There were a few articles in the press in the Fall of 2007 about using rainbarrels to help some communities deal with flooding caused by decaying storm sewer systems. Some local governments were even offering rainbarrels 'at cost' to residents. Will this really work? Can putting a rainbarrel next to everyone's house in a community at a cost of $55 per rainbarrel payed to the local government and/or their friends in the rainbarrel making business really fix the flooding problems?

Well I did a little thinking and a little math and came up with the answer no. The only thing that will happen is the rainbarrel makers will get rich and you will have something attached to your house that is great for watering your garden in times of drought, and may be great at giving you better garden water than you can get from the local water supply. If you live in certain areas of this city, you will also help your government save a little on sewage treatment costs.

First. Rainbarrels are not designed to be used as a storm surge buffer. They are designed to capture and hold water for later use. If you want something to capture water to take the edge off a storm surge, ideally it would be empty when the storm starts. Rainbarrels are supposed to be as full as possible so you have water when that drought hits. I suppose you could run outside and empty it when you see a storm coming, but if rainbarrels could really hold enough water to offset a storm surge, everyone emptying their rainbarrels at once would be just as bad as the storm.

Second. Most of the rain does not hit your roof, and therefore will not end up in a rainbarrel attached to a drainspout. The roof area of my parents house is about 1/8 the area of the yard so only 12.5% of the rain can be captured in rainbarrels in their yard. 87% of the rain hitting their house would still end up in the storm surge.

Third, you would need a rainbarrel on each drainspout on your house. I think for my parent's house this would be 4, raising the cost of those local government's solution to over $220 per house.

Fourth, a rainbarrel only holds 55 to 60 gallons of water. It sounds like a lot, but a big storm drops a lot more rain than that on your roof. 1 inch of rain landing on my parent's roof is actually (here comes the math:)

• 1200 sq feet/roof
• x 144 sq inches/sq foot
• x 1 inch of rain
• x 1 gallon/ 231 cubic inches
• ----------------------------
• = about 748 gallons

You would need about 12 empty rainbarrels just to capture the first inch of rain landing on the roof.

Instead of spending $660 per house per inch of storm surge rain on government 'at cost' rainbarrels, only to miss most of the the rain not hitting roofs, why not put that money into fixing the storm sewer systems, or on some other community based solution? And if you are going to get a rainbarrel, why not make one yourself for less, or get a pretty one for watering your yard from one of the vendors listed below for about the same money. One that will go nicely with your yard.

Oh where oh where does the water go?
When it begins to rain, it begins to flow.
Off the roof, yard and down the street,
It goes downhill until something it does meet.