The inability of students and others at Virginia Tech in Blacksburg, Va., to make cell phone calls during the April 16 shooting tragedy added to the chaos surrounding the events of the day, students and others have reported in media interviews.

Many students reported being unable to gain access to the wireless phone system either to place a voice call or to send text messages. The reason appeared to be due to a massive increase in wireless call volume, according to carriers serving the Virginia Tech campus.

Verizon Wireless spokesperson John Johnson said that the company began to see traffic climb beyond normal levels after 9 a.m. yesterday. Johnson added that by noon, traffic levels had reached four times normal levels, and stayed that way until shortly after 2 p.m.

"Today what we're seeing is fairly consistently heavy traffic, but nowhere near the levels we saw yesterday," Johnson said.

He compared today's wireless phone traffic to being equivalent to what the company sees during a major football game. "On weekends we see some pretty heavy calling patterns," Johnson said.

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Johnson acknowledged that for awhile during the heaviest call volumes on April 16, some calls did not go through. "We did see some call blocking," Johnson said. "We did also see some heavy text message traffic. A lot of folks have learned that it's much easier to get a text message through at that time than to get a voice call through."

Cingular/AT&T's Mark Siegel said that his company also saw very heavy call volumes, but saw no call blocking. "What typically happens during such a tragedy is that the call volumes go up on the wireless network. We saw that yesterday," he said.

Siegel said that Cingular did not see any service interruptions, although the company did proactively add radios to the cell sites near campus.

Sprint Nextel also reported significantly higher than usual call volumes for its Nextel network in Blacksburg, but declined to discuss whether there were any blocked calls, despite repeated requests.

Spokesperson Sukhi Sahni said that Sprint does not actually provide service to the area, instead relying on affiliates, but does serve Nextel customers directly with its iDEN network. T-Mobile did not respond to requests for information.

Part of the problem, notes Verizon's Johnson, is that wireless companies have to build their networks to handle the demand that they anticipate. "We are engineered to handle heavy call volume there [Blacksburg]. But of course you can't engineer for a tragedy on this scale," he said.

Johnson said that Verizon Wireless has already set up a COLT (cell on light truck) with a microwave backhaul to add more capacity to the Virginia Tech area. He also said that Verizon has offered to staff and equip a calling center or facility at Virginia Tech.

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"This would be some type of location on campus where we'd have staff and about 100 phones for staff, students and faculty to make calls to friends and family," Johnson said.

Siegel said that Cingular/AT&T has offered to provide a COW (cell on wheels) for the Virginia Tech campus, but he said that Virginia Tech officials found that the additional radios the company has already added to its existing cell sites have provided sufficient capacity.

"We had no problems with text messaging," Siegel noted. "It's a great alternative in these situations."

Loss of cell phone service during disasters and other emergencies has been a constant problem, the spokespeople for each company acknowledged.

Experience in past events has shown that wireless networks frequently are unable to sustain the traffic demands placed on them during emergencies.

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