About two years after Forbes Dewey Jr. and his wife, Carolyn, purchased their home in the North End, they were hit with a condominium-owner's nightmare: wooden pilings holding up the foundation had begun to rot and would require more than $2 million in repairs to keep the building from sinking into the landfill it was built on more than a century ago.
Hundreds of historic buildings in the Back Bay, South End, and other parts of the city's core are in similar straits -- their foundations threatened as ground water recedes, exposing pilings to air and bacteria.
To Dewey's surprise, however, the North End and several other neighborhoods were omitted from a target area where the city plans to require most renovation work to be done in a way that will replenish ground water instead of further depleting it. The designation of a ''Groundwater Conservation Overlay District" is scheduled for a vote by the Boston Zoning Commission on Wednesday.
''It was recognized by a lot of people that the Back Bay and the Fenway weren't the only places" with ground-water troubles, Dewey said. ''If we are going to have an overlay district, we should have it in all the city neighborhoods that are at risk," he said last week, as he and others concerned about ground water scrambled to mount a last-ditch effort to extend the district's boundaries.
Dewey said he believed the North End's inclusion in the district was ''a done deal" until about two weeks ago, when the Boston Redevelopment Authority's board approved a revised plan that excluded the North End and East Boston neighborhoods, where at least two cases of piling rot have been confirmed.
The BRA also opted to hold off on including Fort Point Channel and the Charlestown waterfront, where similar problems are feared. The Leather District and the Bay State Road areas, however, were added to the district map before the BRA vote as a result of public comments about problems in those areas, according to a BRA official.
City officials said they are sympathetic to the plight of property owners facing costly repairs, but said more information is needed to determine where ground-water problems are severe enough to warrant inclusion in the new district.
''We want to make an informed decision before we subject property owners to a decision that could cost them time and money," said James W. Hunt III, chief of the city's Environmental & Energy Services.
Elliott Laffer, executive director of the Boston Groundwater Trust, a city-funded group that monitors the ground-water levels in several neighborhoods, said his organization began expanding its well network to include the North End, Eastie, the Bulfinch Triangle, and a few other city districts last year and should have data on water levels later this year.
So far, Laffer said about 20 wells in the low-laying parts of the North End, where land ''was made" to expand the natural shoreline, indicate ground water there is not dangerously low. In East Boston, the trust dug its first 14 wells last fall and will bring the total to about 100 wells by springtime, he said.
In Eastie, ''we don't have enough to tell us much," Laffer said. ''We do have a couple of wells with readings that are concerning. We'll have much better data in the spring."
Underground basements, garages, and tunnels tend to block the flow of water, while common construction practices divert rainwater from buildings and pavement into sewers, further depleting underground water levels, according to experts.
The new district, which encompasses the Back Bay, South End, the Fenway, Chinatown, the flat of Beacon Hill, and a few other areas in the city's inner core, will face construction rules designed to reduce ground-water runoff. Developers, and any homeowner planning either an addition or extensive renovation, will have to invest in dry wells and special paving materials that ''recharge" underground water by recycling rainwater. To streamline the paperwork and reduce the costs involved, Hunt said the city plans to hire an engineering firm to develop standard dry well specifications that would be available to anyone planning a construction project within the new district.
All of this is part of the city's larger strategy to stem the flow of ground water away from pilings holding up hundreds of historic buildings. Creation of the overlay district is an important part of the plan, but the new construction rules are no silver bullet solution, since finding and plugging leaky tunnels and other infrastructure will provide a bigger boost to areas where ground water is dangerously low, Hunt said.
''If your property's pilings are rotted, this isn't necessarily the solution" either, Hunt said. Nevertheless, he and other officials held out hope of expanding the overlay district once they have a better understanding of the problems around the city. Before making a decision, Hunt said, officials would meet with neighborhood residents and try to reach consensus.
Boston City Councilor Paul Scapicchio echoed the view that more data is needed for residents to decide if they want to become part of the overlay district. Scapicchio raised eyebrows and the ire of ground-water activists last month when he urged the BRA board to exclude the Eastie and the North End neighborhoods he represents from the overlay district until the problems are further studied.
''I am supportive of ground-water remediation but that we have to do it properly," he said.
Activists and homeowners, however, expressed skepticism.
''We'll sink into the ocean while they are studying it," said Robert Skole, who lives at Lincoln Wharf on Commercial Street, next to Battery Wharf, where construction workers this winter are building a new hotel and marina plus luxury condos and an underground parking garage.
The Battery Wharf project would have had grandfather status and been exempt from the new rules even if the North End was included in the new overlay district.
Nevertheless, Skole, who says his 1901 building sits on ''10,000 pilings," would like the protections to govern future building in the area.
''We don't need any more studies," said Joan Lancourt, a Back Bay resident and member of the Citywide Groundwater Emergency Taskforce formed two years ago. While Lancourt's neighborhood is part of the proposed new district, citywide activists plan to attend Wednesday's Zoning Commission hearing to voice opposition to excluding the other neighborhoods.
''We know that any place built on landfill, where the buildings were built on pilings, is at risk. Our goal is prevention so we don't continue to remediate problems," she said.
''How many more $50,000 to $100,000 assessments do there have to be before the city takes action?" asked Lancourt, referring to the Deweys' Fulton Street building, where repair work costs set for completion this spring were split among the building's 23 condo owners.
''It's been very painful. We certainly would like to help our neighbors avoid the same problem," said Dewey, who is skeptical of the city's pledge to revisit the subject once more data is available.
''That's just a simple way of saying 'you're not going to get it,' " Dewey said of the promise to expand the district as necessary. ''It will be almost impossible to get this back on the agenda."
Christine MacDonald can be reached at email@example.com.