Water, Part 3: Rain, Rain, Stay Right Here

Today's a very rainy day on the farm and it has me thinking a lot about water again. I wrote some posts on my previous blog about water so I thought I'd re-post them here and continue with the theme.

Original post: 12/22/2010

The rainy season has officially arrived and I of course waited until the last minute to put some things together that I was planning to get to all summer. But I finally completed the projects and can now add another part to the series. This part on water has to do with rainwater harvesting. I think I initially heard of rainwater harvesting in my first green building course and it immediately intrigued me but it's taken five years to do anything with it.

October of last year my father and I went out to Benicia to pick up a couple of used food barrels, which I intended to convert to rain barrels. This year I built a platform with room for three so I need to go back for another. With some parts from The Urban Farmer Store in Richmond I added valves and tubing connecting the two together and then cut off one of our downspouts and added a diverter with a built-in first flush system. With a few pieces of PVC I connected the supply pipe and I was ready to harvest some rainwater.

You can see the diverter at the cut downspout. The first flush continues down and then turns 90 degrees to daylight a ways from the house. The barrel overflow also connects into this pipe with a T fitting.

We've had a few good storms and the barrels are already filled, probably about 100 gallons. But now what do I do with the water? It's still the rainy season and will be for awhile so I don't need the water for anything outside. And herein lies the problem with harvesting rainwater in this area. When you need the water is during the dry season, but 100 gallons won't last very long during that time. So storage becomes the key element and one hundred gallons just won't cut it. We're talking about needing storage for hundreds of gallons if you were going to keep it to outside use; and if we start considering indoor use as a possibility, it gets into thousands of gallons. Indoor use isn't on the near horizon since that would involve some complex plumbing but I would like to have more storage for outside use so it's either a lot more barrels or look into some large storage tanks. I've seen some cube shaped containers used for cooking oil that hold a few hundred gallons and have a metal cage on the outside making them stackable so maybe a few of those along the side of the house.

Right now this is all a bit experimental for me but there is a potential for serious harvesting and if you can manage the storage, you could theoretically get off the water grid. At the moment the only legal indoor use for harvested rainwater is for toilets and possibly laundry. But with a metal or clay tile roof, the harvested rainwater would be safe enough to drink and could then be used for showers, sinks, dishes, etc. I don't know if I'd ever go that far but I like the idea of it.