Several streets in Lawrenceville and the Strip District will intermittently close until spring while Peoples Gas lays two new pipelines – one plastic, and one metal – to replace a large-diameter cast iron pipeline from 1887. The project, which begins on Monday, is part of an infrastructure modernization project in collaboration with the City of Pittsburgh to upgrade more than 4,000 miles of pipelines, Peoples said in a statement. The pipeline’s construction will be broken up into sections across several areas to “minimize restrictions at any given time,” according to the company. Work will begin Monday on 32nd Street between Mulberry Way and Smallman Street, and on Mulberry Way between 32nd and 33rd streets. Other streets impacted include:• Mulberry’s intersection from 31stto 38th streets• Smallman Street from 32nd to 38th streets• Stretches on 38th between Mulberry and Foster streets• Charlotte Street between 36th and 38th streets• 36th Street between Charlotte and Smallman• 32nd Street between Smallman and MulberryBy the end of construction, Peoples will have replaced 5,600 feet of pipeline from the 19th century.