Before a shovel ever hits the ground we decided our pond would be a passive system without pumps or fake water falls. Another important decision that was made when we were planning this project was to situate the pond such that it would help slow and block the flow of water towards the house. It also catches rainwater, so if it is not entirely full, the pond will act as a buffer reducing the total volume of water pushing its way into our foundation. We also wanted the pond to be viewable from every window on the back of the house. These are some examples of the considerations that may need to be evaluated before planning a pond for your system.
- - -
Installation
After you figure out the dimensions and location for the pond, the first thing to do is to outline the shape you have decided upon in spray paint or flour. We decided upon a kidney-bean shape with the concave side facing the uphill side to block surface water. Then, with shovel in hand, dig out the sod along the outline, that way you are giving yourself a buffer to do more reckless digging in the center without having to worry about messing up the shape.
With the outline etched into the ground, continue to remove shovel sized chunks of grass and soil from within the shape. This is the hardest part, though not the most nerve-racking. I didn’t have a good idea of what to do with the dirt when I got to this point so I piled it up next to the excavation site. This made extra work for me and Andrea by forcing us to deal with the material twice.
The picture to the left has a few things going on in it. First of all, the deeper sections (18-26″) were outlined, leaving a 1 foot ledge before the drop to deeper waters and a shallow (12″) end. In it, the installer is beginning to dig out the deeper sections. The other piece that is important to notice is the hill of soil snaking along the outside of the pond in addition to the metal stud in the background. While you are digging the pond you should be using the removed material to level the surrounding ground. This is done so that when the liner is placed in the hole and the whole thing is filled, the water comes up to the same level all the way around the pool. Use the stud to span the gap from one end to the other and check it with a level on top, adding soil as needed to bring the whole perimeter up to level.
The next step was to add a layer of padding in the form of fine playground sand to protect the liner from rocks or roots. Do your best to remove as much large debris from the pond walls and bottom but the sand really smooths it all out.
After unfolding the liner and stretching it out over the pond, get in the pond, smoothing out wrinkles as it fills up with water. When I was doing this I slipped, soaking myself, so please be very careful. While the pond is filling up, use several bigger rocks to hold the liner as you adjust it and try to smooth it out as well as you can. After the pond is full pour in store bought dechlorinator specifically for ponds. Then drive around to several small ponds and creeks and get samples of water to put in your new pond. The hope is that the biological systems (algae, fungus, bacteria, protozoa…) would transfer to the pond, stabilizing the the system.
In the picture to the right you can see our pond immediately after it was finished. I went to Panther Hollow Lake and got a few scoops of duckweed which you can see floating in it. The duckweed should be handy in removing excess nutrients and if it gets to thick, I will just scoop it out and toss it in the compost. I used the soil in the background to help re-grade around the foundation of the house, which had been sloping the wrong way.
A pond like this provides a beautiful spot to sit and enjoy whatever may happen as well as diversifying the ecological possibilities of our yard. You now have a small water ecosystem with multiple depths that has a border of its own creating unique conditions for a variety of plants and animals.
- - -
Anchored Floating Plants
- Water Lily - Nymphaea - A garden pond classic, provides shade to limit algae growth, a place for frogs and insects to rest, a shady spot to hide for the fish, and beautiful summer flowers
Emergent Plants
- Blue Flag Iris - Iris virginica shrevei- Sits in the shallows, this iris provides a nice upright feel to the pond and has beautiful blueish purple flowers for people and insects to enjoy
Floating Plants
- Duckweed- Lemna minor - A wonderful, fast growing floater, it grows quickly to cover the pond’s surface and helps reduce nitrates in the water, limiting the threat of an algae take-over, and if it becomes too thick it can be scooped out and thrown into the compost heap or straight onto the gardens
- Water Hyacinth - Eichornia crassipes - A dreaded invasive in subtropical and tropical regions but here we can enjoy their beauty without fear; it is one of the fastest growing plants in the world, freely dividing to fill the pond, it provides shelter for insects and fish, the entire plant can be eaten, its fine root system cleans and oxygenates the water, they shade the depths and pull out excess nitrates; these too can be thrown into the compost heap if they are taking over
Submerged Plants
- Anacharis - Egeria densa - Can grow free floating or anchored by roots in the substrate, helps to control nutrient levels, adds oxygen to the water, serves as competition to algae and provides shelter for insects and fish
- Hornwort - Ceratophyllum demursum- “Also known as Coontail, has sturdy, layered hair-like foliage that helps oxygenate and clarify the water as well as keep algae growth to a minimum. It is found free-floating worldwide, in moving and still waters, or loosely anchored in muddy bottoms.” (www.liveaquaria.com)
- - -
Animals
- Comet Goldfish - Carassius auratus - A common goldfish variety, will eat debris and insect larvae, grows to be up to 12″ long and can overwinter in the pond without supplemental heat
- The Hitchhiker - An unknown variety of fish, we think came in on some of the plants that were mail-ordered, could possibly be a mosquito fish of one type or another, but we are glad to have him