PaperWorks Industries Inc. will layoff 147 when it shutters operations in one of the nation's oldest papermaking plants, the PaperWorks Philadelphia Mill on Flat Rock Road in Manayunk.

According to the Worker Adjustment and Retraining Notification, or WARN notice, filed with Pennsylvania's Department of Labor and Industry, the plant is expected to close on April 14.

The company's website describes the plant as the world's largest in the 1860s, and said it continues to be an industry leader, "currently operating the widest paper machine in the world."

Founded in 2008, PaperWorks Industries, a paperboard manufacturing company, is headquartered in Bala Cynwyd, employs 2,000 and processes 400,000 tons of 100 percent recycled paperboard annually in plants around the nation and in Canada, its website said.