How To Build A Pond

How To Build A Pond

When you first start off on your journey to build a backyard water garden pond it can be a bit intimidating.  Don’t be overwhelmed, just take it one step at a time, and before you know it you will be enjoying your own waterfall with the soothing sounds of rushing water right in your own backyard.

backyard water garden koi pond with waterfall

Here are the 3 major steps

  1. Location and Layout
  2. Rocking in your pond
  3. Adding the finishing touches

There are many ways to approach this and this and it all depends on the size and scope of what you want to do. If space is an issue then a typical waterfall pond setup may not be suitable. You can check out our article on the pondless waterfall. Don’t let your circumstances stop you. There is a water garden out there suited for every situation.

We are going to be building a typical pond with a waterfall setup using a skimmer box and waterfall unit. Using a pond kit is the most convenient way to be sure you have everything you need for your project.

Before You Begin

start building a pond remove grass

I did some prep work while I was still in the dreaming phase. A lot of my time was spent in the dreaming phase so I already had a rough idea as to where I wanted my pond. When I was doing a previous project, I had an outlet installed nearby to power the future pond pump, lights or aerators. The waterfall pump I used came with a 25’ cord on it, so as long as there is power within that distance, you will be all set. Just be sure the outlet is GFCI protected and you follow the electric codes for your area.

When you set out to bring your vision to life, change the dimensions to whatever suits you. What I used, fit my space and may differ from what you may be trying to accomplish. You can follow this exactly, or put your own spin on it. Either way, something amazing will come out of it! This pond isn’t going to build itself, so let’s get started!

Pond Location & Layout

So, these first few steps aren’t just about building a backyard water garden, but also WHERE to build one. This is an important step that shouldn’t be overlooked. Remember that choosing a location so your garden can be viewed in all four seasons is important to maximize your enjoyment. Your chosen location will allow you to enjoy it during the winter months as well as on a rainy day.

Take a ride to your local pond supply store for ideas and inspiration. When I did this my head was spinning with ideas. The possibilities are truly endless.

A view from your dining room, kitchen or living room is ideal. I see many people opt to put their ponds in their front yard. If that’s where it needs to go so you have maximum viewing time throughout the year, so be it.

One word of advice, before you even get out your shovel, be sure there are no underground utilities on your site.

Ok, you’ve chosen your location and are completely satisfied with it. Now it’s time to lay out the shape you envision. Location and layout go hand in hand. Sometimes the location will dictate the shape, where some locations are a blank slate, like in my case.

Either way, use a garden hose or extension cord and place it in the shape that you want your pond. Take your time with this step. After you have done this, step back and look at it from various locations, inside and outside of your home. I suggest you leave it for a day or so and see if it suits you. You want to be sure because moving location is difficult once you get started.

Sizing Your Pond

Don’t be afraid of going too big. This is the one regret people have once they have their pond built. A 10′ x 15′ size seems huge, but when you measure it out in your space outside it may not feel as large.

The best advice I’ve heard is get the largest pond you can afford and will fit in your space. If space is a problem there is no shortage of small garden pond ideas out there.

Once you’ve decided “this is it” take a can of spray paint and go around the perimeter moving the hose or cord out of the way as you go. This will give you an even clearer picture of what you are about to do. The next step is to get your flat edged shovel, and chop around the entire perimeter.

This will create an edge for removing the grass if you have any. Then scrape off all the grass, about an inch deep. The sod you take out does not make for good backfill, because it will settle quite a bit as the grass decomposes.

Another thing to consider is the placement of your water feature and skimmer box. These should be located at opposite ends of the pond to ensure proper water circulation. Again, use a garbage can or something to represent the waterfall unit, and step back to see if it fits your vision.

You have made most of the tough decisions, the size, shape and location are taken care of. Time to order all the supplies you will need.

Order Your Pond Supplies

Before you order your pond supplies there are a few decisions you will need to make. The first decision is the size and depth of your pond. This will determine how big of a pond liner you will need.  When you get your pond liner you will also need underlayment to protect the liner from sharp sticks and rocks. Your pond liner and underlayment should be the same size.

You want to order your supplies now before you start digging so you can put your waterfall and skimmer box in place. It helps to have things where they will go. Also, as you dig the pond, you will use the dirt to backfill around the waterfall. I’m not going to go into too much detail about supplies here, just a short list.

The Pond Kit

I found that the best option was to use a pond kit (affiliate link to amazon for the best current price) Find the right size kit for your project and it takes out a lot of the guesswork. All the components are sized right for each other and will work together in harmony when you use a pond kit. That’s what I used to build this project.  

Most pond kits come with everything but the rocks gravel, and flagstone. On a positive note this way you can use the materials that are native to your place in the world, and make your space look more natural.

Here is a list of the most common pond supplies you will need to get started:

large koi pond kit
  • Pond Liner
  • Liner underlayment
  • Waterfall Unit
  • Skimmer box
  • Filter media
  • Submersible pond pump
  • Check valve
  • Return line
  • Beneficial bacteria
  • Lava rocks
  • Waterfall foam
  • Submersible lights (optional)
  • UV light (optional)
  • Rocks and boulders (more than you think you will need)
  • Gravel
  • Flat flagstone

Digging Out Your Pond

Before you begin digging it’s vital to know that there is nothing below.  A simple phone call to 811, or visit will give you piece of mind that you can dig safely. You can be assured you will not run into any setbacks once you start.

call before you dig a pond

Learn from my mistakes. I should have taken my own advice above. I did not call before I started digging. At about 12 inches down I ran into trouble. My shovel hit something. Wouldn’t you know it, there was conduit (plastic tube that protects an electric line) running right through the middle of my pond location! I didn’t let this stop me. I had to dig around it, and then reroute it. It took some time, and it was a minor setback. Remember, “nothing worthwhile is easy”! Another of my “dad sayings”. OK enough with this tangent, now back to the task at hand.

If you are renting equipment for the digging process you should wait for the pond supplies to arrive before you get started. This will allow you to place your waterfall unit and backfill around it as you dig out your pond.

first level excavated digging a pond

In my case I ordered my materials, and while I was waiting for them to ship I began to dig. Like I said, I am on a tight budget, so that means no heavy equipment rental. All I have is a vision, a shovel, and a will! I wanted a 36-inch drop from where my waterfall spilled out to the surface of my pond. In order to achieve that I had to build up the ground where I placed my waterfall unit. I used 8-inch cinder blocks directly under where my waterfall unit was going to be placed. Two courses of cinder blocks were needed below my waterfall unit to get the height I wanted.

Gravity – It’s the Law

pond waterfall unit installation

Understand that settling will occur no matter what you do, but in order to keep that to a minimum. One key is to not disturb the ground beneath the blocks.  This will minimize settling. I filled the hollow cores of the blocks with dirt and compacted it down. This gave me a level surface, with minimal settling to rest my waterfall unit. Another advantage of using the cinder blocks is the fact I didn’t use dirt I excavated giving me more to work with for backfill around my waterfall unit.

When you begin to dig a pond, you will want dig down in steps or levels. First dig the whole outline down about 12 inches deep. All the while dumping the dirt around where you want your waterfall to go. Compact the dirt as you go. It’s amazing how much settling can occur in a season, so packing it down as you go is very important

Pond Supplies

If you haven’t received your pond supplies yet you will need them before you go any further. I recommend, waiting to place your waterfall unit before digging anymore. You want to be sure you have enough dirt to cover up and gently slope your waterfall mound

trench between pond skimmer box and waterfall unit

Glue and attach all the necessary fittings and your water line to your waterfall unit. Place it in its location. Be sure that the unit is level from side to side. You don’t want the water to rush out of one side and not the other. To make the water flow properly make sure it is slightly pitched forward toward the opening.

Layer Your Pond

Now with the entire shape of your pond dug down to a 12-inch depth it’s time to grab your spray paint once again. Create another shape, about 12 to 18 inches in from the edge. You can either follow the existing shape of the pond, or create a different shape all together. You are creating a 12 to 18-inch shelf for plants to thrive at various depths. This will also help during the rocking process later and when it’s time for seasonal maintenance. These ‘shelves’ will allow you to get in and out of your pond easier.

With your next shelf outlined, and your waterfall in place it’s time to start digging again. Dig this layer down another 12 inches, all the while placing the dirt around your waterfall, compacting it as you go.

Keep It Level

One key thing to keep in mind is that water always finds level. As you dig out your pond, make sure the ground around the pond is level. Use a long straight 2×4 or even an extension ladder with a level on top that spans the width and length of the pond to check for level. In my case the ground had a slight pitch to it, so I had to build up one side as I dug. Keep in mind the water level in your pond can never be higher than your lowest point.

building a pond keeping the edges level

Start digging a trench from the skimmer box location to the waterfall unit next. A trench 12 inches deep will suffice. After you have done this, lay your water line in the trench and make sure it’s long enough. In my case it was 4 feet short. A quick trip to the store fixed that. I added an extension using a rubber boot and pipe clamps.

UV Light In the Filtration System

You can do what you want, this is completely optional. When I initially put my pond in I regretfully opted not to install a UV light.  The very next season I was putting one in. I had to dig up the water line between the skimmer and waterfall unit and place the light in flow of my return line.  Looking back, I would have just put one in right along with my pond installation. Check out our more in-depth article on UV light installation here.

One quick thing to mention, your UV light will be easier to hide if you install it when you build your water garden. It is always more difficult as an afterthought.

Pond Skimmer Box

dig a pond one shelf done and skimmer box dug out

Now would be a good time to place your skimmer box where it will go. Place it on the ground where it will go and trace around it. Now dig out its shape. Your water line will be about a quarter of the way down from the top of your skimmer box opening. Keep this in mind when digging out for your skimmer box.

Do not dig deeper than you need to, try not to disturb the ground below the depth of the box to reduce the amount of settling. Remember, it’s important the skimmer box is placed level front to back and side to side. Don’t backfill around the skimmer box at this time in case you need to fine tune it later.

Final Pond Depth

digging a backyard pond with three levels

Now for the last of the digging. Again, grab your spray paint and trace another outline for your final depth of your pond. Dig this shape out another 12 inches or so, again placing the dirt around your waterfall, and compacting as you go. Look for any sharp stones or roots wherever the liner will be placed.  Doing this will help you avoid problems in the future.

digging a pond by hand three feet deep

You can make this final step as deep as you would like. If you live in a colder climate and plan to have fish, be sure to make your pond deep enough so your koi and goldfish can survive. The size of liner and underlayment you have is the only thing limiting the size of your pond.

Keep in mind, these first few steps are some of the most important. Just like constructing a building, the planning and foundation are vital to the success of the project. The same hold true to building a water garden. Now that you have a giant hole in your space it’s time to fill it back in. The fun begins in the next part. This is where you will truly see your water garden come to life.

how to build a pond dug out by hand ready for pond liner

A Place for Pond Fish

One thing left out in the previous installment of this “how to” guide, was to dig out a place for a fish cave. If you plan on having pond fish in your water garden, it’s a good idea to give them a place to hide from pond predators.

digging a koi pond fish cave during pond installation

This can be accomplished by digging out a small channel.  The liner will form to the shape you made. After your liner goes in, use a large drain pipe or bucket to be the walls of the “cave” then stack rocks around to hide it. Once I start rocking the whole thing in you can see the cave better. Check out the pictures below.

Liner Underlayment

It will be helpful to have a second pair of hands for this next step. Unfold your underlayment all the way beside the pond. Lift the underlayment over the hole (be careful not to fall in) so it’s centered and put it in the hole. Be sure you have even amounts on all sides. The underlayment should be big enough to go 12 inches or so on either side and over your waterfall and skimmer box (on opposite ends of the pond).

Once the underlayment is centered and placed in the hole, step in. Starting at the bottom kick it into place. Start in the middle of the bottom and work your way around the perimeter. Be sure to remove any sticks, stones, or sharp objects you come across. Move up to the next level and do the same. When you finish the underlayment should have taken the shape of your pond.

Pond Liner Installation

This is definitely a two-person job depending on how big your water garden is. The pond liner is much heavier than the underlayment. When dealing with the liner, more care must be taken to ensure it is not damaged during installation. Do the same with the liner as was done with the underlayment. Open it up all the way next to the pond. Gather your friends and lift the liner and center it over the pond. Once it’s lowered in the hole, it needs to be formed to the shape of the pond.

Start in the middle of the bottom and work it so it lays as flat as possible and fully into the corners. I don’t recommend kicking it into the corner. On your hands and knees, push it where you want it to go. The liner is durable enough to walk on, but it can be sliced easily. The liner should mimic the underlayment. It should extend beyond the pond 12 inches or so all the way around, including the skimmer box and waterfall.

At this time avoid the temptation to trim the excess liner. That will all be taken care of when we do all our finishing touches.

How to Rock in Your Pond

build a pond using pond liner and natural stone

Let the fun begin! Let’s start putting all the “pieces” together. This may look intimidating but just take it one step at a time and you will see exactly how to rock a pond. This will be the time when all that hard work pays off. Your pond will come to life right before your eyes!

With the liner in place it’s time to begin placing rocks around the perimeter of your pond. Start at the bottom and work your way up. Dry stacking can be tricky, the rocks need to fit well together so they lock in place. This is a very tedious task.

building a pond with a fish cave using natural stone

Make sure the rocks are placed in the corner where the bottom meets the step. Never go higher than two rows where the seams line up without putting a rock across. You can see in the picture what I mean. This helps add stability. Place larger rocks on the bottom row and build up from there. Be sure to set aside the best looking rocks for the very top of your pond, where the waterline will be.

build a pond with natural stone and layers

Do not concern yourself with the liner too much when laying the rocks. The liner is tough and flexible. Rocks can be placed on the liner without worry.  Try to avoid dragging the rocks across the liner, as it can be easily sliced.

Another way to add stability is to use waterfall foam. It’s similar to spray foam insulation used to seal up cracks around the house. This foam is a dark gray so it can be easily concealed. Use it sparingly, as it will expand as it cures.

build a pond with natural stone three layers rocked in

Fill all gaps with gravel first, this helps save on foam. Add a small amount of spray foam, then more gravel to hide the foam. Use gravel to fill in any large gaps as you go, again this adds to the stability of the entire pond.

Submersible Pond Lights

Another thing to remember at this stage is to add any submersible lighting. Be sure to hide all the wiring as you go. The kit I used came with only one submersible light. Looking back, I should have used a couple more, but that will be a project for another time.

Here is a little tip: If your light has excess wire, wrap it around the light and then put it in place. This way when you go to change a bulb you can pull it up without having to dig up the wire you fished through the rocks.

Building a Dry Stack Stone Wall – Underwater

As you can see you will need a lot of rocks! The goal here is to essentially build a dry stacked stone wall. Save the biggest boulders for your waterfall itself. Notice how in nature, a stream and waterfall are usually framed in by large rocks and boulders. If you try to mimic nature, you can’t go wrong.

Once you’re done with a layer fill the bottom up with about two inches of gravel. I used river rock for mine. There are all sorts of gravels you can use depending on the look you are going for and what is native to your part of the world. Keep moving up one layer at a time. Stop rocking when you reach your skimmer box.

Setting the Skimmer Box

Be sure the hole you dug out for your skimmer box is flat on the bottom and the dirt is compacted below it. Once you put your skimmer box into place you don’t want it to settle or move.

Place your skimmer box in the hole and check that it’s level from side to side, and front to back. Remember, your water line will be approximately ¾ the way up from the bottom of the skimmer box opening.

Read the Directions

Before you begin it’s a good idea to read over the installation manual that came with your skimmer box, so you can familiarize yourself with it.

pond installation setting your skimmer box

Now push your liner into the corner where the skimmer box meets your first shelf. Allow for some slack there. You don’t want any tension on the liner around the skimmer box. Now lay the liner vertically across the face of the box, so that it sits flat. Now, using a nail or other sharp object poke a hole in the liner in the top right corner where the first mounting screw will go. Do the same for the other side all the while holding the liner steady.

Keep the nails there to hold your liner in place. From inside the skimmer box using a pen or marker, trace the opening. Fold the liner toward you and keep the nails in the liner. This will help to realign where you dry fit the liner.

pond installation attaching your skimmer box to the pond liner

Now place a ¼ to ½ inch bead of sealant about ¾ inch in from the opening you traced. Be sure the bead is continuous and there are no gaps.

Using the nails that are poked through the liner as guides place the liner against the skimmer box pressing firmly all around the opening. Rest the mounting plate on the nails. Remove the first nail and place in the first screw. Do the same for the other side.

Now using a nail make a puncture where the next screw will go, then install the screw. Do this repeatedly all the way around the mounting bracket until all the screws are in.

Hook Up Your Submersible Pond Pump

submersible pond pump

The skimmer box is in place, now is the time to attach your submersible pump to the waterfall return line. When hooking all the pieces up it goes pump, check valve, then return line. Be sure to install the check valve in the proper orientation, since it allows water to flow one way only.

All the connections are made with rubber boots and hose clamps. Be sure to orient the hose clamps so you have easy access to the screw. This will help during spring startup or any pond maintenance and you need to remove and service your pump in the future.

Finish Dry Stacking the Rocks

With your skimmer box set, finish rocking around the whole pond. Once you’ve completed a step, add gravel to the bottom and move on. When you get to the last course be sure to mix large and small rocks to make it look more natural. Be sure the rocks go up and over the bank of the pond.

dry stacking rocks for a backyard waterfall pond

When you are stacking the rocks try not to rely on waterfall foam. Make the rocks ‘fit’ together and lock on their own.  Use small rocks and stones between larger ones to lock everything into place. If you are using waterfall foam be sure to hide it with small rocks as you use it. Don’t over do it with the foam, and keep in mind that it does expand.

How to Build Your Waterfall

using character boulders to frame in a backyard waterfall

Keep in mind as you build your falls, that if you want to add any lighting, now would be the easiest time to do it. It may be more difficult to hide if it’s done later. I used a strip of waterproof led lights tucked under two of my spill rocks. This lighting allows me to change the color with a remote.

The effect is, really cool. Check out the video and pictures. As you build up from where the water line will be, make sure you “frame in” your waterfall. Mimic nature and you will have something spectacular! Use large boulders on the edge and flat slate for the spill over rocks.

backyard waterfall pond with color changing LED lighting

Setting Your Waterfall Spillway

Setting your spill over rocks can be tricky. You want the water to run over them properly so be sure they are set level across, and pitched slightly forward. One thing to look out for is to be sure the water doesn’t run behind them.

setting spillover rocks building a backyard waterfall pond

This is where the waterfall foam comes into play again. You won’t know for sure how the water will flow until you actually turn your waterfall on. If you foam between your spill over rocks and your liner, the water should flow over the rock instead of behind it. Hide all the foam with gravel before it cures completely. Stop rocking when you get close to the waterfall unit.

Attaching Your Waterfall Unit

There may be specifics that aren’t mentioned here, so be sure to read the manual that came with your waterfall unit. Just like previously when we attached the liner to our skimmer box, we are going to follow the same process. The key points are the same.

  • Be sure there is no tension on the liner
  • Make sure the liner goes beyond the waterfall
  • Use one continuous bead of sealant
  • Have no wrinkles in the liner between the waterfall and the mounting plate
  • The sealant goes between the liner and the waterfall, NOT the liner and mounting plate

Go All the Way Up

Allow your sealant to cure, and continue to build up your rock framework. Continue rocking up to the waterfall unit. Use larger rocks as a border. Be sure the liner is under the bordering rocks. Backfill behind the liner with dirt or other rocks to hold it in place.

build a pond fully rocked in over rubber liner

Again, avoid the temptation to trim the liner at this point. It will be done with all the finishing touches later after everything is up and running.

Dry Water Garden Pond

Once you’ve covered everything with rocks, it’s a good idea to wait at least 24 hours to let all the sealant, and waterfall foam cure. Everything needs to be washed down at this point. I purchased a cheap, dirty water pump from amazon to accomplish this. If you have encountered any rain during any of this, the pump is handy for that as well.

Spray down all the rocks with a garden hose and pump the dirty water out of the bottom. It’s amazing how much dirt is actually on the rocks and gravel. Keep doing this until the water is fairly clear. Don’t get crazy, you will never get it all.

Pond Filter Media

The kit used in this writing came with the needed filter pads. For an extra layer of filtration it’s a good idea to add lava rock to your waterfall unit. This will help with the formation of beneficial bacteria that will keep your water looking great all season long.

Rinse the bag of lava rock to remove all the dirt and dust. Then place it in a mesh bag in your waterfall unit. The lava rock will house the beneficial bacteria that will help to break down waste and keep your water clear.

Fill the Pond

Time for the moment of truth. Start filling your pond. This may take some time, depending on the size of your masterpiece! At this point it’s a good idea to test your lighting systems and make sure everything is working properly. At least that’s what I told myself… I am a bit impatient and I couldn’t wait for nightfall.

Fill up new pond build with water and check for leaks

In all reality, this is a perfect time to sit back, grab a drink, and relax a bit… you deserve it. All that digging and stone work takes its toll. Once the water level is where it should be, about ¼ of the way down from the top of your skimmer box opening its time to test the system.

Avoid the temptation of turning on your submersible pump too early. If it runs dry you will do damage to the pump, so be patient.

Make sure you have an audience, and a drum roll is a must! Turn on your pump and watch your backyard come to life as you add a new dimension to your outdoor space. Let your pump run for at least 24 hours and keep an eye on your water level. If it goes down you may have an issue somewhere and will need to resolve it before you go any further

relaxing backyard waterfall koi pond

If your water level goes down don’t panic. The most common reason for this is water is splashing out, or getting around the liner somehow. This can usually be resolved with waterfall foam and redirecting the water flow to stay within the liner.

Backyard Pond Designs

Backyard pond designs are a direct reflection of your personality and taste. This is the time to let your creative ideas run wild and showcase your amazing water feature. Just like furnishing a new home, it’s time to add all the finishing touches that can really enhance your amazing creation.

backyard pond at night

First, let’s discuss the necessary steps that need to be taken to finish the project. After that it’s up to you. That’s when you can let your creative side go wild. If you choose to surround your water garden with garden gnomes, so be it. Let’s get started.

Finish the edges

At this point you’ve filled your pond and are running your waterfall, but the entire thing is bordered by wrinkled rubber liner. Take the excess liner and wedge it between two rocks, so that it is sticking up between them, then trim the excess.

excess pond liner to be trimmed

I know it sounds like common sense, but be sure your liner is higher than your water line, or you will have issues. This may be tough to see at some points, especially where the water flows down your waterfall.