There are 3 common causes for sewage backups.
- Inflow and infiltration (I/I) which is a technical term for holes or cross connections into a separated sanitary sewage system which allow rainwater to enter the separated sewage system causing pressure, surcharging and ultimately basement backups. Often governmental entities faced with citizen anger due to a sewage backup will claim that the event occurred because of an “Act of God” or a significant rain event. What these governmental entities almost universally fail to mention is that in most instances, the pipe that backed up into the residential property was a separated sanitary sewer system. This means that rainwater is not intended to enter the sanitary sewage system as there is a separate storm drain which has catch basins and is engineered to capture and convey rainwater runoff. In contrast, a sanitary sewer is only intended to convey the liquid created by ordinary household uses (toilets, showers, dishwashers, etc). As such, a separated sanitary sewer is much smaller than a storm drain. The decreased size means that when rainwater enters the sewage system, extreme pressure is created which relieves itself by backing up through the sewer lead which connects private property to the municipal sewer system.
Even where the governmental entity operates a combined sewer system in that the rainwater runoff and the sanitary sewage flow in the same drain a basement backup should not occur. Combined sewer systems typically have a combined sewer overflow (CSO) which, when the water reaches a certain level, is relieved by a direct discharge into a stream, river, retention pond or lake.
- Pump failures. For ease of maintenance, most sewer systems flow by gravity for miles until they reach a pump station which pumps or lifts the sewage to a higher elevation on its way to a discharge point or wastewater treatment plant. As all sewage arriving at the pump station has flowed via gravity, proper operation of the pump station is critical in that a pump failure will cause essentially a pile up or traffic jam of sewage which, if severe enough, will backup throughout the system causing surcharging and pressure which relieves itself by backing up into private property. For this reason, proper pump maintenance is critical. Additionally, it is well known that pump failures are likely to occur when pumps are most needed or when weather is severe. For this reason, governmental entities operating sewage systems are almost universally required to have backup generators or some form of independent power such that if an electrical failure occurs (which is more likely to occur during a heavy rain storm) the pumps continue to operate.
- Obstructions and debris caused by improper maintenance. Obviously, an obstruction such as root intrusion, the buildup of solids or other debris will impede the flow of sewage which will cause a sewage backup. To ensure that such maintenance issues do not arise, it is important that the governmental agency charged with operating the sewer system engages in regular cleaning and/or maintenance of the sewer system. Unfortunately, most governmental agencies do not even have written procedures regulating the maintenance of their sewer system.
The above causes are referenced as most governmental agencies faced with a claim of damages arising from a sewage backup will state that the backup occurred due to unforeseen circumstances such as an unusual rain event, pump failure or some form of obstruction. These claims do not automatically relieve the defendant of liability. It is well known that occasionally, we will have significant rain events and that pumps may fail and that if not properly cleaned, sewage systems will become obstructed. Governmental entities faced with claims for damages arising from sewage backups typically respond to such claims by issuance of a form letter outlining the severity of the rain event and the complexity of the sewer system. In Michigan, most of these letters typically also refer to the complexity of the Statute (MCL 691.1416 et seq) governing a claim of damages for a sewage backup. These letters are submitted in an attempt to bully and/or intimidate the victim of a sewage backup into accepting the governmental agency’s assertion that it is not responsible for the sewage backup and/or it would be too difficult for the homeowner to prevail. Do not be intimidated by these letters. Feel free to contact us for a free consultation regarding any such claim. In most cases litigated by this office, common sense ultimately prevails. Putting aside the law, from a common sense point of view, should a homeowner in 2012 in the United States of America be required to accept the presence of raw, untreated sewage in his home. The answer is clearly no.