth Court, the determination of whether a landowner "has diverted the water from its natural channel by artificial means" does not involve consideration of the reasonableness of the change in quantity or location of water flowing onto the lower land;   rather, to establish liability, a plaintiff need only show that a landowner collected and/or concentrated surface water from its natural channel through an artificial medium and that the water was discharged onto plaintiff's property in an increased volume or force; however, slight. 

In this case, the trial court specifically found the following as fact: 

  • The natural, physical contour leading to the landowner's property was a 60-foot-wide swale.  Due to the District's construction, the swale was replaced by a five to six-acre detention basin and a surrounding 15-foot high berm. 
  • The detention basin and berm collected additional surface water emanating from five to seven acres (and after the science wing measures two to four acres) of drainage area, which was diverted toward the Landowner's property as a result of the District's expansion projects. 
  • After collecting the additional surface water, the detention basin concentrated it to and through a 36-inch pipe, and the water intruding upon the landowner's property increased in terms of total volume and duration of discharge. 
  • A channel on the landowner's property eroded after the District installed a detention basin, 36-inch pipe, and berm. 

Accepting the trial court's findings as supported by the evidence, the Commonwealth Court concluded that the trial court erred in applying the "common enemy rule" to the facts of this case. 

As the Commonwealth Court has interpreted the law concerning the need for off-site stormwater easements, I cannot recall a project where an applicant did not construct a stormwater basin to collect the stormwater to reduce the rate of flow onto the adjacent property; however, in such case, the total volume of stormwater discharge was increased.  How can it not?  If additional improvements are being constructed, there will be more stormwater, there will be a need to contain that stormwater in a basin and then that stormwater must be released.  Last this author checked, stormwater continues to flow, like it or not, to the downstream properties.  An upstream property owner should not be prevented from discharging an increased volume of stormwater onto a downstream property if they have reduced the rate of runoff required by the municipality and DEP.  That is exactly what the Pennsylvania Supreme Court held in 1906 in the Strauss case in allowing a property owner to make a "proper and profitable" use of their land even though such use may result in a change in the quality or quantity of water flowing to the lower land.  The Commonwealth Court completely ignored the law established by the Supreme Court in Strauss; not to mention the Pennsylvania Stormwater Management Act and other DEP regulations/design guidelines on the subject.  This issue may need further clarification by the Supreme Court, the State Legislature, the Governor or DEP. 

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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