Watering a big garden on the cheap

Pouring bought water into the ground seems like such a waste.  I don't mind paying for things, but paying to dump something that falls from the sky for free always grates on me, so in my garden I don't do it.  I catch rain when it's falling and water the plants with it when the rain decides not to fall.  Overall it works out well.  I haven't had many times when I ran out of water and desperately needed more.

The water system starts at the house.  I first placed a 55 gallon plastic barrel under the rain spout.  It has an overflow that sends excess water into the storm drain, and a line in the bottom that I can tap the water in the barrel from. 

That worked very well, but Stevens' Fourth Law wasn't satisfied with this (Stevens Fourth Law states that if it's worth doing it's worth over doing).  So I had to take it up a level with four more barrels for a capacity of 250 gallons.  This web page shows how to make the fitting for the bottom of the barrel to get the water out.

Then a step further - a farm pump so I could move the water up to the garden.  The garden is a good 10 feet above the level of the barrels.

That was better, but it still wasn't sufficient.  250 gallons is a good days watering when it's very dry here, and the summers can have stretches of very dry weather.  So clearly I needed more capacity which looks like this to me:

That's three IBC (Intermodal Bulk Containers) which hold 275 gallons each, which brings my total capacity to over 1000 gallons of rain water storage.  The IBCs (or totes) come with an 8" opening on top and a 2" ball valve on the bottom.  I have them piped in so the top one fills and the valves can be opened to let the water drain into either of the other two.  Only one valve is open at a time during watering, so even if I leave a hose running too long I won't lose more than 275 gallons.  I quickly learned the importance of leveling the stacked containers and providing a solid foundation.  When both of the stacked units were full we had a lot of rain, the ground got soft and the tower started to lean a little; then a lot; then the whole thing went over with a fantastic crash.  That's about 1500 lbs of water falling up to 8'.  I'm glad I wasn't anywhere near it when it went.  I set them back up on a solid, leveled foundation, and they're ... well, right as rain.

The totes are made of a plastic that breaks down in sunlight, so I took each plastic tank out of its cage, wrapped it in black plastic like an enormous Christmas present then carefully stuffed it back into the cage.  The top unit has the water just dumping into the 8" opening - the black plastic is pulled up to the PVC pipe and duct taped to it to minimize insect invasions.  On the other two I just drilled a bunch of 1/8" holes in the 8" cap to let the air pressure equalize.

The totes are on the uphill side of the garden, so I can water anywhere with just gravity feed.

The water drains from the tanks through a 1.5" PVC flexible pipe which ties to a Fenco fitting (rubber boot held on with band clamps) to a 1" PVC ball valve to a 3/4" hose fitting. Many hours were spent pondering the possibilities in plumbing aisles across most of the greater Pittsburgh area to come up with the final product.