So, when we last left off the saga of the rainwater harvest garden, I had the two water tanks in place, and the big one neatly on its pad. There was still plenty of work to be done, even so. Since they were predicting the first thunderstorm of the season for Sunday night, I figured I needed to get cracking on it. So on Sunday afternoon I took some time off from writing and course prep to do a little construction.
First I set the little tank up on pavers, partly to make it easier to work the valve for the hose, but mainly because I like the look of varied heights between the two tanks.
Next, to cut the holes in the tank for the overflow pipes, I borrowed a knockout cutter from my neighbor, Tom, who is the only person I know who owns more tools than I do. Here is Tom:
He and his wife Mandy are two of our favorite neighbors.
And here is me using the tool after a helpful tutorial from Tom:
I attached two overflow pipes. The first is one from the small tank, into which the water from the gutter flows, to the larger tank. When the small tank fills, it then overflows into the larger one.
You can see that pipe in this photo, and you can see the neat hole for the second pipe as well:
I offset the holes slightly, with the pipe that flows from the small tank into the larger one a little higher. That way when the big tank fills up, it will start to overflow into the garden instead of backing up into the pipe from the little tank.
The pipes attach by slipping a threaded end through the hole into the tank, and screwing in a thingy against a gasket. Here is a view illustrating that:
Slick. I found these flexible pipes in the plumbing/electrical section of Big Box Hardware. I have no idea what they are really used for.
Here is a view of the tanks with all the pipes in place, looking fairly unobtrusive:
And another view, this one showing the pavers under the little tank:
If I want to, I can attach a hose to the second overflow pipe and direct water further out into the yard during the heaviest rains.
I also took this opportunity to attach a shut-off on the hose that I'll use to distribute the water, as well as a shut-off valve on the big tank (the small tank already had one):
I still needed to make a cover for the big tank, but my break from "real" work had been long enough. The finishing-up will have to take place this weekend. So I left it at that and went on about my business. Later that night the rains came--a good 3/4 of an inch--and water poured off the roof.
After a short period of time, I ran outside to see if the overflow pipes were working:
Mind you, wind is howling, thunder and lightning are crashing all around me, and rain is pouring from the heavens as I take this picture. What I won't do for the blog!
The next morning, I saw this beautiful site:
It is filled right up to the big tank's overflow pipe, so it must have done its job and directed the excess water out into the yard when the tank topped out.
With these two tanks and the two more 75 gallon ones I have on the other side of the house, I collected 300 gallons in one moderate thunderstorm.
Think of all the water I didn't collect--water that rolled down that roof and got away!
I need more tanks. I am practically awash in greediness for them as I write this.