This is the completed version of the Rainwater Harvesting project, from catchment to drip emitters. The first part of the post is not new to some of you, but the second part includes the pump installation, pvc lines, and emitters. To view a larger version of a picture, just click on the picture.
Two 2500 gallon tanks fit perfectly on a 16 foot trailer with low sides. I used four 25 foot, 2” racket straps. Highway driving requires additional support (tail gate, board, smaller strap) to keep tanks from sliding back. The tanks weigh approximately 300 pounds each, but can be slid along the dry grass by putting your shoulder into it and bumping them or using a couple of 2×4 boards like train tracks to slide them on.
Locate your water source, slide the tank into place to make sure the height of gutter to tank has enough of a drop, then the surface needs to be leveled. 1-gallon of water weights a little more than 8 pounds, so make sure the full tank remains level and doesn’t go anywhere. A cement slab is best, but if you have sandy loam soil like I do, just put sand on top to level the surface.
I have seen several formulas but this one seems to calculate closer to the middle of the various formula totals I have tried: “square footage of roof area X .6 = gallons per 1 inch of rain.” This roof is 23’x60’or 1380 square feet area of collection. One inch of rain should = 828 gallons.
I extended the roof on the shop for the second tank. This roof is 20’x35’ or 700 square feet.
The rain gutter to water tank plumbing is constructed with 3 inch, 40 schedule PVC pipe. The pipe going down the side of the tank is a “First Flush” pipe with clean out. The first flush needs to be cleaned after each rain event.