Cost of cleaner water: $40m

Upgrading the Pierce Island sewer plant to comply with a recent federal ruling will probably cost ratepayers about $40 million, but not anytime soon, Portsmouth, N.H., officials said last week.

The US Environmental Protection Agency sent a letter to the city last month saying it would not renew a longstanding waiver that had allowed the plant to operate outside Clean Water Act standards. Making the necessary improvements would mean several years' worth of scheduling, negotiations, design, and engineering before construction starts or rates go up, said City Manager John Bohenko.

''It's going to be very, very expensive," he said. ''Any increase in the footprint of the plant needs to be carefully considered. What we need to do is work with the EPA over the next several moths to come up with a time frame and schedule. . . . We need to look at all options."

The Pierce Island plant, which is a primary treatment facility, dumps 4.5 million gallons of partially treated wastewater into the mouth of the Piscataqua River each day. The EPA has said that it will require the plant to add another level of cleansing, called secondary treatment, as required under the Clean Water Act, which would lead to a 25 percent cleaner discharge into the river.

Options for meeting the EPA's demands include diverting some of the waste water now treated at Pierce Island to one of the city's other treatment facilities. Another option is building a new plant on the mainland and dismantling the Pierce Island plant altogether.

Adding a secondary treatment process to the existing plant would make for a bigger, more noticeable facility on what is still a scenic recreation destination on the Piscataqua River.

''You have to remember we want to do it right and not quickly, especially with that location," Bohenko said. ''Whatever we do, we're going to be living with it for 50 to 100 years."

The plant was built well before the Clean Water Act was passed in 1977. It was originally issued a permit to operate as a primary treatment facility under that act in 1983. Over the next few years, improvements to the plant kept pace with new restrictions added to the federal legislation.

In 1990, the plant's permit was denied because it provided only primary treatment, but it was granted a waiver to continue operations in light of the city's continued efforts to improve sewer services citywide, EPA and Portsmouth officials said. Now the EPA says it is time that waiver was ended, a move that the New Hampshire Conservation Law Foundation has demanded for more than a year.

A lawyer with the environmental watchdog group, Tom Irwin, said that he sympathizes with city ratepayers but that the upgrade is long overdue. Pierce Island is pumping dirty water into an already stressed tidal river that washes into both the Gulf of Maine and the Great Bay, he said.

''The bottom line is this is a major discharger into a critically important river," Irwin said. ''This plant is the largest discharger of wastewater on the New Hampshire seacoast. We ought to have truly protective treatment measures in place here, and the plant as it presently operates doesn't have that."

The EPA agrees. In an April 13 letter, the agency said it is denying the waiver and drafting a notice recommending that the Pierce Island plant be permitted for secondary treatment only. When that draft permit is issued, probably early this summer, it will trigger studies and paperwork, according to EPA and city officials.

There will be a 60-day public comment period once the draft permit is received and before a final permit is issued. Those comments could easily delay the process more, said an EPA environmental engineer, Roger Janson. He expressed doubt, however, that the outcome would be substantially changed.

''Obviously, the fact that we intend to put out a draft permit with secondary treatment requirements indicates we think that's the appropriate direction to go in," he said.

One of the details that will be ironed out with EPA after the new permit is issued is how quickly the city must comply. The city wants to prepare a waste-water master plan that will fold the Pierce Island plant resolution into an ongoing $25 million sewer improvement program initiated eight years ago.

The long-term project aims to replace the antiquated sewer pipes that connect to storm drains downtown and often get overwhelmed during heavy rain, flooding businesses and homes with untreated wastewater. The city considers this problem more pressing than the upgrades to Pierce Island, Bohenko said.

In 1990, the city spent $12 million for improvements to the primary-treatment facility, more than doubling the amount of waste it was able to remove from the water. The step up to secondary treatment would mean an improvement of approximately 25 percent.

''The most immediate impact on the environment was this issue of separating our storm water from our sewage," Bohenko said. ''That problem is a crucial issue. We were having backups into people's basements because of storms and tides, and we've eliminated a huge amount of that."

Fortunately for ratepayers, that project is already financed through state loans, Bohenko said. Complying with the latest EPA recommendations is not, and the work must eventually be paid for by ratepayers, he said.

Meeting the EPA order would cost at least four times the city's annual $10 million sewer budget, but it would be financed by a bond issue and repaid over several years to ease the burden on ratepayers, the city manager said. The final cost is still unknown, he added.

''We always knew we'd have to go to secondary treatment" at Pierce Island, Bohenko said.

''We just hope that we can phase it in over many years. We have to show how we are going to fit all this in and take appropriate steps to get what's best for the city. That's the important part."