Wireless systems brace for storms
GCN Insider: Carriers harden networks on coasts as hurricane season arrives
- By William Jackson
- May 22, 2008
WITH THE HURRICANE season opening June 1 predicted to be more active than usual, major wireless carriers have been hardening networks in the vulnerable Southeast and Gulf Coast states.
Florida has been the focus of a lot of this activity because of its double-coast exposure to the Atlantic Ocean and Gulf of Mexico.
Verizon Wireless has spent $150 million in the state during the past year ' and Sprint Nextel has spent $59 million ' to add cell sites, generators and fuel storage facilities; position mobile emergency response equipment; and strengthen key switching facilities.
'Florida is generally an area that seems to get hit hardest by storms,' said Sprint spokeswoman Stephanie Walsh.
The past year's effort is not a onetime expenditure but part of an ongoing investment to ensure that wireless communications remain in operation during an emergency or can be quickly restored if there is a disruption.
Mobile equipment can temporarily enhance network capacity in disaster areas, providing additional cellular sites or satellite links to accommodate emergency response teams arriving in stricken communities. Hardened networks would benefit first responders and other crews responding to an emergency.
According to forecasts by Philip Klotzbach and William Gray of Colorado State University's Department of Atmospheric Science, this year's six-month Atlantic hurricane season is likely to produce an above-average number of storms.
Although the past two seasons have not been particularly harsh, 'we foresee a well-above-average Atlantic basin tropical-cyclone season in 2008,' they wrote. 'We anticipate an above-average probability of a United States major hurricane landfall.' In a forecast updated in April, they predicted eight hurricanes this year with four described as intense.
The most common threat to communications during a severe storm is not destruction of physical infrastructure but loss of power. Individual cell sites tend to survive high winds and flooding, Walsh said.
'That is a testament to the site planning' for the towers, she said. 'That's why we focus on backup power.'
All major switching sites and points of presence linking networks to other networks have backup generators. Sprint has added more than 1,300 generators in the past year in the Southeast and Gulf Coast states, 1,000 of them in Florida. At some cell sites, battery power is also used to maintain operations during an outage. Key geographic areas targeted for enhanced backup include:
- High call-volume sites and sites covering evacuation routes.
- Public safety organizations, state and local emergency operation centers, military bases, and other government facilities.
- Hospitals and nursing homes.
- Major commercial airports and ports.
Verizon Wireless spent $20 million to enhance its Tampa Bay switching facility, doubling its traffic capacity and adding backup power. The facility is designed as a regional emergency operations center able to withstand a Category 5 hurricane.
The company also erected about 100 new digital cell sites in the past year, about 85 percent of them with on-site generators and expanded fuel tanks.
'Our expectation is that backup will last long enough to get power back up,' Walsh said. 'Most outages are of a relatively short duration.' But there are times when outages can outlast generators' reserve batteries or fuel supplies, and service then depends on getting more fuel into the stricken areas. If roads are not passable, service could be lost during an extended outage.
When service is impaired or call volumes are unusually high in the wake of a disaster, there also is a federal program to give priority service to qualified first responders.
Callers participating in the program can use a code that puts them at the front of the queue for cellular access.
The program does not block or drop other calls, but it gives priority users a better chance of completing their calls on a congested network.