Water Main Break
PRE-PLANNING
You don’t necessarily have to be faced with an extrication or fire incident to have an emergency situation on your hands. A rupture in a water main supplying a major urban county brings with it all the catastrophic potential of a fastspreading, multiple-alarm fire.
Cobb County, GA, which adjoins Atlanta on the northwest, found itself in just such a situation about two years ago during the coldest part of winter. Three-hundred forty-nine square miles and 320,000 residents were left without any supply of water. This incident reaffirmed the value of pre-planning and proved once again that, when banding together, the fire service can and often does adapt to and overcome adverse conditions, mitigating the most severe emergency.
At 6 P.M. on December 26, 1983, the national weather service office in Atlanta reported an 80% probability of snow, sleet, or freezing rain within 12 to 24 hours. The fire departments were put on a yellow status (a standby/make ready alert in the event of severe storm conditions) and a check was made of chains for all apparatus, chain boards, batteries, chain saws, hydrant thawing equipment, etc. No city/county-wide alert was issued at this time, but key personnel, which include the city manager, fire, police, public works and water works officials, were notified of the yellow status and told to attend a briefing session at 9 A.M. the next day.
By 8 P.M., snow and freezing rain were covering the ground 80 miles west of Cobb County.
On December 27, public works crews salted streets and bridges, chains were put on the wheels of the fire apparatus, and light fire alarm activity was reported.
By 9:15 A M., the fire, police, and water departments had received a total of about 620 calls for water cutoffs.
At 10 A.M., generally the same weather conditions were reported throughout the state, snowfall had stopped with roughly one inch on the ground and roads were passable with extreme caution. However, Cedartown, Rome, and Summerville, GA, and Birmingham and Anniston, AL, reported severe icing. By 12 noon, most metropolitan Atlanta areas reported severe road conditions and heavy icing, and the Georgia Department of Transportation closed two major highways.
All essential city personnel were retained on duty. Provisions were made to man the city hall switchboard until at least 11 P.M. every day until the storm watch was over.
The Cobb County Water Authority reported reductions in pressures at 6 P.M. and noted that the pressure had been dropping steadily for some time. Marietta has a low and high pressure system due to the various elevations, and the problems were basically confined to the low pressure system, which is at the higher elevation. The high pressure system was holding its own and had adequate water pressure and volume for fire suppression. It was determined, however, that if the problem causing the pressure to drop was not corrected by 8 A.M. the next day, a severe water shortage would exist.
There had been reduced water pressure in this main previously, and a plan had already been formulated to deal with this recurring problem. However, this was the first time that the system was in danger of experiencing a complete shutdown. Therefore, the Cobb County Fire Department, Cobb County Emergency Management, and the Marietta Fire Department reworked their emergency pre-plan and created a task force to address the magnitude of this situation should it develop.
Because of Cobb County’s geographic location and the way the fire department is set up, outside mutual aid is used only occasionally. Within the county, mutual aid among Marietta (the seat of Cobb County), Smyrna, and Lockheed and Dobbins Air Force Bases is practiced on a fairly regular basis. Mutual aid with Douglas County to the south is also common.
Since the problem would involve a lack of water pressure over such a wide area and since neither Marietta nor Cobb County have tankers, tankers would have to be called from outside the normal mutual aid area. Cobb County Assistant Fire Chief H. K. Nixon and Marietta Assistant Fire Chief Philip A. Chovan worked as a team to contact fire departments that use tankers.
Georgia Fire Academy Superintendent Harold Thompson’s office also helped contact tanker departments and compiled a list of what these departments could send. Cobb County Civil Defense Director James Ray rounded up National Guard tankers to transport drinking water for the county’s hospitals, nursing homes, and its 320,000 residents.
In all, 17 tankers, some from as far as 100 miles away, were made available through mutual aid, and Lockheed and the City of Atlanta would send normal engine companies to supplement the tanker task force. The tankers would be stationed throughout the county’s fire stations and would respond to alarms as strike force units. This operation was called Contingency Plan #1. (See map opposite.)
Fire department shift officers and dispatch personnel from Marietta and Cobb County were advised of current road conditions and the water supply problems. Power outages were beginning to severely tax the resources of Georgia Power, Cobb Electric Member Cooperative, and Marietta Board of Lights and Water crews. Fortunately, general fire alarms remained light for all departments involved.
At 1 A.M. on December 28, water charts continued to show pressures dropping. By 5 A.M., the water pressure/supply problem had become critical. By 7 A.M., the problem was noted to be in the Cobb/ Marietta water system, which supplies both the Cobb County system as well as the Marietta city system.
Cobb Water Authority reported a major rupture in the 48-inch supply line feeding a 36-inch water main approximately 80 miles long that loops the entire county. They also reported that the two main gravity tanks on Blackjack Mountain (each containing approximately 5-million gallons of water) and five other tanks (making a total stored capacity of 35-million gallons) were now depleted, some tanks being nearly empty.
By 9 A.M., it was confirmed that the City of Marietta and Cobb County were going to be completely dry in less than an hour at the present usage rate by residents. At 9:30 A.M., the decision was made to activate Contingency Plan # 1. The task force command gathered at the Cobb County Fire Department Headquarters and was operational by 10 A.M. Time and control standards were established, priorities arranged, and assignments made.
It was the duty of the task force to assign, service, feed, house, and establish operational procedures for the mutual aid units. Also, it was determined that the most appropriate method of fire suppression would be to double the intensity of the initial attack. If a fire were allowed to grow and exceed a 1,000 gpm flow requirement, then exposure protection would become the fire defense plan. Therefore, the task force had to acquire and distribute a tanker supply that would approximately double the availability of on-scene water for any initial fire attacks.
Contingency Plan #1
By 10 A.M., requests were placed with all departments involved in Contingency Plan # 1, staging areas were established for incoming equipment to report to and be assigned from, and draft sites were inventoried and established at a lake two miles from the main staging area.
Incoming tankers were topped off with water and refueled prior to deployment to the various fire stations.
Health care facilities, nursing homes, and highly populated areas were the established priorities based on a risk analysis.
By 8 P.M., all incoming units were fueled, filled, and housed. Mutual aid companies were either assigned to a station to run as a team with that station’s fire unit; or assigned a firefighter from Cobb County or Marietta and a portable radio to operate either as a team with one of the county’s engine companies or as a secondary water unit for a firstdue engine/tanker company.
The fire suppression plan proved successful when several fires occurred and, according to plan, were adequately handled by the firstalarm assignments. The largest fire incident during this emergency was at a motorcycle shop. Four engine companies and nine tanker units brought the incident under control in approximately two hours.
Repairs to the ruptured main were completed at 6 A.M. on December 29, 36 hours after the pressure began dropping. Water pressure was returned and conditions improved within a few hours. All mutual aid companies were released by 9 A.M.
A secondary pressure problem occurred at 9:30 A.M. when a new pressure drop was recorded. All available equipment was again placed on standby, but many units were out of radio range. The problem was resolved by early afternoon and the task force returned to their normal operations by noon the next day.
