A large watermain break is affecting residents in the South Hills.
Pennsylvania American Water says crews began working at 10 a.m.
The 12-inch watermain break is on Washington Pike in Bridgeville and is affecting that community, along with Scott Township and Upper St. Clair.
Some businesses in the area had to close down.
Crews expect to work until around 5 p.m. Tuesday on the repairs.
PA American Water says once that water service is restored that people may see discolored water.
If it is discolored, run your cold tap on the lowest level of the house for three to five minutes until clear.
Those impacted can sign up for alerts here.