TAUNTON, Mass. (AP) – With another storm bearing down, crews began working Friday to build a new rock dam across the Mill River just downstream from a decrepit wooden dam that threatened to break and flood the city’s downtown.

The work began four days after the Whittenton Pond Dam buckled and starting breaking apart, prompting city officials to evacuate downtown Taunton, and seven years after state inspectors warned that some of the old dam’s wooden supports were rotting and needed replacement.

Work on the permanent new dam of massive boulders and crushed rock was expected to continue into the night on Friday. The old dam was to be dismantled and detonated today, ahead of the foul weather forecast to arrive tonight.

Fire Chief Joseph Rose said officials scrapped plans to reinforce the existing dam after examining the structure and finding “it’s not really fixable.”

“The rock dam provides a whole degree of permanence and stability that is not available in the wood structure,” he said.

Taunton has received more than 11 inches of rain this month, including 7 inches last weekend alone. Mayor Robert G. Nunes declared a state of emergency on Monday and ordered about 2,000 residents to evacuate after the 173-year-old dam threatened to collapse.

Residents and businesses were finally allowed back in on Thursday night and Friday morning after millions of gallons of water were pumped from Lake Sabbatia, above the dam, and piped back into the river farther downstream.

Lowering the water level by more than 3 feet relieved the pressure on the dam enough to allow engineers to examine the wooden structure and see it was too badly damaged to save, Rose said.

In March 1998, an engineering firm hired by the state Office of Dam Safety inspected the dam and recommended a series of fixes. “The condition of the timber supports vary from relatively new to rotted and severely deteriorated,” reads the report prepared by Pare Engineering Corp. “Some of the vertical supports near the right abutment were observed to be severely rotted.”

The inspectors recommended replacing missing and deteriorated logs, clearing the downstream channel of debris, replacing a missing buttress and bolstering a security fence. It estimated the cost of the repairs at $53,000 to $100,000.

“If the ongoing maintenance is not continued and the structure is allowed to deteriorate further, unsafe conditions could develop,” the report said.

State officials and the dam’s new owner have said some repairs were made, but it’s unclear if all the fixes recommended in 1998 were made.

Asked Friday about the 1998 report, Rose said he was focused on getting the new dam built.

The report also cautioned that an emergency evacuation plan for residents and businesses downstream should to be drawn up in case the structure ever failed.

The dam owner at the time of the report was identified as L & O Realty Trust of Taunton, which does not have a current phone listing.

Jefferson Development, of Leominster, which acquired the dam two years ago, has said repairs were to have begun last Friday but were delayed by the heavy rains.

More bad weather is on the way, with 1 to 3 inches of rain expected this weekend and meteorologists keeping a close eye on Hurricane Wilma, which stalled Friday near Mexico’s Yucatan Peninsula, but could still skim the East Coast of the U.S. sometime next week.

With the new dam, Rose said, “Whatever comes … we’ll be able to deal with.”

He cautioned that the threat had not entirely passed for the working-class city south of Boston. A state of emergency will remain in effect until early next week.

“We still have the danger we had before,” Rose said. “Now we’re trying to fix it.”

Truckloads of three-ton boulders began arriving Friday afternoon and crews used an excavator to move them into position about ten feet in front of the existing dam. The dam will span the river, which is about 100 feet across, and be 8- to 12-feet thick, officials said.

A half-mile away, in the downtown business district, shop owners were welcoming customers back for the first time since evacuating. Anthony Lentine estimated his deli lost about $1,000 for each of the three days he was closed, but he didn’t blame town officials for not taking chances.

“After seeing what happened in New Orleans,” he said, “God forbid we wouldn’t want anything like that to happen here.”

AP-ES-10-21-05 1854EDT