Q. My father and I are thinking about setting up a pond. It will be about 15 feet long, 9 feet wide and 3 feet deep. Can we dig this pond by hand? Renting a backhoe is very expensive. Also, can we find pond liners this large? Thanks, I find your magazine very helpful.
A. Well, I don’t know if your father is going to like this answer, but yes you certainly can dig out this pond by hand. In fact, all four of my ponds were dug by hand. It takes time and patience — this kind of task is not a weekend project. It may take a month or more to get the hole the way you want it. Here in New England we often have to pry through large stone boulders.
I estimate that your planned pond should hold about 2000 to 2500 gallons depending on the shape. This is a good stable pond size. The 3-foot depth will make it very attractive for koi and goldfish.
You should have no problem finding a liner for your pond. The rule of thumb for estimating liner size is to add double the depth to the length and the width, and then add another 2 feet to each dimension. So you will need a liner that is 23 feet long (15+6+2) and 17 feet wide (9+6+2). Because I am a very cautious guy, I often add yet another foot to the final size, which would make your liner 24 feet by 18 feet.
Depending on your choice of material, the liner may cost between $150 and $500. The Permalon multi-ply liners sold by Reef Industries (Houston, TX) may last a decade or more and are priced at the lower end of the scale. These are very strong and easy to work with. Three of my four ponds use these liners.
PVC liners, such as those sold by Tetra, are also intended to last about 10 years and are priced in the middle of the scale. I have used these extensively and always with good results.
The new fish-grade EPDM liners are priced at the higher end. They are alleged to last 20 years, though this is a theoretical lifetime. Nevertheless, they are incredibly strong. Even at $500 for 10 years the cost is an insignificant $50 per year. You will certainly spend more on fish food alone.
I suggest you take a look at the three books I mention in the reply to the final letter. Tetra also puts out a handy little booklet — Digest for a Successful Pond (ADI 52) — that you can pick up at your local aquarium store. Good luck digging.