Brisbane received twelve inches of rain within one twenty-four-hour period and, as a result, both the city and a large area far beyond the city limits were flooded and disconnected from the rest of the country.
Australia is quite well acquainted with extremes of climate. It has a very large desert area and its location in a tropical zone means it gets the full effect of the unexpected heavy rains and high temperatures that are commonplace in that part of the world. During the summer of 1974, there happened to be one of the wettest seasons that Australia had ever known. The climatic variation called La Niina had been one of the most extreme of the entire twentieth century. As result of both of these conditions, rainfall was torrential and continuous through most of January 1974, as the inter-tropical zone settled over northern Australia.
On January 25 of that same year, Cyclone Wanda moved over the interior of Queensland and New South Wales, dumping more than twelve inches of rain in twenty-four hours over a very wide area. As a result, because of the desert conditions commonplace in Australia, massive flooding occurred on all the nearby river systems because of the lack of soil and vegetation to absorb excessive rainfall.
The city of Brisbane was the worst hit. It had not experienced a major flood for more than seventy years and few suspected that anything like this would ever happen. Sadly, after the last occasion when a major flood had hit the city, in 1893, very strict regulations were established for building on areas below a certain elevation. These restrictions were laid out for the parts of the city that would be at risk in the event of a major flood. These regulations were not maintained for one reason or another and subdivisions were allowed to develop on the areas on which no homes or other buildings were to be built. It is a story that is similar to what we have seen in the aftermath of the San Francisco earthquake, where areas that should never have been built on were once again rebuilt.
Throughout Brisbane on January 25 there was a general collapse of disaster warnings. There was no central authority that was able to receive details on the amount of flooding that occurred in different areas, so that local flooding in key areas were never notified to the authorities. About 70 percent of the residents who were questioned afterwards about the flood said that they had received no official warning whatsoever.
January 25, 1974, will be remembered as the time of the worst urban floods that Australia had ever known. Flooding covered an area slightly larger than the entire drainage basin of the Mississippi River. It reached from the dry interior at Alice Springs to the Pacific Ocean and from the extreme north of the country to the areas around Sidney, including the Murray River system. Military air lifts had to be arranged to supply isolated towns that were all cut off by the floodwaters so that emergency food for both humans and animals could be provided by air. In Brisbane all bridges across the Brisbane River were damaged or destroyed and thirty-five people had drowned. At its height, the river broke its bank and ran through the central business district of the city. In one of the subdivisions 1,200 homes were destroyed. Overall, 20,000 people were left homeless.
There was no adequate relief organization at this time and about half of the victims depended on church contacts and a large number of volunteers for the help that they did receive. By the end of January much of Australia, normally the dry continent, had vast areas of the inland submerged in water or weeks. Crops were destroyed and there were outbreaks of disease.
Major flooding is not a frequent event in Australia so the disasters of January 1974 stand out in the history of the country. Elsewhere in the world, especially in the mid latitudes, flooding is often experienced. The Mississippi River drainage basin is one of the largest in the world and the largest in North America. Floods have been a constant feature of it since historical records began to be kept, about two hundred years ago. In the early part of that period, perhaps because state rights have always been a top priority in the political life of America, floods on the Mississippi were regarded as the responsibilities of the states affected despite the obvious fact that no state could control conditions up river in other states. All that changed after 1927 when a massive flood occurred.
It began when heavy rains pounded the central basin of the Mississippi in the summer of 1926. By September, the Mississippi’s tributaries in Kansas and Iowa were swollen to capacity. On New Year’s Day 1927, the Cumberland River at Nashville topped levees at 56.2 feet. The Mississippi River broke out of its levee system in 145 places and flooded 27,000 square miles. The area was inundated up to a depth of thirty feet. The flood caused over $400 million in damages and killed 246 people in seven states. Arkansas, Illinois, Kentucky, Louisiana, Mississippi, and Tennessee were all affected. Arkansas was hardest hit, with 14 percent of its territory covered by floodwaters. By May of 1927 the Mississippi River below Memphis, Tennessee reached a width of sixty miles.
The Flood Control Act of 1928 brought the problem of Mississippi floods under joint federal and state control. About 1,800 miles of levees and floodwalls were built along the river’s course and floodways were provided to divert water into storage areas or into the Gulf of Mexico. For a time it seemed that these measures were a solution to the problem of repeated flooding but subsequent floods proved that there was no single set of solutions to Mississippi River flooding. The flood of 1993 was far bigger and more destructive that the 1927 flood. It was among the costliest and devastating ever to have occurred in the United States, with $15 billion in damages, an area of flood around 750 miles in length, five hundred miles in width, and with a total flood area of 500,000 square miles.
Some locations on the Mississippi River flooded for almost two hundred days while locations on the Missouri neared 100 days. On the Mississippi, Grafton, Illinois, recorded flooding for 195 days, Clarksville, Missouri, for 187 days, Winfield, Missouri, for 183 days, Hannibal, Missouri, for 174 days, and Quincy, Illinois, for 152 days. The Missouri River was above flood stage for sixty-two days in Jefferson City, Missouri, seventy- seven days at Hermann, Missouri; and for ninety-four days at St. Charles in the St. Louis metropolitan area. On October 7, the Mississippi River at St. Louis finally dropped below flood stage–103 days after it began. Approximately 10,000 homes were destroyed as a result of the flooding, with fifteen million acres of farmland inundated, and the whole towns of Valmeyer, Illinois, and Rhineland, Missouri, had to be relocated to higher ground. The floods cost twenty-eight lives and fifteen billion dollars in damages.
If the Mississippi is the main source of flooding in the United States then the Hwang Ho is the principal location for China’s tragic history of floods. Officially it is named Hwanghe but, because of its tragic history of floods it is often referred to as the river of sorrow. It has another name too, the Yellow River, and this is the name that best explains the cause of frequent flooding. Along its extensive course it travels through territory where the yellow loess soil is dominant. This soil is easily eroded and then transported by the river.
From time to time the amount of soil that builds up in the bed of the river raises the level of the river. A sudden rainfall can then push the river to overtop its levees and flooding occurs. The Yellow River has overtopped its banks ten times within the historic record, often changing course later as it resumes its flow. Historically, after each flooding, the levees are raised to ensure that the next big rainfall will not allow the river to burst its banks. As a result of these successive increases in the height of levees the river flows across the farmland at a high elevation above the surrounding territory. Thus, when a flood occurs thousands of square miles are flooded and hundreds of thousands of people are drowned. Even as recently as 1887 a single flood took the lives of a million people.