While the history of the barrel goes back to Babylon and Roman times and the rain water barrel would have to follow that , the history of rainwater harvesting very possibly would date back to the very first appearance of “Man”. It is quite likely that the “cave man” collected rain water for future use. Exactly how he did this is something which we will probably never know for sure, but we can make theories and theories are always fuel for the creative mind. Most likely they used animal skins to catch the water but who knows for sure.
Before the advent of the wooden barrel there was the “clay barrel” or urn. The first uses of such containers may have been for wine and oils, however it is quite likely they would have been used for collecting rain water, since in India in the 3rd century B.C. there is not only mention of rainwater harvesting, but there is also a note that “Members of the community who did not participate in the activities of water management were punished.”* I have no idea what this punishment may have been but I’d be willing to wager that it was more severe than the fine you might be subjected to in Southern California for violating the water conservation rules.
In Ethiopia there is record of rainwater harvesting being used as early as 560 B.C., but the earliest recorded use of rainwater harvesting pre-dates this by thousands of years. In Southern Mesopotamia there is evidence of water harvesting dating back to 4500 B.C. The barrel didn’t come into use in the Roman Empire until about 300 AD, though they had been used by the Gauls for a few hundred years, so you can see that the rainwater barrel was late in the evolution of rainwater harvesting. The exact date when wooden barrels were first used to capture rainwater is unknown but one might assume that it was not long after barrels became commonly used.
When we think of barrels we think of the cylindrical container, but it also became a unit of measure in the English system and though it varied over time it was generally between 31 and 42 gallons. Barrels were the preferred shipping container for about 2000 years before the advent of metal drums and cardboard containers. Barrels were used to ship everything from gold coins and nails to fine wines and whiskey. Since they were so common and able to hold liquids they became ideal for capturing rain water. If you see an old Western you often will see a rainwater barrel in the back ground that was probably left over from something that had been shipped much like old cardboard boxes are today.
With the advance in technology today most “rainwater barrels” are made of plastic and come in all sizes and shapes from the traditional barrel to shapes resembling a child’s building block The most un-traditional of these is an Australian innovation called the Rainwater HOG, which was invented by Sally Dominguez, an Australian inventor and architect. It has a unique look very unlike a traditional barrel shape. It is shaped a bit like “Gumby” or a green domino. Most others are shaped like barrels or tanks but, being plastic, there has been a bit of creativity in their look. I only mention the “HOG” because of the unusual name and the fact that it was actually designed for appearance and functionality by an architect.
Today in Southern California there is a water shortage, in spite of the fact that there seems to have been rain. The reason is that the rain went down the storm drains and into the ocean and very little stayed behind. Utilizing rainwater harvesting would help in many ways. While you probably would not want to drink the rainwater for a variety of reasons from roof contaminants to just what is washed out of the air in the LA area, but there are many water uses from watering your lawn to washing the car where a rainwater collection system would be just what the doctor ordered. If you own a golf course you could have “green” greens, if you’ll excuse the bad humor. The point is that saving rain water for future use was good for the Southern Mesopotamians and it is still a good idea for Southern Californians.