Just before 10 a.m., Mark Stewart of the Washington emergency operations center told a local news channel that though service had been fully restored, "sporadic call routing difficulties may still occur."
There have been no reports of emergencies where people could not receive help because of the outages, according to Washington state Emergency Management Division spokeswoman Wendy Freitag.
The problem was first identified around 1:30 a.m. in Sheridan, Ore.
Officials have not yet identified the cause of the outages, which sometimes made all phone lines unavailable, and at other times left just one or two lines open. During this period, residents were advised to use a cellphone to contact 911 because cellphones reportedly worked better to call 911 than landlines. Residents were also advised to visit a fire station if 911 was not working.
CenturyLink serves all the 911 dispatch centers in the region, which are all linked together, but the company reported that the outages in Washington and Oregon were not connected.
In Washington state, the Emergency Management Division and the King County Office of Emergency Management will launch investigations into what caused the outages, which will include talking to CenturyLink to ensure that such outages do not occur again.
