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Weather conditions in 1994 were perfect for disastrous Alberto

Flooding from Alberto covered an area as big as Massachusetts and Rhode Island combined

NOAA rain accumulations from Tropical Storm Alberto. (National Hurricane Center graphic)

NOAA rain accumulations from Tropical Storm Alberto. (National Hurricane Center graphic)

ALBANY — On the western coast of Africa, an unremarkable tropical wave was detected on June 18, 1994, in Dakar, Senegal, through rawinsonde data. It moved westward and crossed the Atlantic Ocean, where it brought thunderstorms to the Virgin Islands. As it neared the Bahamas a couple of days later, the storm activity subsided.

Go here to see the 20th anniversary special section on the Flood of 1994.

On June 29, the wave had reached Cuba, where its thunderstorm activity intensified again. That’s also when weather watchers with the National Hurricane Center of the National Oceanic and Atmospheric Administration noticed a weak circulation in the storm. A reconnaissance aircraft was dispatched to gather information.

Experts with the Hurricane Center looked at the data and made it official. It was June 30 and the first tropical depression of the 1994 Atlantic hurricane season had formed as a poorly organized system over Cuba’s west coast. Continuing to move west, the depression got better organized after leaving the island. It gained strength and turned northwest to the Gulf of Mexico.

On July 2 at 0:00 UTC time (8 p.m. July 1), it became the first named system of the 1994 hurricane season.

Tropical Storm Alberto.

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Tropical Storm Alberto’s storm path in 1994. (National Hurricane Center graphic)

As it tracked north toward the Florida panhandle, Alberto intensified. Just as it made landfall near Destin, Fla., about 11 a.m. July 3, it was packing winds of up to 65 mph. By 8 p.m., it had been downgraded to a depression as it met a cold front from the northwest around Columbus, creating warm, moist air and instability. Moving lazily, what was left of Alberto took two days to travel to a point near Atlanta, its drenching rainfall already sending rivers past their flood stages. It stalled. Then, it moved slowly on a westerly and southerly path to Alabama, crossing over part of the path it took going north.

On the evening of July 7, the remnants of Alberto dissipated over central Alabama.

THE FLOODING

Alberto’s effects, however, were just starting to be felt. By that time, 25 of the 31 people in Georgia who would die as a result of its torrential rains on already saturated soil had lost their lives. Flash-flooding hit Sumter County especially hard as earthen farm dams were breached. Cities and communities along creeks and rivers — including Albany, Newton, Baconton and Montezuma — were about to experience record flooding. A quarter of Dougherty County’s population would be displaced as the Flint River literally split Albany in half, rendering the four bridges that connected the two segments of the city impassable.

Initially seen as a 100-year flood, it came to be seen as the kind of flooding that is only expected to hit an area once in a 500-year period.

The heaviest rainfall was in the Americus area, which received a record 27.61 inches of rain July 3-9. An incredible 21.1 inches of that rainfall came within a 24-hour period July 5-6. The National Weather Service’s Climate Analysis Center determined that the heaviest rainfall — 16 inches or more — fell in a narrow band across Southwest Georgia and Southeast Alabama. Over a much broader area, however, locations experienced at least 8 inches of rain, creating what NOAA officials described as “tremendous runoff” that resulted in the widespread flooding.

Just how widespread was put in perspective in an Oct. 12, 1994 National Climatic Data Center technical report by meteorologist Tom Ross and physical scientist Neal Lott. “In Georgia alone,” they said, “the flood waters covered an area the size of Massachusetts and Rhode Island combined.”

With Massachusetts at 10,555 square miles and Rhode Island at 1,212 square miles, that means that at least 11,767 square miles — about 19.8 percent — of Georgia’s 59,425-square-mile area was underwater.

A SWELLING FLINT

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Waters flow over the Georgia Power dam in north Albany. The Flint River, swollen by rain, heavy runoff and flooding tributaries upstream, quickly rose to a historic height of 43 feet in Albany on July 11, 1994. (Albany Herald file photo)

Of the 30 locations that experienced new record flooding from the massive volume of water, 20 were on the banks of the Flint River. Twenty-three locations saw flooding greater than what a location would expect to occur once a century, with 18 of those locations beside the Flint.

The Ocmulgee River crested July 7 at Macon, setting a new record level of 35.4 feet, 5.5 feet higher than the March 1990 record. The Kinchafoonee Creek gauge near Dawson reached a record 26.56, 13.56 feet above flood stage and breaking its 4-year-old record by more than 4 feet.

The next day, the Flint crested at 35 feet at Montezuma (15 feet above flood stage), breaking a 65-year-old record of 27.4 feet.

On July 11, the Flint swelled to a record 43 feet, more than double the 20-foot flood stage, in Albany, breaking a 69-year-old record of 37.8 feet.

The highest water, however, was downstream at Newton. On July 13, the Flint swelled to a record 45.25 feet, swamping the old downtown business area. The river has a flood stage of 24 feet at that location. The previous record, set right after Albany’s old record in late January 1925, had been 41.3 feet.

And while it sustained severe flooding, the only community that got any kind of a break from the forecasts was Bainbridge. Emergency management personnel there had evacuated an area that would have been affected had the Port City experienced the 45-foot crest that was predicted to hit on July 13. The water crested at 37.3 feet, below that city’s record of 40.9 feet that also was set in January 1925.

An interesting note is how the flood forecasts quickly worsened. On the morning of July 5, forecasters expected the Flint to crest in Albany at a maximum of 31 feet on July 11. By mid-afternoon on the 5th, the forecast was bumped up to 37 feet. The next day, the cresting was moved up to the 9th with a new maximum near 44 feet. By shortly after noon June 10, a maximum 46-foot crest was expected the next day, with the crest coming in 3 feet below that.

The story was similar in Newton, where the river forecasters on July 5 projected a maximum 32-foot crest on the 13th. That was changed to a 38-foot crest on the 12th that afternoon, and projections by July 7 were for 45 feet with the river expected to top out by the 11th. On the 10th, that was revised to as much as 46 feet on the 12th. The crest hit 9 inches below that projection about 6 a.m. July 13.

FAST-MOVING WATER

The volume of the water that moved toward the Gulf was astounding. Albany’s crest discharge was estimated at 120,000-125,000 cubic feet per second. In Newton, it was 94,400 cubic feet per second.

A National Weather Service summary of the disaster stated: “Some of the most spectacular flooding occurred along the Flint River. The crest, generally 20-25 feet above flood stage and 4-6 feet above the previous record crest (January 1925), wreaked havoc as it moved downstream and caused immense damage as well as the evacuation of tens of thousands of people. Blackshear Dam, upstream of Albany, was overwhelmed; and the high pool level forced the evacuation of residents in about 1,400 homes around the lake (almost all of which were ultimately inundated) before the dam was overtopped and breached.

“Albany suffered major flood damage after nearly one-third of its 76,000 residents were evacuated. Farther downstream, at Newton, nearly the entire town was flooded to depths of 15-20 feet. After exceeding previous record flood levels as far downstream as Newton, the Flint River at Bainbridge crested about 4 feet below record levels (although the measured discharge of 108,000 cfs [cubic feet per second] exceeded the previous record discharge of 101,000 cfs). …”

More than 400,000 acres of Georgia farmland were flooded, a National Climatic Data Center technical report said, with at least 60,000 acres of peanuts, 19,000 acres of cotton and 10,000 acres of corn submerged. Another 400,000 acres in Alabama were also swamped or damaged, the report said.

According to a report by the Centers for Disease Control & Prevention, 175 roadways in 30 counties were closed at some time during the flood, and more than 100 dams and recreational watersheds were breached or destroyed. Of the deaths in Sumter County, half were attributed to the failure of 7-9 earthen dams that inundated Creeks. The Department of Natural Resources said the number of breached dams totaled 218 with 35 of those in Sumter.

ASSESSING THE DISASTER

In assessing the disaster, National Weather Service officials arrived at some conclusions that have affected later events, including the flood of 1998. They concluded that more needed to be done to inform people about the dangers of floods and preparing for them, saying NWS policy should require periodic — preferably annual — visits with state and local-level emergency officials and other “action agencies” to review flood threats, particularly the danger to those in vehicles.

They also discovered during the post-disaster interviews that interest in the storm system dissipated much more quickly than the storm itself did. “The public’s perceived threat from Alberto appeared to lessen once it made landfall,” the summary said, noting that several of the individuals interviewed remarked that the storm’s landfall was overemphasized while not enough attention was placed on the heavy rain and flooding that followed inland. The conclusion was that it was probably more of a media and public perception problem than a forecast issue, since meteorologists warned on July 4 of the “very dangerous flash flood and flood situation” for Georgia that day and overnight.

“The NWS and NOAA should take maximum advantage of the recommendations from the 1995 Interdepartmental Hurricane and the NOAA Hurricane Conferences, which focused on the inland effects of tropical cyclones, in order to enhance the public’s perception of the dangers associated with landfalling tropical cyclones,” the recommendation said. “In addition, the WCMs (warning coordinating meteorologists) in all areas which might be affected by the aftermath of decaying tropical cyclones should re-enforce the potential for severe flooding from such storms with the user community.”

The high death count — 31 in Georgia and two in Alabama — also weighed heavily with the survey team, which said there was a possibility the public in general had been inadequately educated about the dangers and locations of flood-prone areas — particularly roads — and the location of safe evacuation routes.

“If funding permits, the NWS, in conjunction with FEMA and appropriate state and local agencies, should embark upon a campaign to educate the public as to their local flood-prone areas,” the NWS disaster team concluded. “This should include a widely distributed array of visual representations of flood-prone areas depicting roads and bridges as well as portions of communities that may be potentially inundated by floods. Additionally, the NWS should plan to issue graphical flood forecasts as well as the traditional text products.”

LESSONS LEARNED?

Still, not everyone is likely to heed warnings. In April, Georgia, Florida and Tennessee residents were polled for a AAA Consumer Pulse Survey that found almost nine out of every 10 Georgians — 89 percent — would evacuate if warned of danger. But for 70 percent of the Georgia respondents, the survey, which had a margin of error of 4.9 percent, said it would take at least a category 2 hurricane (minimum sustained wind speed of 96 mph) to prompt them to leave their homes.

Alberto’s winds never reached hurricane force.

In addition, the survey found that only 36 percent of Georgia respondents make preparations for hurricane season or other severe weather conditions. That lesson, the survey found, has been better learned in Florida, where residents are less likely to evacuate when warned (83 percent), but more than seven out of 10 residents (71 percent) prepare for hurricane season.