Water is the life blood of the homestead. Without adequate moisture every aspect of homesteading becomes exponentially more difficult. Access to clean water is becoming more and more costly and difficult. Even if you do have plentiful ground water the cost of drilling a well is going through the roof, add onto that the uncertainty of hitting a good vein and you begin to see the problems inherent in relying on wells as your only water source. But you might say I live in town and get water from the city. Just simply turn the tap and there it is. That’s all fine and well until they start to ration your water and you can’t keep your garden alive. Or the cost of municipal water becomes so great that it is prohibitively expensive to keep a garden or livestock. Not to mention you are relying on “the man” for your water. A big part of homesteading is reducing your dependence on “the man”, it’s awfully hard to be self-sufficient when you’re depending on someone else for what is arguably the most vital aspect to every homestead, and life in general. What’s a kid to do, you might ask. Well for me the answer starts with holding on to every ounce of water that falls from the sky onto your land that you can. I’ve identified three basic water harvesting techniques that every homesteader should know about, and be thinking about implementing on their land.
First off is collecting the rain water that falls onto your roof or other impermeable surfaces on your land. This includes not only your house, but your barn, shop, wood shed, greenhouse, pig shanty… you name it. I’m not talking the old blue 55 gal rain barrel either. Those things are about as useful as… well they’re just not very practical that’s all. To calculate the amount of storage you will need you need to figure out approximately how much rain is going to fall on your roof areas. To do this you apply the simple formula of: Harvested Water (gals)= Catchment area (sq. ft.) X rainfall (in) X 0.623 conversion factor. I know math sucks, but follow me here. Catchment area is basically the square footage
of the building you are harvesting water off of (the single floor foot print), you can add on the area covered by the eaves etc. but I keep it simple and use the square footage of the building. Next you can find your average annual rainfall for your area or you can just figure it for how much water you would get in a 1 inch rain. Then you multiply all of that by the conversion factor, and it will tell you approximately how much water you can potentially harvest from your roofs. For example we have a 2400 square foot shop that we are looking at harvesting the rainfall off of. Our average annual rainfall is 24 inches. For us the formula looks like 2400 X 24 X 0.623 = 35,884.8 gallons of water per year just off of that structure. For just a one inch rain I’d be looking at about 15oo gallons of water off of that building. You see now why I say those cute little 55 gal rain barrels they sell at Home Depot just aren’t very practical for actually harvesting rain water. I’m thinking something like a 10,000 gallon poly water tank would be about right. I think if you are using anything less than a 500 gallon holding tank you are just wasting your effort and money on a project like this. The good news is that poly tanks are relatively inexpensive, and if you already have gutters on your buildings setting up a rainwater catchment system is pretty cheap and easy.
The next technique I want to share with you are on contour swales. This is basically a ditch that is perfectly level across your landscape (on contour). If you think of it as a really long, really skinny pond, that isn’t sealed, then you wouldn’t be too far off. The idea on this one is that you catch water that would normally be running over the surface of your land, stop it, hold it, and let it sink into the soil.
Ideally you would have a series of swales across your landscape starting as high up as you can get a significant catchment. Then as the swales fill up and run over, through a level spillway, you would catch that water in the next swale down hill, and so on all across your property. You could use the formula given above to determine your total water harvest based on your acreage and annual rainfall and layout your swales from there, or you could just wing it. To build swales you need to determine a level contour line across the landscape using a laser level, transit level, A frame level or some other device to get the plane perfectly level. You then dig the swale and place the spoils(dirt) from the ditch onto the downhill side making a mound. Make sure the bottom of the ditch is level. The swales can be as wide and deep as you want, anywhere from six feet on down to two feet is pretty common. The best thing to do from there is plant trees into the mound and seed a heavy cover crop over the whole thing. I don’t want to get into to much detail here(maybe on another post), but that is the basics of a swale.
Finally I’ll give the nod to the good ole’ farm pond. There is a reason why all the old timers always had a pond on the farm. They are the most cost effective means of holding onto massive amounts of water for use on the homestead. All you really need is to find a place that naturally funnels water through, like a small valley, draw, or gully, and build a pond. Pond building is a major undertaking and with the mass of water being held back can be quite dangerous, so consult a professional on this one. Ponds can be used for flood irrigation, livestock water, fishing, and swimming. They are an asset to any homestead where they are appropriate.
Ideally you want to design your water harvesting in an integrated way that would benefit all of the systems you put in place. For example you could divert your excess roof catchment into the swale system( or run water from your roof cisterns into the swales to water those areas), then the swales could feed their overflow into a series of ponds that would overflow into another run of swales that you could flood irrigate out of, and so on. A set up like this would hydrate the landscape, replenish the aquifer, and create lush growth across your property. All of this from the water that falls from the sky. You should be mindful of local laws and ordinances that pertain to rainwater diversion of course, and make sure that you aren’t doing anything dangerous by impounding massive amounts of water with inadequate infrastructure. Being smart about water harvesting can make your land drought proof and mitigate the effects of floods. Good design is the key, plan for 1000 year floods and everything else will be handled easily. With the amount of water that falls from the sky, even in the arid west, there is no reason that every homestead should have to worry about whether or not their crops are going to make it this summer or if the cattle are going to go thirsty. We need to be proactive with hydrating our landscapes. If we do this we are guaranteed resilient abundance and regenerative landscapes.