First we got the guttering up, which, with the help of the scaffolding, was actually pretty easy to install.
Once this was up we put one of our 1,500 gallon tanks place at one end of the shop and attached the run off pipes.
The calculation is -
A * R/12 =cubic feet/year
cubic feet * 7.43 = gallons/year
where A = Area of catchment in square feet and R = Inches of rain you get a year
So when we did our calculations we got 3,000 gallons per year that we would be able to capture off of the roof top. And we receive all that rain in the space of about 3 months so one 1,500 gallon tank was not going to be enough - Enter tank #2.
We have tank #2 here, it just needs a clean out and to be put in place and piped into the gutter on that side of the shop. We will need to relocate the diesel tank somewhere else, but it will be great to have 3,000 gallons of water storage.
We did have our first huge rain storm 2 days after we installed the system. It was great to see it doing its job and watch that huge tank fill up with water. We got 500 gallons in 3 hours, but I will say, it was QUITE a rain storm.
Now please note that these tanks are WHITE!! Duh, you say. You cannot store potable water in white tanks as these are more susceptible to algae growth. Also, we are not doing any extra filtration system on the rainwater we catch beyond a basic household water filter. This water will just be for toilet flushing and washing and cleaning. We will be installing another tank for storing potable water from our spring on the other side of the property that will be a special green tank and since its already the spring water we drink at the house we won't need to filter it like we would rainwater.
But even if you don't live in a drought ridden area like CA, think about a small rainwater collection system. How great would it be to have a green lawn all summer and a clean car and not put any added pressure on your well or town's water supply. Its so easy to do and so nice to have that little reserve for a non-rainy day.