United States of America, Plaintiff,


Massachusetts Water Resources Authority ( MWRA) and

Metropolitan District Commission (MDC),Defendants.

Civil Action No. 98-10267-RGS

         Go to:
 Day-by-Day Account of the Trial
 Summary of Decision
 Full Court Decision 72 pages (PDF)

This summary was prepared by Nancy C. Kurtz, Associate General Counsel at MWRA. For further information, contact Nancy Kurtz at (617) 788-1145 or nancy.kurtz@mwra.state.ma.us

On May 5, 2000 U.S. District Judge Richard G. Stearns issued his decision on the 24-day trial held in the EPA enforcement action to require MWRA to include filtration in its new treatment plant. Judge Stearns found that MWRA is currently in compliance with all eleven federal criteria for avoiding filtration under the Surface Water Treatment Rule of the Safe Drinking Water Act. He evaluated the current quality of MWRA water and found the MWRA’s integrated drinking water improvement program including ozonation treatment technology the better approach to "preserving its safety." He found EPA failed to show that filtration of MWRA water was required either as a matter of cost-benefit or scientific necessity. The Judge denied EPA’s request for injunctive relief and ordered MWRA to give the Court notice of any future violations of the avoidance criteria. No other order was issued.

Agreeing with MWRA’s holistic approach, Judge Stearns evaluated Wachusett water quality in the context of the historic design of the system, the strides made in watershed protection through land use control and land acquisition, construction of sewers, and gull harrassment, the role of distribution system improvements including covered storage and pipeline rehabilitation, and recent treatment enhancements. He followed the federal filtration avoidance criteria as a "useful benchmark for measuring water quality." The opinion discussed the scientific arguments presented by each side, evaluating the competing opinions of experts based on their credibility, expertise and empirical support for their opinions.

Some highlights of the Court’s 72 page decision and the 35 ultimate conclusions of fact and law on issues of interest include:

Source Water Protection

Judge Stearns recognized the unique legacy — well-protected, high quality source water in large reservoirs — given to the MWRA system by the foresighted engineers who designed the system at the turn of the last century, noting their explicit intent to avoid filtration. He highlighted the importance of the watershed approach in preserving that legacy:

"There are no issues affecting the quality of Quabbin Reservoir water."

"The Wachusett Watershed Protection Plan, as conceived and implemented, has been effective in maintaining the integrity of the watershed as a barrier against contamination of the Wachusett Reservoir."

"I find credible the testimony of MWRA officials that the installation of filtration will diminish public support for the Watershed Protection Plan and will lead to increased public pressure to open restricted [watershed] lands to general recreational uses."

Scientific Evidence on Treatment Issues and Public Health

Judge Stearns viewed this case as one to be resolved based on scientific facts. He crafted his findings based on the scientific evidence presented in the 24 days of testimony and tens of thousands of pages of trial exhibits. He commented that burdens of proof, while working well in resolving most legal disputes, do not easily lend themselves to the resolution of scientific controversies. In his decision he relied on facts that he found fell within a reasonable range of possibility, recognizing that "science, by and large rejects binary decision making in favor of a more nuanced quest for understanding." The facts he found were in large part those propounded by MWRA’s witnesses, whom he found well-qualified and credible. Many of the facts were agreed to or uncontroverted by EPA’s witnesses.

"There is no present threat posed by Cryptosporidium to the quality of Wachusett Reservoir water."

"The MWRA has instituted an effective surveillance program to detect Cryptosporidium and other potential future threats to the safety of its drinking water."

MWRA’s new ozonation plant will effectively address Cryptosporidium and "emerging pathogens," enhance MWRA’s existing capacity to inactivate Giardia and viruses, and reduce the levels of disinfection by-products in MWRA finished water.

MWRA is in present compliance with all federal criteria for avoiding filtration, "a useful benchmark for measuring water quality," although "[f]ecal coliform bacteria are poor predictors of the presence or concentration of pathogens in water."

MWRA’s ozone design was based on well-supported, careful scientific studies, addressed "the most extreme limiting conditions (temperature and flow) that the plant can be expected to encounter," and contains appropriate capacity and redundancy to treat MWRA water under all anticipated conditions.

While ozone increases biodegradable matter which serves as "food" for bacterial regrowth in pipes, Judge Stearns found the most rigorous study on this issue was the one conducted by MWRA’s expert, Dr. Ann Camper, and he adopted her view that corrosion control, flushing and pipe replacement are more effective means of combating regrowth of bacteria in the MWRA distribution system than is filtration.

Judge Stearns relied on the risk analysis performed for MWRA by Dr. Charles Haas, who is one of the two experts most frequently cited by EPA itself. Dr. Haas’ analysis showed that MWRA’s ozone treatment plan was more than adequate to bring any risk of illness from pathogens down to levels EPA had used as the basis of the Surface Water Treatment Rule. In contrast, the judge entirely discounted EPA’s risk assessment witness, whom he found not to be a qualified expert in water quality matters.

"No disinfection technology, including DAF/filtration, can offer a 100 percent guaranty of safe drinking water."

Cost effectiveness

Judge Stearns evaluated both views on the cost effectiveness of adding filtration technology to the MWRA’s integrated drinking water strategy as follows:

"Ozonation plus DAF/filtration is a superior technology, offering greater protection against excessive levels of regrowth, [more] capacity of the treatment plant to inactivate Cryptosporidium, and better water aesthetics."

"Because Cryptosporidium is not a current threat to Wachusett water, consideration of the costs and benefits of DAF/filtration is permitted by the amended SDWA."

"It is misleading to present the dollar costs of DAF/filtration in per capita [EPA’s six cents per day], rather than gross terms [$180 million in capital costs]."

"The expenditure of $180 million to achieve less than a 1 percent improvement in the capacity of the MWRA’s treatment plant to inactivate Cryptosporidium is not an efficient or productive use of limited public resources."

"The…reason that it matters whether the nation spends too much to buy a little extra safety is that the resources available to combat health risks are not limitless." [citing Breyer, Breaking the Vicious Circle: Toward Effective Risk Regulation].

"I find credible the testimony of MWRA officials that the added costs of installing filtration treatment will have a substantial financial impact on the MWRA’s program to encourage community pipe replacement and rehabilitation."

"The modular design of the proposed ozonation facility and the completion of a design for a complementary DAF/filtration component will permit the prompt installation of filtration should it become necessary."


Reading between the lines

Judge Stearns specifically noted EPA’s "seven years of constructive collaboration" with MWRA (1990 to early 1997) on a strategy to avoid filtration. This showed that EPA "does not make a habit of mindless enforcement of the SWTR." In response to EPA’s "inflated" concern that this decision could compromise the ability of the United States to enforce the rule in other cases, he commented that he "would not expect to see many more categorical enforcement actions like this one brought on minor and remediable instances of noncompliance" with the SDWA regulations. His overall conclusion on EPA’s case was:

"The case for DAF/filtration of MWRA water, while ably presented, has not been made, either from a cost-benefit perspective, or independently, as a matter of scientific necessity."