So You’d Like to Build a Pond?
I apologize for the length of this article but I had a choice to put it onto one page or split it up. I dislike multiple pages myself so here it is on one page.
Do them in the order listed (hint: it is a really good idea to read them all first) and watch out for the special tips scattered through the instructions.
I’ve built a bunch of ponds in my gardening life – some great and some – well, not so great. I wish I had this list before I built that really, really, bad first pond (I covered it in after only one season it was so bad). Now, with this list and the professional supplies that are on the market, anybody can easily build a pond.
Step One: Locate the Pond Area
Locate your pond area and mark out the shape of your pond. This sounds basic but it is surprising the number of gardeners (mostly guys I note)who just start digging without a firm plan in place.
You can use a garden hose to lay out the shape as a hose makes great bends and conforms to your imagination. After you’ve made the shape, I’d recommend you lime or spray paint the edge of your proposed pond and let it sit for a day or three.
Keep looking at the shape and see if it fits into the other shapes in your garden.
Pond layout in white paint and filter set into place
Is it big enough? (not likely – most homeowners build a pond way too small the first time around.)
Is it under trees? (Falling leaves are a pain to clean and the trees block the sunlight so the plants don’t thrive.)
Wet or Damp Areas Are NOT the Best
Most people think a wet area of the lawn is a good place to build a pond. But understand that a wet area might be good for a natural bottomed pond, it is not great for a liner pond as the water will seep under the liner and lift it.
Winter damage can be high in a lined pond situated in a wet zone. While there are solutions for this, they involve special valves and messing about with cutting and gluing liners. It is far easier to avoid the wet zones.
You can build a pond on slopes but do make sure you have enough soil depth to make your pond both deep enough (18 inches) and level.
If you have multiple ponds on a slope, the lower of the two has to be the larger if you want the water to flow properly from top to bottom.
Step Two: Electrical Work
The second step in our project to build a water garden is to arrange for all electrical and water services to be installed.
It is far easier to have an electrician put in the electrical system at the beginning and then you build a water garden that fits the electrical location than to have to pay an electrician to run wires to fit your pond. Similarly, if there’s any plumbing to be done, get it done right now to ease the chore of filling and maintaining water levels. Put those systems as close together as possible.
Pond Safety First!
GFI switches are mandatory in outdoor electrical systems or any electrical circuit having any kind of closeness to water. This switch senses water and immediately shuts itself off. Trust me, this is a good idea; water and electricity do not mix.
Automatic water filling switches are also a great idea is our build a water garden project. They fill up the pond automatically keeping all systems working at peak efficiency. This means you don’t have to stand there with a hose or let it run to overflowing (and you will because you’ll forget to turn it off) when you’ve gone -just for a minute- to do another chore.
Step Three: Biological Filter
Install the water entrance system or biologic filter. Biological filter articles, both homemade and store-bought can be found under the pond supplies area
Step Four: Organic Matter Filter
Install the water exit system or organic matter filter. Again, there will be an entire page dedicated to these filters in the near future.
It is enough to say at this point that these filters have to be level and installed at the correct pond level (yes, there’s a diagramme in the works) so water will flow properly between them when you get to installing the liner.
Step Five: Building A Water Garden – Plumbing
Lay all the plumbing to connect the entrance and exit systems. Remember that our build a water garden project, we have to have water flowing out the exit and then recirculate it back to the entrance filter. Both of these filters are important and plumbing should be fully winter hardy and professional grade.
Important Tip: If you try to “save” on cheap plumbing to connect your filters, you’ll find yourself digging them up in a year or two as winter freezes and thaws and cracks them up. Use professional grade spa-grade piping here or be prepared to redo your pond plumbing. Do not be penny-wise and pound-foolish.
Step Six: Hook up your systems
Now is the time in step four to hook all the systems up to water and power. Get this done now before you go any further with liners and landscaping in our build a water garden project.
Step Seven:Digging the Hole
Step Seven in building a pond is when we finally get around to digging the hole. There is more to digging the hole than buying a nice shiny shovel (although putting a sharp edge on an old shovel makes digging a lot easier).
We want to dig shelves so our shallow water plants have a place to set down roots without drowning. As a design tip, let me suggest you vary the width of these shelves from eight to eighteen inches. This adds some interest to the water’s edge and prevents the pond from looking like a mad cookie cutter dug it out. The depth of this shelf will be approximately six inches below your ground or water level.
Excavate Fish Hiding Holes
We also want to excavate fish hiding holes at this time. If you dig trenches into the bottom as you are building the pond, the liner will sink down into the trench. You can then put a large flat rock over top of the trench allowing fish to have a hole to hide in should predators learn how to swim.
Dig Holes for Plants
We also want to excavate half-bushel basket sized holes in the bottom of the pond for our lilies. If you do not excavate holes (remember the liner will sink into them) then you’ll have to grow your lilies in large plastic tubs.
Planting holes simply make the pond look more realistic. Each lily will require approximately ten to fifteen square feet of pond space in northern climates and slightly larger areas in warmer and longer-growing areas.
Step Seven: Installing the Liner
Now we’re getting to the part everybody looks forward to in building a pond. We’re going to install the liner. (If you want a quick check on evaluating pond liners, click here
But before we install the liner, we definitely want to install an underlay to protect our expensive bit of liner from sharp objects. Some folks use old carpet or newspapers to do the trick and it is true, these will last for a long time and give good service.
Newspapers are a pain to lay down as they constantly move around in the breeze and slip and slide as you’re trying to lay down the liner. Large chunks of carpet are better in this regard but are difficult to get flat. Given the choice of newspapers or carpet, I’d go with carpet.
However, if you’re looking for a professional job, use professional grade underlay. It isn’t expensive compared to the liner and it goes down easily and neatly to protect the liner.
After the liner is down, building a pond really starts to take shape because we’re going to lay down our liner.
I will tell you that you have to bury the edges of the liner at the pond edge to protect it from UltraViolet light degradation so a shallow trench has to be dug around the perimeter of the pond to accomplish this.
Do Not Cut the Liner
DO NOT CUT THE LINER It is really easy to bury extra liner. It is really, really difficult to make a liner bigger once you have cut it. Professional pond installers rarely cut liners when building a pond (they bury the excess instead) or if they do, it is the absolutely last thing they do after all the water is in the pond, the filters and pumps all work, and the landscaping is almost done.
Step Eight: Hook Up the Systems
Step Eight in building a water garden is to hook up the water exit and water entrance systems to the pond liner. Be very careful in cutting the liner to the exact dimensions of the filters and be very liberal in your use of pond caulking.
Tight, snug fit
Pond Caulking is Important
Pond caulking is another example of never using cheap imitations. You can purchase cheap caulking but proper professional caulking will survive winter ice and summer sun. Cheaper caulking deteriorates outdoors and then your pond leaks. Leaking ponds are a royal pain and saving a few bucks simply isn’t worth the future hassle. Mind you, gardeners do it all the time so what can I say – it is their problem in a year or three.
Step Nine: Adding Rocks
Step Nine is to add rocks to the pond. Start by laying a single rock in the middle of the pond and then put a circle of other rocks around this central rock. The circle will not be even (that’s OK) and there will be spaces between the rocks (that’s OK too). Add a second and third circle of rocks so that the bottom of the water garden is slowly becoming rock-filled. Continue adding rocks in circles around the pond until the entire bottom and sides of the pond are filled with large rocks.
Stack ’em So They Don’t Fall
Sidewalls will take a little creativity as you learn how to stack the rocks in such as way that they will not immediately crash or fall over.
Slightly larger rocks belong at the bottom of the wall and progressively smaller rocks go towards the top of the wall. The objective of the sidewalls is to create a natural looking wall and this is your first crack at artistic rockwork in building a water garden.
Once the large rocks are all added by hand ( do not dump them in with a wheelbarrow or mechanized loader – you run the risk of puncturing the liner) you can now add smaller rocks to fill in the spaces. These can be added by wheelbarrow as the larger rocks should be covering the entire liner with no liner showing. The smaller rocks are sized to fill in the spaces and should be added by hand or shovel to fit neatly into the spaces left by the larger boulders.
Step Ten:: Lighting System
Now is the time to install the lighting systems.
Wires are never cut short but buried and several feet of wiring is left at the end of each underwater fixture.
Note that if you don’t leave yourself this extra wire, you’ll
eventually wind up changing lightbulbs under water or draining the pond to install new bulbs. With the longer wire, you can lift the fixture from the wire and change bulbs easily.
Laying the lighting cable now is easy as the pond has not been filled with water and there is lots of loose gravel for covering over runs of wire.
Step Eleven: Adding Gravel
Add gravel to our liner.
We finally use wheelbarrows here to dump the gravel into the pond but we are extremely careful about using shovels to move the gravel around.
We do not want to disturb our larger rocks or puncture the liner.
The backs of rakes are used to smooth the gravel in place unless you’re feeling brave or professionally competent and then the tines can be used.
In other words, use the racks with the pointed tines pointed straight up and not down towards the liner.
Adding Water to the Pond
We finally get to add the water in our efforts. Turn on a hose and start washing off the gravel with a jet of water. We want to collect all the dirt from the gravel into the centre of the pond so start cleaning and filling (at the same time) from the centre and work towards the edges.
Use the strongest jet you can and clean the gravel as best you can. It will all be removed in the next few steps as the water is all roiled up and the filters are working.
Step Twelve: Build the Waterfalls
If you are building a waterfall, this is the time to get it working right.
Step Thirteen: Waterfall Checking
Now is a good time to ensure the waterfall is working properly, and repair any leaks or back-flows.
In other words, you built it in the previous step but now it’s time to turn it on and check it before you go any further.
Take great care to make sure the waterfalls are working and *not* losing any water either behind them or out the sides with splashing.
Note Building a waterfall is another separate project with its own set of challenges. It is not covered in this note.
Step Fourteen: Install the Water Plants
With everything working, our next step is to install our water plants.
See the pages on water plants and water lilies for specific information on how to plant each of these types of plants.
Step Fifteen: Landscaping
Finish off the outside edges of the pond with landscaping.
Now that you have your water in the pond, the waterfalls are falling and the streams are streaming, it is time to get those water-side plants into the ground.
Step Sixteen: Add Fish and Oxygenating Plants
This is one of the fun steps. Add the fish and oxygenating plants
We’re getting quite close to the end of the process, Only a few more steps to go.
Step Seventeen: Bury the Liner Edges
Bury the edges of the liner in the soil around the pond.
If you really want to, you can cut the liner now but you never know what changes you’ll make in the future or where you’ll want to bring your second pond to meet the first (don’t say -never- I know way too many gardeners that said -never- and ended up saying -certainly- to a new and expanded pond).
Step Eighteen: Mulch the Pond
Mulch the garden around the pond. Blend your mulch to the pond stony edge to ease the transition
Step Nineteen: Add Bacteria
Add bacteria as desired.
Step Twenty: Clean ‘er Up – You’re Done
And finally, clean up the project area putting all tools away and the various odds and sods back into the tool room and/or garden shed.
Now, enjoy yourself and congratulate yourself on a job well done.
Here are other practical articles on building and maintaining backyard ponds