Rainwater Harvesting (aka water catchment)

Collecting rainwater from your roof is a great way to divert water from hardscaping (houses, driveways, and roads) to use in your landscaping and allow the water to return to the natural water cycle instead of running into storm drains and being treated (or not, depending on where you live) as wastewater. Juan Rapido's friend had two blue barrels hanging out unused and we jumped on the opportunity to grab them and set up our first water catchment system. It's kind of amazing how much water you can collect- Simple Rainwater Harvesting Formula - For every 1” of rain and 1,000 square feet of impermeable surface (roof, driveway, etc), about 620 gallons are generated. Meaning, you can capture about .62 gallons per sq ft. There's plenty of places to read more- here's one.

From past conferences, I knew about a company called Blue Barrel Systems. Reading over their website, I learned that plastic 55-gallon drums that are blue are designated food-grade and only hold food-like items (not chemicals). They coordinate with local companies that have them to sell to you and Blue Barrel sends you a kit containing most (but not all, as we figured out) of the parts you need to set it up. There were a few hiccups around actually reading the directions - so dedicate some time to read them before you start - but the barrels are full and ready to use!

I ordered a 2-barrel system that arrived the next day with on-off valves, a faucet, connectors, and a drainpipe diverter plus glue, pipe tape, and vents. We needed some specific tools that Dad had or you can order with your barrel system, a way to level the barrels (Eric took over building a mini-deck for the barrels on our sloped driveway), 2 concrete blocks per barrel (thanks to the previous homeowners for leaving a bunch behind the garage), and 2.5' of pipe per barrel to make the connections. Buy it in one large piece, though, as you'll need to make many small cuts for all of the connections. They also sell barrel add-on kits if you love your system and want more capacity.

Here's our process: Eric built a deck for the barrels. *Lesson learned: leave enough room for the downspout diverter to reach the side of the rain barrel. Ours is too close to the downspout.

Two concrete blocks per barrel allow the piping to have space underneath the barrels.

Assemble the piping system for the barrels- using a pipe cutter makes cutting PVC pipes easy.

Then glue the parts together.  

And here's the finished system! This took the better part of a Sunday and two trips to the local Ace Hardware store, but it was finished before the rains the next day, and the barrels filled up!

We measured the height of the hose bib to allow a 5-gallon bucket or watering can to fit underneath.

There is an isolation valve between barrels- make sure it's spaced properly so you can reach it.

The kit also came with a drain, which we put on the opposite end of the barrel system from the hose bib. You can also hook up a hose to this so we bought an extra 90* elbow to bring the valve and threads towards the front, where we can reach it.

This is just one type of water catchment system you can set up. We're hoping to incorporate some much larger tanks in other areas of the house. I'm excited to try out the Bushman brand "Slimline" tanks- they come in residential property-friendly colors and are 2' deep and 5.5' tall. The 5' wide ones hold 265 gallons! And if you are a resident of San Francisco, you can get a huge discount on one of these tanks, or a smaller one for free- SFPUC offer via Urban Farmer: check it out!