Farm Pond Design: Water Storage on the Homestead
A Pond on Your Homestead Can Serve as an Excellent Off-Grid Water System
By Jeff Hoard – A well-planned farm pond design can add pleasure and productivity to your land. It provides a calm, peaceful area to relax, fish, etc. We also use ours in a practical way, to irrigate plants, which keeps the water moving and cleaner. Some safeguards could be put in place to allow for swimming but we didn’t do that. You might be interested in the inexpensive way we made our 20′ x 70′ pond, (a.k.a. Lake Hoarding Water).
Fortunately for us, we have a high point on our property. It looks flat out here, but it isn’t. To get the most out of a pond, a high point would be the first thing to find. The reason is that we gravity feed that water onto the lawn, gardens and trees. Why pump it if it will gravity feed by itself? Sure, things don’t get watered as fast, but the slow pace fits in good with our lifestyle. And during those times when I forget to move the hose, the low volume doesn’t leave me with a huge mess. The pond does not have to be much higher for this to work. Actually the bottom of our pond is lower than what we irrigate. Since we have fish in ours, under no circumstance do we want the pond to completely empty. Having the bottom lower ensures that won’t happen.
Being off-grid and using wind pumps, we need water storage. In addition, being cheap, we want free fertilizer, and that’s where the fish come in. You may be wondering how does wind energy work with a farm pond design? Basically, wind pumps fill the pond and the irrigation system ensures the plants get a mild shot of fertilizer each time they are watered. Matter of fact, although I add humus I haven’t had to fertilize in three years. We grow melons, potatoes and other assorted vegetables and sell them locally. Each year in the last three years the soil test showed high nutrients.
One thing I have done however is add a little ironite to the soil. It is basically just trace elements and minerals. The fertilizer isn’t completely free; we do feed the fish but probably only about 1/4 cup per day. We found that inexpensive dry cat food has virtually the same nutrient value as fish food and is a lot cheaper. In this cold climate we can only raise goldfish. Our pond is frozen over at least two months each year, and without proper farm pond maintenance to ward off winterkill, goldfish are the only breed that survives. We initially put in 23 and now have more than 1,000 of all different sizes (I measured one at 9 1/2″ long!) I’ll let kids fish when they’re here. I always keep a couple of kids’ poles ready to go. The fish poop and oils will plug a slow leak if one occurs.
Folks in milder climates could raise a lot of meat in a pond the size of ours, used the way we use ours. For this to work, however, you have to have a farm pond design where old water is used and replenished with fresh water. Our wind pumps are perfect for this since they pump air. The air-line is fed down the well to the bottom of the supply line and is inserted up inside the supply line about three feet. The air is released inside the supply line, which aerates the water and makes it “lighter.” The well water rushes in the bottom of the supply line to take its place, which sends the aerated water up and out of the well. This is very good for growing fish.
Other methods can accomplish aeration also; something as simple as the fill water splashing on rocks (a waterfall effect) is all that is needed. Just try to locate the entry and exit at opposite ends (as much as possible).
I guess I’ve said enough about the pond’s role here at HM Ranch (which is significant). Now I should explain the farm pond design. Fortunately for us, when we bought this homesteading land there was already a depression at the high end (again, not higher by much). I was in the process of digging this deeper by hand (knowing it would take a while). A neighbor saw me digging one day and insisted that I use his backhoe. I’m not one to borrow things so I declined his kind offer but about two hours later he brought it anyway. I decided to go ahead and finish digging with the backhoe, but this kind of came back to bite me in the end, as I’ll explain later. Once the pond was dug (I dug it one foot deeper and two feet wider and longer than we expected the finished dimensions to be), I dug in PVC water lines. One is a 4″ line and two are 1″ lines. These ultimately lead to various areas (gardens, lawn, trees and stock tanks). I hand dug trenches for the water lines down to where I felt was the absolute lowest level we ever wanted the pond to get (to date we’ve never been even close to that level). These pipes should stick out only about 3″ into the pond during construction: this makes it easier and more accurate when installing the liner.
For our farm pond design, I installed a ball valve and stand pipe on the back bank. A valve obviously needs to be installed on each pipe. I put ours down in the ground at that point because of the hard winter freezes here. The 1″ PVC ball valves are fairly cheap. The 4″ brass valve was not! But for our situation, it was needed. In other situations, it may not be necessary.
After these lines were installed we covered them and repacked the dirt. After that we smoothed the inside of the pond dirt and, the absolute most important thing for our farm pond design, we removed all of the surface rocks (these can puncture the plastic sheeting) before we laid 8 ml plastic down as the liner. We bought this at the local hardware store. It doesn’t have to be one giant sheet of plastic, we just put a bead of 100% silicone caulk at the 2′ overlaps. It won’t adhere to the plastic but it does provide a seal. When you get to the pipes you have to gauge the circular cuts. I cut pairs of 6″ x 6″ pieces of plastic (these can be anything, even coffee can lids). Install one on the pipe before laying the liner and the other after the liner. Be sure to caulk the one that will face the water and screw these together. Push these up against the pond’s side and caulk around the pipe real good (see diagram below).
Make sure that the top of the liner goes past the edge of the pond a few feet for your farm pond design. On the rim of the pond, I installed wood slats (3′ x 1-1/2″ x 1/4″). I took each slat and drilled a 1/8″ hole at each end and smoothed down any sharp edges. It took many 8″ pieces of galvanized wire (equal to the diameter of coat hanger wire). Half an inch from the end I bent the wire 90 degrees (see diagram of our farm pond design). I laid the slats along the top ridge (a few inches below the side height) around the complete circumference of the pond. Inserted through the holes, I hammered these wires into the dirt to hold it. Then we just laid the excess sheeting back over the slats so the top edge is double thickness (see diagram).
Now it is time to add lengths to the exit pipes. If you can’t reach over the side to lengthen these pipes you’ll have to, very carefully, walk inside, being very careful not to damage the liner. (Obviously, this entire step needs to be done in calm weather.) The 1″ PVC pipes are rigged into the pond. I put a cap on a 2′ piece of pipe and then drilled a series of 1/4″ holes right at the end. This just serves to screen objects out. The 4″ line sticks out about 6′. On the 4″ line, I installed two slips to thread 90-degree elbows and tied a float to the tip of the intake. The float keeps it off the bottom but still far under the ice in the winter (it hangs about midway). This 4″ line has a screen on it and that is the reason for the threaded elbow. With a small rope tied to it, I can lift it up and out of the water to clean it.
Now comes the most labor-intensive part of executing on our farm pond design. The entire liner needs to be covered with a minimum of one foot of dirt. Try to use dirt with as few rocks as possible in the first layer. If you have a choice of dirt type, obviously clay would be the first choice, but it doesn’t have to be. We used the same dirt that we dug out. This really needs to be done by hand because large bucket loads of dirt dumped from a loader can easily damage the liner. Anytime you see damage just clean the area up and lay another piece of plastic over the area and cover it with dirt. To protect from wind gusts I would try to get a one-inch layer of dirt on the entire liner. At that point, you are out of danger and the rest can be covered in your spare time. Again, you need one-foot minimum coverage.
Earlier I mentioned that digging out our pond with the backhoe came back to bite me. I dug the sides of our pond a little too steep and had to add more dirt than I should have just to get it up to the top. The plastic does not hold the dirt; it just slides right down. Our pond is probably 7′ deep in the center and 8′ wide at the bottom and only about 20′ wide at the top. I just kept adding dirt until it eventually filled up. I certainly wouldn’t recommend that steep of a side angle. With the side dirt, I mixed in some old grass seed that we had. I’m sure that the sprouting served to stabilize the dirt pack until natural plants grew.
If your farm pond design will be used for swimming, now would be the time to lay down flat shale type rocks in the bottom and also at the point of entry. A dog or person clawing their way out would surely damage the liner if it were unprotected.
But now it is ready to fill. You want to fill slowly so the dirt stays where it is supposed to. As it fills and the sides get muddy they will settle and slide down some. Just keep adding dirt to the top. You might even have to do this in a month or so but it will eventually stop settling. The grass we planted in the side dirt eventually made a nice tough rim. The water will be really dirty at first. As soon as we saw some clarity we added our fish. The goldfish can handle dirty water, most other species cannot. If you plan on putting some other fish in it I would still put the goldfish in first. My guess is that any other sport fish would eventually take over. I do not recommend ducks as ours nibbled on the sides constantly, plus they ate all of the fish food and just generally caused problems, so we gave them away.
Our pond has been in for about four years now and we have had no problems thus far and I don’t anticipate any. I figure our entire cost for the pond itself was about $200. Pretty reasonable for what we have gotten out of it. Of course, there was a lot of shovel work. Even if you hired a backhoe and operator he/she could dig out a lot of dirt in just a couple of hours. Like you probably, I was leery about using 8 ml plastic sheeting, but I’ve dug up plastic that has been in the ground for years and it still has the pliability of new sheeting. As long as it can be kept out of the sun it lasts for a long, long time. By the time the plastic starts to deteriorate you should have a thick, slimy jelly oily-like substance coating the inside of your pond and this a natural seal. This gives a recreational, peaceful, practical, resource producing element to a homestead. Plus, this is perfect for organic gardeners since the fertilizer is all natural and again I’ll mention the large amount of fresh fish that can be raised in a pond the size of ours. So I’d recommend putting together your farm pond design, staking out your measurements, grabbing your shovel and getting after it. The sooner you start, the sooner you’ll be done!
Originally published in Countryside March / April 2010 and regularly vetted for accuracy.