Earlier today, Pennsylvania American Water today issued a Boil Water Advisory for all customers in its Norristown area water system, which includes 11 municipalities, including portions of Plymouth and Whitemarsh townships (view map). Approximately 33,500 customers may be affected, potentially impacting 86,700 residents.
Montgomery County issued a press release about the situation this afternoon. It included two important pieces of information.
The first is that while it is in the process of being repaired, there is not currently a timetable for how long repairs will take.
The second is that the boil water advisory will remain in place until repairs have been made, pressure has been restored, and there have been two consecutive days of negative sampling for total coliform bacteria with compliant chlorine residuals.
So expect this to last at least two-to-three days.