More Pond Designs
Puddling with Concrete
>Safe Ponds for Children
A number of water gardeners have written me to ask if there is any way of constructing an attractive pond around which toddling children can play in safety. Happily, there are a couple of types which I can recommend.
THE RAISED POND
One of them is the raised pond. This pond is constructed like the sunken reinforced concrete pond, with two modifications. A complete set of inside and outside wall forms are required to shape the concrete shell, and the foundation of cinders or stone for it is made a few inches thicker and tamped with special vigor to give the pond a solid footing.
Such ponds can rest entirely on top of the ground, or they may be sunk part way.
You may recall that I told you that water-lilies planted in a tub or similar container and left above ground will not bloom. This does not apply to raised ponds larger than a card table. The water mass in ponds this big or bigger is enough to insure a constant temperature. Fish and water-lilies do as well in large raise ponds as they do anywhere else.
THE HIDDEN SCREEN
A device which can be quickly fashioned and made to fit into any pond of regular shape provides even more safety. With three-quarter-inch pipe, construct a frame which will fit as a snug rim around the inside of the pond. Cover this framework with strong wire fencing, 4-or 5-inch mesh. Screw hooks or brackets into the pond walls to hold the framework in place 3 to 4 inches below the water line (as shown in Drawing 20). If you have not built your pond yet, it is easy to provide a holding ledge for a safety frame by embedding bricks in the walls so that they extend an inch or two.
Water-lilies and aquatics grow freely through the fencing. Goldfish do not seem to notice it at all. The fencing cannot be seen from any point except directly above the pond. And, best of all, a child tumbling into the pond tumbles into only a few inches of water.
If your toddlers are particularly rambunctious and you want to play doubly safe, build the raised pond with the protective framework in it. Many water gardeners do this.
The Summer Pond
The quickest and cheapest pond that can be made of concrete is one called the summer pond. The earth into which it is built must be firm enough to hold the shape of a deep trench cut into it.
Stake out the dimensions of the pond, and then dig a narrow trench around the perimeter. The walls of this trench will serve as forms for the concrete. A 30-inch excavation for the walls is best. Eight inches is about as narrow as you can dig the trench, so the pond walls will be 8 inches thick.
Fill the trench to a depth of 6 to 8 inches with whatever stones, broken bricks, old iron, and other rubble you can find, reinforcing with the iron as efficiently as possible. Fill the voids of this rubble with a 1-2-3 mixture of concrete, tamping it vigorously to work out any air pockets. Add another layer of rubble and fill again with concrete, and repeat the process until the wall forms are filled.
After the walls have set three or four days, remove the earth from the center of the shell, going down to a depth of 30 inches. Cover the bottom of the excavation with a 6-inch layer of rubble, and work into it the same mixture of concrete you used in the walls.
Keep the pond covered and damp for ten days. Then coat the inside of it either with a waterproofing layer of pure cement mixed with water or with asphalt. Cure the pond to neutralize tile alkalinity of the new concrete, if the concrete is exposed, and plant your water garden. (See Chapter 13 for other waterproofing methods.)
If you live where winter does not cause much frost upheaval in the ground, you may be able to maintain a pond of this sort without much trouble. Chances are, though, that the pond will require at least a new coat of waterproofing cement or asphalt every spring. Even if the pond is drained for the winter, a few cracks are almost certain to develop.