More than a decade ago, if one had asked an economist to estimate the impact of the closing of Lucent Technologies' Merrimack Valley Works plant, the answer would have been "devastation."

That grim prospect has now come to pass, as Lucent has pulled the last of its workers from the once thriving facility, a mammoth manufacturing plant in North Andover that was once the company's largest worldwide.

The result has not been devastation, but neither has it been good for the region nor for the town. And now that plans to build a large housing development adjacent to the plant have fallen by the wayside, North Andover will have to seek its economic salvation elsewhere.

The Valley Works, which made the networking equipment that powered the world's telephone systems, once employed more than 10,000 people. Workers, many of whom remained with the company from high school graduation through retirement, still called the plant "Western Electric" after its origin as an electric coil-winding company in Haverhill.

In 1991, the Merrimack Valley Planning Commission did a study that concluded that every job at the Valley Works was responsible for another 1.5 jobs in the community at companies that provided services and materiel to the plant. Workers spent their better-than-average paychecks in the community as well.

The impact of the closing as been lessened, because it was a slow, steady decline, rather than a sudden death. That's what has given the community time to adjust. Still, in the middle of a recession, the loss hurts, as much from its symbolism as from the actual economic impact.

The owner of the plant and property, Orit Goldstein, has been filling the space vacated by Lucent with small manufacturing operations and other businesses. But her plan for 530 rental apartments on the 32 acres adjacent to the plant is on hold, because the developer, Avalon Properties, has pulled out of the project.

It's likely that any development of housing at the site will have to wait for an upturn in the economy and the end of the credit crisis.

North Andover officials had been hoping the new tax revenue and incentive payments from the development would ease the town's annual budget crunch. For a while, at least, the town will have to make do with less.