Pond Building 101 (Part two)
By Ray Jordan
Martha
& I have just finished two new ponds. We
knew we wanted our main pond to be a “ high tech” koi pond and the second to
be a small simple goldfish/watergarden pond. We decided to use a pond contractor
to do most of the actual work but designed and supervised the entire operation.
We learned a lot along the way.
In this article I want to get you to think about some of
the options and decisions you will need to make as you start designing your new
pond. Also, I want to reemphasize that you should
not leave the design up to a contractor. The one exception might be where
you have found that “perfect” pond, for your needs, previously built by a
contractor. However be sure to
thoroughly quiz the current pond owners about what they wish they had done
differently building their pond and benefit from their experience. I am not
going to try to discuss the actual construction of a pond. Actually, I have
found out the construction is the easy part. It is the design of the pond and
the filter system that are the most critical. There are books and videos in our
club library that cover in great detail how to build almost any type of pond. My
goal is to get you thinking about what type of pond you want and then get you to
start putting the actual design on paper.
The
big decisions
The big
decisions will determine what type of pond you will be building. You should
design your new pond and filter system to be easy to maintain. The extra cost
and work involved in trying to retrofit a new filter system or rebuilding a pond
costs far more than designing it correctly to start with.
We built a new pond to replace our old concrete pond that was constructed poorly. The waterfall separated from the pond created a crack that leaked progressively more water until we had to do something. So please be sure that your pond is designed and constructed properly.
1) Your budget is a prime consideration. Do not forget to include everything you will need to complete the project. I have included an example to help you develop a budget. This is only a crude estimate and the final cost will vary depending on whether you do some of the work yourself. Also liner ponds are quite a bit less expensive than concrete ponds. Liner ponds are a much easier do it yourself project than concrete ponds. The items in bold print are the basics for a koi/watergarden pond. The items listed in Italics are the extras that make your pond more special. Low end assumes a “do it yourself project” (DIY) and materials only. High end assumes large pond with most work done by contractor. I hesitated to put any type of cost information into this article. Cost will of course vary greatly depending on many factors
Use the following information as a starting point only. You will of course want to get bids and references from several pond/pool contractors if you decide to have the work done for you.
Low End(DIY) High End
Excavation
$0
$5,000+
Plumbing
$50
$2,000+
Vessel
$250*
$8,000+**
Pump/s
$100
$1,000+
Filter/s
$100
$3,000+
Waterfall
$100
$1,000+
Basics
$600
$20,000+
*
small liner pond
** Large concrete pond
Skimmer
$100
$400+
UV Unit
$250
$1,000+
Landscaping
$100
$2,000+
Decking/Walks
$500
$2,000+
Electrical
$50
$1,000+
Lighting
$50
$1,000+
Other
$
$
Extras $1,050
$7,400+
Totals
$1,650 $27,400+
That is a pretty big range. I would advise you to plan on some surprises during construction and be prepared to spend at much as 20% to 30% more than originally budgeted.
2) You will be tempted to go for the “in between” type of pond I described in last month’s article. After all wouldn’t it be great to have a single pond that worked well as both a water garden and a koi pond. I urge you to decide where your greatest interest lies and go that direction. Of course your spouse will want a water garden and you will want a koi pond. My advice would be to build a “proper” water garden now and save a big spot in your yard for that koi pond later. Now is the time to design in your options for future projects. Make sure your plumbing or filter layout will not have to be moved or rerouted as you add future projects. Also a water garden will be an easier project for a first pond and the experience you gain will help you when you build a koi pond later. However if koi is your thing then you will want to build a proper koi pond right now.
Water gardens need a lot of direct sunlight so locate them properly. Also decide where you are going to place your filter system for a larger pond. Finally, build as large a pond as your budget and space will accommodate. If you are building a koi pond be sure to design a average depth of at least three feet and if possible go up to five to six feet of average depth. After all, in the same footprint a pond twice as deep holds twice the water capacity, which is a critical factor in giving your koi the best possible water quality and growing room. Depth also gives you fish more exercise room and minimizes the abrupt changes in temperature we experience in Texas.
3) Decide what materials you will be using to build your pond. Your main choices are a rubber/plastic liner, cement block, or concrete/gunnite construction. There are also commercially available fiberglass and precast plastic ponds. Ready made ponds cost more than liners. You simply dig a hole for the preformed pond. Set the pond in place hook up the plumbing and filter system and back fill with soil or sand. One drawback to this type of pond is it’s tendency to float out of the ground and break the plumbing connections if not placed in a well drained area and kept full of water.
Liner ponds have a lot of appeal because of their ease of installation, relative low cost, and unlimited size potential. You dig your hole the size, depth, and shape you desire. Install your plumbing and buy a single piece of liner significantly larger than the area of your excavation. Remember you will need your liner wide and long enough not just to cover the bottom of your pond but also the sides and extend at least two or three feet beyond the hole. Also be sure to include the amount of liner needed to extend under your waterfall. Buy a single piece of liner in order to minimize the chance of leaks. There are several types of material used in liners. The stronger and thicker liners last longer and are more puncture resistant. However they are also much stiffer and more difficult to mold into an irregular shaped pond. Special bottom drains and other pond fittings are available to connect the plumbing as needed. Be sure to cushion liners from sharp objects under the bottom and walls. Most liner ponds use old carpeting and sand to be sure sharp objects are kept away from the liner.
After the liner is placed into the hole and the plumbing fittings are connected you will begin to slowly fill the pond with water. As the liner fills the water pressure will force the liner into the shape of your excavation. Keep adjusting the liner to minimize the folds that will develop. Try to help the folds to flatten against the sides of the pond to minimize the places that silt and other waste will collect. You will want to protect your liner from direct sunlight. Most liner pond excavations have a shallow lip as part of their design to allow the liner to lie under/behind the edging material around the ponds lip.
This technique keeps the liners edge out of sight and also protected from direct sunlight. You can use lumber as a backboard for your ponds edging or you can pour a concrete collar. Make sure your pond’s top edge is several inches higher than the surrounding yard. Be careful that runoff in a heavy rain cannot get into your pond.
Another option is to use concrete or gunnite instead of a
liner. Be aware you will also need to use ½ in. rebar reinforcement to keep
your pond’s shell from cracking. Concrete should be a minimum of twelve inches
thick for the floor and have nine-inch walls. You can subcontract the steelwork
and the concrete work separately. Gunnite
is a type of concrete and a specific method of application that uses a large
pumper truck to “blow” the material on under high pressure that creates a
much stronger shell than traditional concrete. However gunnite has a very rough
texture and will need a plaster coating to make it smooth and also to waterproof
the shell. If you use concrete you will want to request a special “pool” mix
that makes the concrete waterproof. I recommend you use a pool/pond contractor
if you want a concrete/gunnite shell.
Another option would be to pour a concrete/rebar reinforced
floor twelve inches thick and then build the walls with cement blocks. Cement
blocks have cavities than allow you to insert steel rebar reinforcement and fill
with concrete which makes it almost as strong as regular poured concrete. You
would need to plaster the entire pond or use some other type of waterproof
coating such as fiberglass or rubber. The advantages of concrete/gunnite are
longer life, more professional appearance, can be any shape and can use larger
pipes on pond. The advantages of a liner pond are less expensive, easier do it
yourself, and liner does not affect water chemistry.
CONSIDERATIONS
FOR A KOI POND
A koi pond’s shell needs to have a smooth finish that will not scrape or cut your fish. Only use rock that is smooth and rounded. It is important not to have crannies where your fish can get trapped. I lost several fish in my original koi pond because rocks jutted over the pond. Several of my fish jumped against sharp rocks and cut themselves which sometimes resulted in an ugly scar or occasionally led to a more serious infection that killed some fish. I also had fish that wedged themselves between rocks and became trapped.
Because of the large amount of waste that koi produce you need to plan an efficient filter system. If you build a koi pond the first decision you should make is what type/size of filter system are you going to use. The best systems use a settling tank to help remove most of the solid wastes before they can clog your biological filter. Large ponds require large filters. You will also want an air pump to supply aeration to support the koi and the beneficial bacteria in the bio filter. You can spend $5-$20 for smaller pond quality fish up to hundreds or even thousands of dollars for larger show quality koi.
In summary the ideal koi pond would look like a swimming pool but would have a larger filter system. In fact swimming pools can be successfully converted into koi ponds.
CONSIDERATIONS
FOR A WATER GARDEN
A water
garden is intended to create an environment that enhances the growth of water
plants. Water Lilies and most other blooming water plants require direct
sunlight for most of the day to insure optimum blooming and growth. Most water
plants need to be pruned, fertilized, and repotted regularly during the growing
season. This means being able to get in the pond easily. This is one reason most
water gardens are fairly shallow from 18 inches to 30 inches in depth. Decide
which water plants you want to grow and design your water garden with the proper
depth for those plants. Many water gardens are designed with a shallow shelf for
their bog plants with a deeper area for the water lilies and related plants.
Most water plants do not like water splashing on their leaves so keep your best
plants away from a splashing waterfall or fountain.
Water gardens should look like a natural pond. Water gardens usually have water features such as waterfalls to add interest. Because the emphasis is on plants there is less need for an elaborate or large filter system. You will still want a small filter system to maintain clear and clean water.
Water plants can be inexpensive or pricey depending on variety. However, water plants grow quickly and multiply like crazy. In no time you will be looking for someone to swap or trade plants with. The variety of plants available is amazing with Tropical and Hardy lilies, lotus, including day and night bloomers. You will have lots of options to make your water garden unique and special. Water lily blooms are prolific during the warmer months and make wonderful flower arrangements.
Goldfish are a better choice than koi in a water garden. Goldfish are smaller and require less filtration. They are less likely to root around in your potting soil and are popular and very beautiful. A fancy show quality goldfish can be pricey but pond quality goldfish are inexpensive.
SUmmary
The best type of pond for you depends on your interests, budget, available space, and needs. The more you know about what you want to accomplish with a pond the better you can decide the best design to build. Some of our non-pond friends think we are crazy to have spent the time and money on our new ponds. However, these same friends drive pricey cars, eat in restaurants almost every night and/or have other expensive hobbies and toys. When you think about a well-built pond lasting twenty years or more the cost per month does not seem so much.
You will need to do some research but, at some point it is time to get started. I promise that the extra planning will be well worth it. So when are you going to get started on your new pond? The sooner you start the sooner you get to enjoy your new pond.
Happy Pondering