Regional officials on Wednesday launched an investigation into how a June 29 storm was able to knock out 911 emergency phone lines across Northern Virginia, saying the region couldn't keep losing emergency communications to bad weather.

The Metropolitan Washington Council of Governments set aside a $50,000 budget to study the 911 failure, the third such collapse in as many years.

Residents who called 911 in Fairfax, Arlington and Prince William counties couldn't get through at times, even days after the storm and after the call centers were supposed to be back online. In some cases, calls were routed to the wrong jurisdictions.

Officials blamed Verizon, which provides phone service to the local 911 call centers, for lacking adequate backup power after hurricane-force winds knocked down power lines across much of the region.

"The elected leadership in our region expect better," said Frank Principi, chairman of the Council of Governments and a Prince William County supervisor.

The Verizon hub in Arlington that handles much of Northern Virginia's emergency communications switched to battery power after the storm knocked out the electricity, said Steve Souder, Fairfax's director of public safety communications. But the batteries failed after eight hours, and the system didn't switch to a generator as expected, he said.

"[911] absolutely must be flawless," Souder said. "The hub must be more robust, must be monitored more closely. ... You can't wait eight hours and have it fail."

Northern Virginia officials said they were frustrated that Verizon continues to have problems since the 911 system went down during the 2010 and 2011 snow emergencies.

"It seems that whenever there is a catastrophic weather event, we're all struggling with something," Fairfax County Board of Supervisors Chairwoman Sharon Bulova said.

Kyle Malady, vice president of network and technology for Verizon, promised to work with local governments to determine what went wrong.

"When we sustain an outage as serious as this, you can be sure we're going to take every action we can to get to the bottom of it," he said.

The Virginia State Corporation Commission and the Federal Communications Commission are also launching investigations.