This year we are living up to our name on Dry Ridge. While some in the area have been getting some occasional rain we have had less than a half an inch in over 3 weeks. Water awareness is peaked. A few years ago I realized that pumping water was energy intensive when I plugged a kilowatt meter into our water feature pond.( http://bit.ly/1pumZ1q ) . It used more than our refrigerator. We quickly put it on a timer and then learned that having plenty of plant cover and an appropriate population of fish we did not need to pump at all after the spring algae bloom.
We also installed 2, 275 gallon cisterns. These were recycled vegetable oil shipping containers that are available for about $150 through Craigslist. That was the cheapest per gallon cistern we could find though a Septic tank delivered from Southern Concrete is $539 for 1250 gallons, which is cheaper per gallon. Both need work when you get them. Our plastic vegetable tank needs a protective paint or cover to avoid photo degrading as well as adapting the plumbing. The septic tank needs waterproofing and plumbing adaptations and an electric pump if it is buried. Our smaller lighter tank is easy to move around and set up near a downspout whereas the precast concrete tank needs a prepared level surface or a hole if it is to be buried below ground. It also has to be in a place a delivery truck can off load it. There are also a huge variety of rain barrels and plastic tanks for above ground and below ground installations. They are usually a little over $1. Per gallon of capacity. http://www.ntotank.com/ http://www.tank-depot.com/product.aspx?id=130 Our neighbor had a 1200 gallon septic tank installed with an electric pump and rainwater collection plumbing all included for about $2000. There are companies that will install complete systems in our area.
Last year when we got 74 inches of rain or almost twice our normal rainfall of 38 inches, our 550 gallons of storage looked like overkill. This year they barely make a dent in our watering budget. We have approximately 3000 sq ft of garden including berries and vegetables and not accounting for a lot of ornamentals. We have chosen a lot of ornamentals that are drought tolerant but fruits and vegetables want at least an inch a week and when it is this dry at least twice a week. We are able to gravity feed from our cisterns so it is a great energy saver when they can substitute for our well pump. Lately not so much.
I figure we are watering about an hour a day average . I got this rule of thumb estimate of electric usage for our pump. “ People often have a 3/4hp (running 30 minutes a day) that uses 30 kwh per month.” http://bit.ly/T3pWuP If we assume we double that or more depending on when we get some rain that is 60 Kwh added to our normal household pumping. Our average Kwh per month is 257 for everything so that is a 23% increase. That makes bigger look better right now for a cistern.
Climate change is a wild card in terms of precipitation. From the map below it looks like we will not change too much in terms of precipitation but today I have to go pump water from our well to keep the garden from composting before its time.