Up until very recently, I've never lived anywhere where I had the space to set up an outdoor garden. I've been fortunate to finally own a property where I can, and I'm really enjoying it. So far I've set up an 8 x 25 garden plot, planted 4 fruit trees, and have a thriving wildflower garden in front of the house. I have a lot to learn, but I'm certainly enjoying the process.
One of my recent projects has been to install gutters on my workshop; it's a 25x50ft building. That got me thinking; why not collect the water from the gutters? I live an area that gets near-constant rain in the fall, winter, and spring, but it turns into a desert here during the summer. We haven't had more than a light mist in about a month or more. I have a roughly 60x20ft section of property hidden behind the shop, and it would be a perfect place to set up some IBC totes to collect the water.
For those of you who collect rain water for your garden, how much do you find you need/use? Based on my water bill, it looks like my usage went up by about 75 gallons per month since I've started gardening. I figure round that to 100G just to be safe; for 4 months with little rainfall, that would mean I need about 400G stored. I tend to over-engineer everything I build, so lets double that to 800G.
I'd enjoy hearing from anyone who harvests rainwater for their garden. How much water storage do you have? Do you find it's too much, not enough, or exactly what you need?
Yeah 150 gallon total but it's definitely not enough to get me though even a couple weeks of watering if I were to rely on it. I probably use close to 60g to water all my garden once and that gets me 2-3 days before I need to water again. And we get pretty much no rain during the summer months, maybe a sprinkle but not enough to fill the barrels.
I've been looking at how to get pumps setup, the problem is it's 3 independent barrels so I'd need 3 pumps and then power. Also unsure if I want to retrofit a submersible pump or use inline on the existing spout.
I don't know how your barrels are set up, but you should only need one pump. Assuming you have a place to make all 3 barrels level with each other, you can install an output at the base of each barrel and connect all three together. When you collect water in one barrel, it increases the downward pressure of the water in that barrel, and it will equalize across the other two; filling one barrel actually fills all 3. Then just install a tap on connection between the 3 barrels and route it to a pump (I'd recommend a particulate filter first so you don't jam up the pump). When you pump water out, the inverse happens; all 3 barrels will drain equally. Even if your barrels are far apart, as long as you can keep them level with each other, this should still work as long as you're willing to run plumbing between them.
Personally, I'd prefer an inline pump rather than submersible. Not only is maintenance on the pump easier, but you also don't have to worry about running electricity into one of the barrels; I'm sure submersible pumps are safe, but you'd still have to cut an opening in the barrel for your power cables, which is a pain in the ass.
As far as power goes, as long as you can position the pump close to a structure with power, you just need to make sure you use liquid-tight conduit between the outer wall of the structure and the pump. If you want an outdoor switch for the pump, this would need to be an a liquid-tight enclosure. While it's almost certainly not to code, you could probably just install a 1-15P plug on the cable inside the structure and plug it into an outlet and have no issues. FYI: I'm not an electrician, just someone who's done a lot of electrical work.
Edit: I just realized that my comments about electrical are very US-centric; if you're not in the USA, it's probably a good idea to disregard everything I just said.