Editor’s note September 2017: With fall rain showers starting up, we’re re-posting this eleven-year-old (!) favorite from Eric de Place.
Ah, Seattle in November… it’s right up there with Paris in the spring. And this November: what a month! As of the 15th, we’ve broken our record for the rainiest November on record, with 11.64 inches so far.
Speaking of rain and our far-distant spring… this past spring, I succumbed to a fit of eco-grooviness and bought a rain barrel. After all, what could be better than capturing my roof’s rainwater and keeping my plants happy in the summer?
I got a bargain on a 60-gallon orange job from a Seattle Public Utilities program. It was originally used to ship peppers or olives from Greece, and you can still see Cyrillic characters on the side.
I like my rain barrel not because it’s reducing my water consumption—it’s not, at least not in any meaningful way—but because it taught me something elementary about rain in the Northwest. There’s a lot of it.
And there’s a lot of it running off our roofs and driveways. Take, for example, my house, which is fairly “cozy.” (That’s realtor-ese for “small.”) Roughly one-third of my roof—about 300 square feet—drains into the barrel.
Any guesses how many gallons of water come down from that one-third of my roof in a one-inch rainfall?
The answer is roughly 187 gallons, or more than 3 times the capacity of my barrel. That means that this month alone, nearly 2,200 gallons of rainwater have passed through my barrel (almost all of it through the overflow hose that feeds into a drain).
In fact, my small city lot has already absorbed or drained or leaked more than 32,000 gallons of water this month. No wonder managing stormwater and rain runoff is such a big deal. No wonder my backyard turned into a mini-Everglades last winter.
All that rainwater actually creates a headache not just for waterlogged lawns, but for urban infrastructure. High-rainfall events lead to toxics and other pollution running off into local waterbodies and degrading their health. All that wet stuff can strain our infrastructure’s drainage capacity, too. And the problem may worsen as urban areas become more dense and therefore more covered with impervious surfaces (which effectively make all the rainfall run off into the drainage system).
So how on earth can we manage all that rainwater? Unfortunately, rain barrels aren’t going to be the answer.
The problem with the venerable rain barrel, as you might guess, is that there’s not much need for it most of the year. The water isn’t drinkable (because it’s sluiced off the asphalt shingle roof), so it’s useful mostly for watering plants. And from the look of things, my plants have plenty of water right about now. In the Northwest’s dry summer, of course, things are a different matter. Plants need lots of extra water—unless they’re well established and drought tolerant—but then there’s not nearly enough water in the barrel to go around. Maybe what I need is a really, really big barrel.
Actually, that is one of the possible solutions: cisterns. And grassy swales and green roofs and a few other tricks. See this article, for instance. Admittedly, some of these new techniques are expensive and tricky. But then again, the existing drainage infrastructure is also pretty expensive, and it’s not exactly un-complicated either.
In any case, I’ve developed a newfound interest in natural drainage—harvesting the water and treating it like a benefit to the urban ecosystem, instead of a problem that needs gold-plated solutions to manage.
This has been the first edition of Things Eric Has Learned From His Rain Barrel. Tune in next week when the rain barrel teaches Eric how to speak conversational Greek.
UPDATE 11/17/06: A rather hilarious take on this post over at the Seattlest.