Source Water Protection Model Used to Evaluate Possible Pipeline Leak

American Water

Berks County, Pennsylvania

American Water is the largest investor-owned water and wastewater utility in the United States. 

In January 2013, a Pennsylvania American water system received an Underground Utility Line Protection Request (PA One Call) from Sunoco Pipeline to excavate around a petroleum pipeline to repair a possible leak in South Heidelberg Township, Berks County.  The system operates two high-capacity, public water supply wells within one mile of the reported pipeline leak.  Concerned that the possible leak may impact the water quality of the well, the operations manager for the system contacted SSM to evaluate the contamination risk and recommend preventive measures, if warranted.  

As part of an approved Source Water Protection Plan, SSM created a three-dimensional groundwater flow model to determine the direction and time-of-travel of groundwater entering the supply wells.  Within one hour of receiving the information of the possible pipeline leak, SSM’s lead computer modeler was able to determine a predicted groundwater flow path that a contaminant would take upon entering the groundwater aquifer.  The results of the model simulations showed that the two water supply wells closest to the incident would not be affected by a release of petroleum products into the aquifer.  However, a third groundwater supply well, located a mile and a half to the east, has the potential of receiving water that traveled from the location of the pipeline leak.  

Armed with this information, the Pennsylvania American system was able to develop a monitoring strategy designed to alert the system of potential water quality issues before it adversely impacts a source of drinking water supply.

Source Water Protection Plans are designed to be living documents that can assist the water system address possible water quality concerns.  The groundwater computer models used to develop source water protection plans can be used for ongoing planning and emergency response purposes.  By evaluating future predictive scenarios, water suppliers can be proactive in managing their water system.