Skip Navigation LinksDEP > Businesses > Water > Bureau of Safe Drinking Water > Filter Plant Performance Evaluation > Questions and Info

Questions and Info

Purpose and Principles

In 1988, the Department of Environmental Protection (Department) initiated the Filter Plant Performance Evaluation (FPPE) program. At that time, Pennsylvania recognized the need for surface water systems to perform better than regulatory requirements. Waterborne disease outbreaks occurred at filtered water systems in other states even though the plants were in compliance with regulatory standards for turbidity. From 1971 to 1985, Pennsylvania reported more waterborne disease outbreaks that were related to drinking water than any other state in the nation. These disease outbreaks had devastating consequences for the affected communities. By contrast, no waterborne disease outbreaks associated with drinking water have occurred in the state since 1995, with the exception of a small outbreak in 2001 at a church camp using wells. Click on Waterborne Diseases Information Page for more details on outbreak trends.

The FPPE program uses a unique approach for a regulatory agency. For example, the program's recommendations are based on optimization of treatment rather than simply meeting regulations. An optimum level of performance minimizes the risk of a waterborne disease outbreak. Unlike most inspections that capture a "snapshot" of filter plant performance, FPPEs focus on a long-term picture of plant performance. In addition, FPPEs encourage optimization of each step in the treatment process and not just the combined filter effluent. This philosophy, combined with ambitious filter plant operators, has positioned Pennsylvania's filter plants for compliance with future regulations and the prevention of waterborne diseases. Pennsylvania is one of only a handful of states conducting these types of extensive filter plant evaluations.

What problems does the FPPE program address?

The FPPE program has helped solve these key problem areas:

  • In the Twentieth Century, waterborne diseases associated with drinking water were common, often leading to hundreds of deaths in the nation. Even in later years - from 1971 to 1985 - Pennsylvania reported more disease outbreaks associated with drinking water than any other state. Although these recent outbreaks were not as severe as the early-Century problems, diarrheal illnesses led to time off from work, school, or recreation, resulting in significant economic consequences.
  • Between 1988 and 2003, the number of plants increased from 204 to 349. Pennsylvania needed a special program like FPPEs to assist the growing number of water suppliers in enhancing the safety of drinking water.
  • Before 2003, Department staff rated the treatment plants as "Acceptable" or "Unacceptable" for their ability to remove disease-causing organisms. The FPPE performance rating system changed in 2003 to "Commendable", "Satisfactory" or "Needs Improvement." In 1988, the percentage of plants receiving an "Unacceptable" performance rating was at 39 percent, indicating an inadequate level of protection against waterborne diseases. They also were not prepared for more stringent regulations that were about to unfold on the state's water suppliers.
  • Operators at treatment plants use "turbidity" to measure the effectiveness of the treatment processes. Turbidity is measured as "NTU" (nephelometric turbidity units), or "cloudiness" of the water, and may indicate the presence of disease-causing organisms. In the early 1990's, violations of the 0.5-NTU turbidity standard were at an intolerable 7 percent of the plants. Likewise, the percentage of plants in violation of the 2.0-NTU standard was at an unacceptable 2 percent.

What are the most significant achievements of the program? Is evidence available to support these claims?

Pennsylvania's FPPE program has played a large role in correcting and preventing problems at surface water treatment plants. The following improvements have occurred in the state:

  • No waterborne disease outbreaks associated with drinking water have occurred in the state since 1995, with the exception of a small outbreak in 2001 at a church camp using wells. The U.S. Centers for Disease Control and the Environmental Protection Agency jointly released disease information in a summary titled, "Surveillance for Waterborne-Disease Outbreaks" published in a November 2002 Morbidity and Mortality Weekly Report [CDC Surveillance Summaries, November 22, 2002 / Vol. 51 / No. SS-8]. The summary showed no Pennsylvania waterborne disease outbreaks for 1997 and 1998, which follows a previous report that revealed no outbreaks for 1996 either. These reports typically lag two to three years while the agencies compile and analyze outbreak data from all fifty states.
  • The percentage of water treatment plants receiving a "commendable" or "satisfactory" performance rating has more than doubled. In light of new research indicating that a higher level of plant performance is necessary to remove pathogens, and in anticipation of more stringent regulations, the Department's on-site FPPE reviews have progressively become more rigorous in order to encourage systems to produce finished water quality that is better than current regulatory standards. When considering the more rigorous program standards, the current rating status shows a remarkable trend of improving filter plant performance in the state.
  • In Pennsylvania, between 1991 and 2001, violations of the 0.5-NTU turbidity standard declined to 0.3% of 349 surface water treatment plants in the state. In addition, the percentage of plants in violation of the 2.0-NTU standard has dropped to zero. NOTE: In 2002, the turbidity standard entered a transition period for plants serving various population sizes. Between 2002 and 2004, the new standards decrease to 0.3 NTU and 1 NTU for many plants.

Is the FPPE program getting tougher?

In light of new research indicating that a higher level of plant performance is necessary to remove pathogens, the Department's on-site FPPE reviews have progressively become more detailed over the years. FPPE recommendations are intended to assist water system staff by providing suggestions that can further improve plant performance. As a result, operators and plant superintendents may have seen a greater number of recommendations in recent FPPE reports. An increase in the number of recommendations is not necessarily an indication that plant performance has deteriorated.

FPPE recommendations seem like requirements since they are coming from the DEP, which is a regulatory agency. Is this a compliance-based program?

The FPPE program is an optimization program and there are no plans to make the FPPE program a compliance program. The recommendations in the FPPE report are not requirements. Water system staff are encouraged to review the Department's comments and consider which recommendations would improve plant performance. However, violations of Pennsylvania Safe Drinking Water Regulations are sometimes discovered during the FPPE. If the violation is a performance-limiting factor, it will be listed in the FPPE report with the other recommendations. The Department's inspector that is assigned to the water treatment plant will be informed of the violation. The inspector assigned to the plant will handle any follow-up action to ensure that public health is protected.

Click Testimonials Page to read what water suppliers say about the FPPE program.

Is the FPPE program adopting the goals of the Partnership for Safe Water program?

Although many of the FPPE and Partnership for Safe Water optimization goals are the same, the FPPE program has been around longer and has used optimization goals before the Partnership program was created. The FPPE program has recommended for plant personnel to set optimization goals since 1988. Since 1990, the FPPE program has recommended in FPPE reports for plants to meet the 2.0 NTU settled turbidity goal and to strive to maintain filter performance below 0.1 NTU. As early as 1991, the FPPE program concepts were published in national AWWA conference proceedings, which promoted lower, optimum finished water turbidity goals. Later, national organizations representing the drinking water industry as well as state and federal regulatory agencies developed the Partnership. The Partnership program was opened for membership nationwide in October of 1995. In addition, FPPE staff were a key resource for Partnership advisory groups and the development of the 1997 Self-Assessment Guide for Surface Water Treatment Plant Optimization (American Water Works Association Research Foundation). Similar optimization goals have also been published in an EPA Handbook called Optimizing Water Treatment Plant Performance Using the Composite Correction Program, 1998 Edition.

It seems like plants in Pennsylvania receive an FPPE more frequently. How often do the plants undergo an FPPE?

Historically, two Department staff members took the lead on all of the FPPEs in the state. Since 1999, the program has been de-centralized. Currently, 1 or 2 people in each of the Department's regions are conducting FPPEs. As a result, FPPEs in many regions of the state may occur more frequently. The actual frequency may vary from region to region based on the number of FPPE staff and filter plants per region. Currently, the state average is about every three to four years.

What about the water supply sources for filter plants - aren't they important too?

For the most part, the Department's watershed protection efforts are also outside the scope of an FPPE. However, it is included as a minor part of the FPPE protocol because total optimization at the treatment plant starts with, and is significantly aided by, protection and management of the source water. Through the Source Water Assessment Program, Pennsylvania is assessing the water quality of its more than 14,000 drinking water sources (both ground and surface water) serving public water systems.

From a safe drinking water and public health perspective, source water quality is important for the following reasons:

  • Under the Long Term 2 Enhanced Surface Water Treatment Rule (LT2), EPA has recognized that Cryptosporidium in surface water sources is a public health threat.
  • Reducing pathogen concentrations in source waters will help prevent waterborne disease outbreaks and perhaps reduce instances of endemic waterborne illnesses.
  • Under LT2, a high Cryptosporidium concentration in the source water may substantially increase the construction and long-term operation and maintenance costs for installing ultraviolet light, ozone, membrane filtration and other expensive technologies.
  • When compared to implementing more stringent requirements for numerous point and non-point sources of pollution, it might appear easier to require water suppliers to install additional treatment under LT2. However, a waterborne disease outbreak could sicken millions of people and require expensive and time-consuming responses from numerous businesses, homeowners, and state and local government.
  • Even "state of the art" treatment at a water supplier provides no guarantees -- a treatment breakdown due to equipment failure or human error represents an on-going threat when the source water is highly contaminated.

How do I learn more details about FPPE procedures?

Go to DEP's eLibrary to access the Department of Environmental Protection's full FPPE protocol.

How can I find more information on FPPEs?

For more information, please contact the DEP - Drinking Water Program at 717-772-4018. You may also wish to contact the FPPE staff person in your region of the state by going to the Contact Us page.