File photo Employees of Pennichuck's corporate headquarters have moved into its new location at 25 Walnut St., the former Nashua District Courthouse building, which underwent extensive renovations, including an addition, over the past year.

NASHUA – Pennichuck Water Works officials announced in a mass mailing and on its Website that roughly 60-70 employees have moved into the corporation’s newly renovated and expanded headquarters at 25 Walnut St.

Located most recently at 4 Water St., the office building just off Main Street on the southern shore of the Nashua River, Pennichuck’s corporate headquarters was at 25 Manchester St. in Merrimack for a number of years.

But although employees are now working out of the new headquarters, the building remains closed to the public due to the COVID-19 pandemic. Officials said residents will receive a notice when the offices reopen.

They also ask that all mail is sent to Pennichuck Water, P.O. Box 428, Nashua, 03061-0428.

Its customer service phone number remains the same – 882-5191 locally or 800-553-5191.

For the vast majority of Pennichuck’s nearly 170 years serving as Greater Nashua’s water utility, its headquarters was at 11 High St., in a roughly 120-year-old brick building that’s now part of the Bank of America building at 157 Main St.

It wasn’t long after the city purchased Pennichuck for $138 million, in a landmark transaction finalized in 2012, that the firm’s desire to return its headquarters to downtown Nashua began generating discussion.

Officials began eyeing the former Nashua District Courthouse, a roughly 40-year-old building that sat empty since the district court moved to the first floor of the Superior Court on Spring Street.

City and Pennichuck officials came to agreement and staged a symbolic groundbreaking ceremony in October 2019, and construction began shortly thereafter.

Dean Shalhoup may be reached at 594-1256 or dshalhoup@nashuatelegraph.com.