A Guide with Tips to Garden Pond Building

Japanese Style Garden Pond

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A garden pond adds beauty, elegance, and lively interest to a yard. Whether a fish pond, a receiving basin for a waterfall , or simply a placid body of water for meditation and reflection, a garden pond provides a focal point that enhances nearly all yards. But to successfully create a garden pond that looks natural, it helps to follow a few basic guidelines to make the building go smoother, and for easier continued maintenance of the pond.

Level the Garden Pond Perimeter to Close Tolerances

When digging the hole for the garden pond, remember that a garden pond’s water level is only as high as the lowest point of the pond perimeter. In other words, the entire perimeter of the garden pond needs to be as near to the same height as possible. This might be a point that seems obvious from afar, but when you are in the midst of digging the pond it can often escape attention. Since an exact level is not possible, think in terms of deviation and tolerances. For example, if your chosen pond depth is 24 inches, the perimeter’s deviation from that height should be as little as possible: just an inch or two.

Decide Whether the Pond Will be Shallow or Deep

The depth of the garden pond is an important decision that affects both cost and the eventual appearance of the pond. As the pond gets deeper, the bottom becomes less visible and rock cannot be seen. Fish might tuck themselves away, hidden. Deeper ponds also require the use of additional expensive pond liner. Shallow ponds are better for displaying decorative rocks on the bottom and fish are more prominent. But shallow ponds tend to build up algae faster because the light is able to reach more of the water with greater intensity.

Protect the Pond Bottom Against Burrowing Animals

Burrowing pests such as groundhogs and moles can dig up holes in a lawn and garden. When you have a burrowing animal in your yard, it seems like you’re always filling in holes. But the problem goes well past the point of annoying when the burrowing animal exits under your garden pond, chewing away pond liner in the process. The solution is to lay down a metal mesh called hardware cloth as a base for your pond bottom before shovelling a few inches of dirt over it. Then underlayment and liner go on top of the dirt layer. If your sides are dirt, not retaining wall block, then you should lay hardware cloth on the sides, too.

Reconcile Eventual Pond Size With the Pond Liner Size

A garden pond can only be as large as the size of its underlying pond liner. So, you have a number of questions to answer before shovel meets dirt. Quality pond liners made of EPDM are very expensive, while PVC liners are expensive but less so than EPDM. In a project that involves the use of free or low-cost materials such as rock, concrete slabs, retaining wall blocks, and the lowest cost item of all, water, spending hundreds of dollars for a sheet of the liner can be a daunting prospect. If your budget is tight, then the cost of the pond liner will always dictate the size of the pond. On the other hand, you might find that it is worthwhile to put a little extra money into a high-visibility, curb appeal project such as this.

Early Shape Nuances Are Often Lost

When you initially create the shape of the pond, you may find yourself adding special curves and inlets that you feel will give the garden pond a unique look. But these early delicate nuances often get softened and obliterated with each subsequent stage of the pond-building process. Adding underlayment, liner, rocks at the bottom of the pond, and especially rocks along the bank of the pond all contribute to this softening process. Think in terms of basic shapes.

Add a Top Spill over Drain in the Design

Unless you live in a parched, arid climate, it is inevitable that your pond will overflow. Yet even in dry areas, this can happen when you are filling with the hose and let the time slip away. Rather than having the pond spill over and race toward your house foundation, create a predictable spill over point so that water can go to a safe spot.

Avoid Tall, Vertical Garden Pond Walls

The more vertical and taller the walls of the garden pond, the harder the job you will have when you apply stone to the pond. Loose, natural stones are difficult to stack vertically. Not only does the rock have a tendency to fall, but a greater amount of rocks or larger rocks are also needed to cover this area. Small rocks are less expensive but hard to stack. Large rocks cover vertical spaces easier but are costly and difficult to move. Try to keep the garden pond banks at a 45-degree angle or less, if possible.

Install a Permanent External Water Filter and Skimmer

Unless you make provisions for a permanent water filter mounted in your pond’s wall, your only options for filtration will be manual skimming or floating filtration devices. Hand skimming is a constant job while floating filters take up a lot of water surface and are unsightly. A permanent water filter mounted on the side of the pond stays out of the way. Since it is automatic, it will turn on at set intervals. While a permanent filter is more difficult and costly to install at first, it makes for easier pond maintenance over the long term.

Terrace the Pond Bottom

Sloped garden pond banks, if angled sharply enough, result in sliding rock at the bottom and sides of the pond. Instead, terrace the garden pond’s sides and bottom, much like farming terraces or stair risers and treads. Keep each terrace riser no more than about 6 inches high to avoid stacking rocks too high. Create terraces by cutting them directly in the dirt with the shovel, as long as the dirt is packed tight enough to hold shape.

Plan in Advance for Covering the Pond Liner

Every single square inch of pond liner must be covered up. Even the best, most expensive pond liner is subject to the sun’s punishing UV rays and will break down. The way to protect against deterioration is by covering up all of the liner with something permanent, like rocks up the sides, river pebbles, or smooth gravel on the bottom. It’s better to think ahead about how you want to cover up the liner. Doing so in hindsight often means overloading the pond liner. For example, if you keep the pond terraces low enough, you can use smaller rocks. High terraces demand larger, more visually intrusive fill items.

By Lee Wallender