Montgomery County on Thursday approved the purchase of a $29.97 million public safety radio system, paving the way for the replacement of an existing radio system that dates to 1996 and has recently been plagued by numerous failures and shortcomings.

Commissioner Bruce Castor, who led the committee charged with the task of guiding the replacement process, attributed historic significance to the upgrade.

"This is probably the most significant piece of legislation and the most significant decision the commissioners have made in the five years I've been a commissioner and maybe in the 28 years that I've served in county government," Castor said.

The county's existing system, which was also built by Motorola, suffers from numerous drawbacks that accompany the use of technology associated with cellular telephones. "Dead zones" scattered throughout the county often prevent reliable communication between police, firefighters, and other emergency responders in the field.

John Corcoran, deputy director of external affairs for the county's Public Safety Department, said the dead zones include Canal Street in the Mont Clare section of Upper Providence Township, the Manatawny Street area in West Pottsgrove, the area of Stump and County Line Roads in Montgomery Township, and the La Mott section of Cheltenham, among other areas.

Castor said Lower Merion Township has also suffered from spotty radio coverage with the current system.

Communications inside steel and concrete buildings are also a serious shortcoming, Castor said. He cited examples where two police officers in adjacent hallways within the same building have been unable to hear each other.

About $24 million of the total purchase cost will go towards upgrades to the existing infrastructure, such as the installation of ten additional transmitter towers and the retrofitting of microwave relays to the county's existing towers. The $24 million figure also includes upgrades to about 3,400 radio units owned by the county's various first responder departments.

Another $6.12 million will be used to purchase about 1,800 more radio units.

The county will spend an additional $9.88 million on a 10-year maintenance agreement with Motorola that will go into effect a year after the system has been completed and formally accepted by the county.

The final price tag of the upgrade came in well below the $50 million dollar figure that had been associated with the project in late 2011, towards the end of the last county administration. Estimates for the cost of the project had previously ranged as high as $100 million. Even with the relatively low price, however, the county will need to borrow money to pay for the project. Commissioner Josh Shapiro said the Board of Commissioners, under the guidance of county chief financial officer Uri Monson, would review its borrowing options early in the new year. The $24 million infrastructure cost will likely be borne entirely by the county, though it is possible that individual municipalities will be asked to help pay for the $6 million in new radio units.

"This is a great deal for taxpayers, and a great day for the county's first responders ... this is what happens when government works. Montgomery County is now the example to other counties on how to solve major problems," Shapiro said.

The upgrade is slated to begin "early in 2013," Shapiro said, but neither Shapiro nor other county officials were willing to offer any estimates of how long it would take for the project to be completed.