Legally build your own predator-free, 3 foot deep “Fence-less Koi Pond”TM in your front yard.
Most cities have building codes or ordinances prohibiting the construction of ponds or fountains deeper than 18 inches in a front yard without the protection of a 6 foot perimeter fence. Many have the same restrictions for a side or back yard.
The obvious reason is to protect against accidental drowning. However, a shallow pond makes it impossible to have koi fish or turtles, since both of the aquatic creatures require at least three feet of water to prevent becoming lunch for raccoons, cranes, egrets, trolls and gnomes. These evil-doers can easily wade in 18 inch of water, but can’t in 3 feet of water; plus you can create caves for them to hide in. Turtles will generally not stay in a pond if they do not feel safe while basking in the sun, which all turtles require. They don’t feel safe while exposed on the shore so they look for a log, lilies, protruding rocks or islands of any sort. That way, in the event of danger they can retreat to the deep water and caves in any direction.
With this new engineered design I came up with in 1984, it solves every problem. You can legally skirt the building code for depth requirement, the koi will be safe from predators and the turtles will be safe, too — and tickled pink! All right already, I’m getting to it!
The good news for you liner guys — this design works with liner construction however be aware the is a very strong possibility of an eventual cave-in from the weight of the grid covered with rocks. You should make the support ledges a minimum of 12 inches to better support and distribute the weight
Now for you “professionals” LOL that use reinforced concrete (used in the construction of the Hoover Dam) — compared to liners, it is basically permanent and will be enjoyed by the great great great grandchildren. These directions will address rebar and concrete construction. Best thing is, any do it yourselfer can work with 3/8 rebar and concrete.
I will cover the general design and functionality of a “Fence-less Koi Pond”TM but not technique.
First decide the length, width and depth of the pond. Since it is reinforced concrete, unlike liner construction, it can be as deep as you desire! The width is the critical measurement, since you will be spanning the pond with 1/2 inch epoxy-coated rebar with width and length grid, then placing rock on the grid. If it is over a 5 foot span, you will need a 4-6 inch column to offer support in the center. Create a 4 inch ledge 18 inches down from the edge of the pond to support the rebar grid. As you have now realized, once the pond is filled, and rock 9 inches or larger are placed on the grid, leaving every third grid open for escaping fish, turtles or frogs, you now have a legal 18 inch deep pond.
You will incorporate two 8 inch anti-vortex suction drains (the same drains used in a swimming pool) in the floor of the pond, Dual anti-vortex drains never plug and will never suck up a fish, frog or turtle, only suspended particulate like fish doodoo. Consequently, you will rarely have a need to access the lower pond. The skimmer and AquaFill water leveler are located above the grid and easily accessed. Install the quietest, most energy efficient centrifugal pump on the market, e.g. a Sequence pump (3 year warranty). Use an Aqua Ultraviolet Ultima II bio-filter with a ultraviolet light for algae and pathogen control.
The epoxy-coated grid
- makes the pond legal
- protects pond life from predators
- provides a platform and support for a turtle island
- provides a place for potted water plants of every variety- from papyrus and cattails to water iris and lilies, sweet flag, taro, pickerel, parrot feather etc.
This is the first time 28 years that I have published the design of my “Fence-less Koi Pond”TM. Remember where you heard it first, and pass it on.