Just for fun, let’s be a little controversial - who owns the water that falls on your roof or land? To tell the truth I haven’t got a clue and I really don’t care but there are others out there who do. Believe it or not there are some states where it is illegal to catch rainwater and others that require a permit. I live in Washington State. A few years ago it was illegal. Now it is legal but anything over 3500 gallons requires a permit. If you don’t believe me just do a Google search and you will discover a lot of information on rainwater ownership from reputable websites like Popular Mechanics or even the New York Times. I’m sure there is a whole philosophical and legal debate to be done on the subject but not on this Blog if I can help it. Just be aware that if you do entertain ideas about catching your rainwater, you may want to check with your local authorities before you make any effort or spend any money.
We use rainwater we capture from the roof of the house to water our garden. If we aren’t using it for that we have a built in overflow that carries any extra water away from the house to a natural depression where the local wildlife can enjoy a fresh drink while wandering through. We use the water from the barn roof to water the horses all year long. Doing that helps to lighten the load on our solar powered electrical system. That is a lot of water we don’t have to pump with solar power all year long. The horses can use up to 10 gallons per day per horse. That’s 7,300 gallons per year. To keep the water use down for the garden we water by hand instead of blanket sprinkling. Last year we were able to water the whole season from just our cisterns.
When we built the house I contacted a local septic tank manufacturer who was open to the idea of a custom designed tank. I sketched out what I wanted on a piece of paper and they adapted my changes to one of their standard designs. I just gave them pipe sizes and locations for the entry, exit, and overflow pipes that I was going to use. I ran a PVC tight line underground from the downspouts to the tanks which I also put underground. Our garden is downhill from the house so it utilizes a natural gravity flow. The tank at the barn requires us to use an old fashioned rope and bucket retrieval method.
Our tanks are made of concrete. Most of the tanks sold today are made of plastic. I couldn’t recommend either one to be the best. They both have advantages. Concrete tanks are more susceptible to cracking than plastic but will probably last longer. Also, if you do develop a crack, there are products on the market now that work really well and are easy to apply.
My tanks are underground but they don’t have to be. You can use above ground tanks all year long in the right climate or you can use them seasonally to help water your flower beds etc .if that works best for you. There are many plastic above ground tanks with lids that have a built in adapter for your downspout and a ¾” fitting at the bottom of the tank for your garden hose.
No matter what kind or size of cistern you decide on, I do recommend that it be entirely enclosed including the top. It’s safer, more sanitary, and will help reduce evaporation.
Where to find them? You can look them up online or in the phone book under water tanks, cisterns, or even rainwater harvesting tanks. Check with your local feed store or farm supply company.