CenturyLink faces beefed-up reporting requirements for its Minnesota 911 contract after a state report found the company did not adequately respond to a major outage last August, which led to almost 700 dropped emergency calls.

"There was a gigantic failure by CenturyLink and its vendor," Katie Sieben, chairwoman of the Minnesota Public Utilities Commission (PUC), said at a commission meeting Thursday.

CenturyLink administers the state's 911 system, which went down for 65 minutes on Aug. 1. The outage was caused by human error at one of CenturyLink's vendors, but a state investigation faulted CenturyLink, too, for communication shortfalls.

Most emergency call centers did not know of the 911 breakdown until it was over, while the Minnesota Department of Public Safety wasn't adequately informed by CenturyLink either, concluded an investigation by the state departments of public safety and commerce.

The PUC voted 5-0 Thursday to require CenturyLink to meet with the public-safety department and submit six monthly reports, which will among other things explain how the 911 system has been improved. CenturyLink also will have to report the circumstances and reasons for failed 911 calls during the previous month.

And CenturyLink must meet with the public-safety department and establish procedures to improve communications about outages to the state and to 911 call centers.

CenturyLink generally agreed with the recommendations before the PUC, though there was some debate between the company and state agencies about the scope of the reporting requirements.

"If the commission's role for us is to work with the [public- safety department], we are fully comfortable with that," Jason Topp, a CenturyLink attorney, told the PUC. "We are on the phone with them constantly."

Monroe, La.-based CenturyLink, Minnesota's largest landline carrier, is in the third year of a five-year $29 million contract to administer the state's 911 system. CenturyLink in turn has a contract with Colorado-based West Safety Services to help fulfill its 911 obligations.

On Aug. 1, a West technician made a mistake while doing maintenance, disrupting service at one of West's two "emergency communications management centers." The redundancy of the system partly failed: While 356 calls to 911 were successfully routed through West to emergency call centers in Minnesota, 693 calls were dropped.

It appears to be the most extensive breakdown of Minnesota's 911 system in about 30 years.

The PUC ordered an investigation three weeks after the outage. The inquiry, conducted by the commerce and public safety departments, found that neither public safety nor CenturyLink knew of the maintenance work at West because it was "erroneously considered to be routine."

The report said that no automatic alarms about the outage were sent to Minnesota's emergency call centers, which weren't formally notified of the dropped 911 calls until a few minutes after the system was fixed. CenturyLink also had an "unacceptable and unnecessary delay" in providing information about the outage to the public-safety department.

"There were multiple levels of failure," Dan Craigie, deputy director of emergency communications at the state's public safety department, told the PUC Thursday.

In reports to the PUC last winter, CenturyLink said West has made software improvements to prevent the type of error that led to August's outage. West has also improved the alarm system for 911 calls that don't go through, CenturyLink reported.

CenturyLink said last week it "places a high priority on public safety" and has taken several steps to address problems outlined by the state.