How to Build a Pond – Allan Block Wall Systems

Enhance your flower garden with a beautiful pond using the AB Courtyard Collection. With this flexible system you can build a pond in a weekend without any special tools and without splitting blocks.

In this example we are building a 6 ft (1.8 m) diameter pond with a pre-formed liner (found at your local pond supply store) on soil. If you are constructing your pond on an exisiting concrete surface, skip to Step 4.

Place a stake in the center of where you would like to build your pond. Measure the diameter of the pond liner, then mark on the string one half of the diameter. Tie the string to the stake and rotate it marking the ground for the liner. Temporarily place 30 AB York blocks along the outside of the circle marked on the ground. The amount of blocks needed is based on the pre fabricated liner that was used. Verify the liner size and adjust blocks as needed to fit the design. Use a shovel to cut around the blocks and mark where the sod and soil will be removed to construct the base.

Remove the blocks used to layout the pond location. Then remove the sod and 3 in. (76 mm) of soil in the entire area. If your plans includes a decorative center sculpture or fountain it is recommended to remove additional soil in the center to construct a stronger base. If electricity is required please follow local electrical codes.

Next prepare the foundation pad by placing 4 in. of well-graded base rock in the excavated area. Level the area making adjustments where needed. A straight 2x4 and a level make easy work of leveling the site. Compact the base rock with a hand tamper.

Start building the pond using the string to position the blocks. Building two courses at a time will insure proper alignment. Check the blocks for level. Make adjustments to the circumference of the circle so that cutting is not required. Next add the third course of blocks.

Place the pre-fabricated plastic liner in the ring of the blocks. Position the panel caps and glue them down with concrete adhesive. This will lock the blocks together and prevent unwanted disassembly.

Place your choice of clean decorative rock in the bottom of the liner. Now you're ready to add water and other ornamental accessories to customize your design.

Above Ground Pond

This below ground pond will use 4 courses of AB York blocks, Wall Caps, a flexible pond liner, which can be found at a local pond supply store, and a fountain (optional).

When completed the pond will be an outstanding element in your yard. The liner we are using will be placed on the outside of the blocks to allow the AB Courtyard blocks, decorative rock and fountain to be the main focal point.

First, choose the location for your pond and place a stake in the center. Using a tape measure, mark 41 in. (1.04 m) on the string starting at the stake. Using paint and the string, mark a circle around the stake at the location of the pond.

Temporarily place the AB York blocks along the inside of the circle marked on the ground. Each course of the pond will use 28 blocks to complete the circle. Adjust blocks as needed, making sure the blocks are tight together. Use a shovel to cut around the blocks and mark where the sod and soil will be removed.

Remove the blocks used to mark the pond location. Next clear any existing landscaping in the entire area and dig a hole a minimum of 12 in. (300 mm) deep to accommodate the pond. Later, we will be using some of the removed material as backfill to add a gradual slope up to the ponds edge.

In the bottom of the hole, dig a leveling trench 8 in. wide (200 mm) by 3 in. deep (75 mm) around the outside of the pond where the blocks will be placed.

Leveling Pad

Level Blocks

If there will be a statue or fountain in the pond, dig a leveling trench for its location as well. Fill the leveling trench(s) with 3 in. (75 mm) of course sand. Compact the bottom of the pond and the sand leveling pad with a hand tamper.

Use a level and a straight 2x4 to level the entire pond area from side to side. A level base will make it easy to install the rest of the pond. If electricity is required for a fountain, please follow local electrical codes.

Temporarily place the first two courses of AB York blocks on the sand leveling pad. Building the first two courses at the same time ensures proper alignment. Level and adjust each block from side to side and front to back. Once the first two courses are in place. Use a level and a straight 2x4 to level the blocks from side to side across the pond.

Before adding the liner, carefully remove all the AB York blocks. The blocks must be leveled before the liner is installed to prevent damage to the liner later. When installing the flexible liner, be sure to press the sides of the liner into the outside edges of the pond. Be careful not to step or stand on the sand leveling pad.

With the liner in place, carefully replace the first 2 courses of blocks in the location of the leveling pad. To avoid damaging the liner later, make only minor adjustments if possible to re-level the blocks. With the first 2 courses complete and leveled, install the 3rd course.

Modify block to make room for the power cord

Install power cord and blocks

With the 3 courses installed, fold the liner up over the top of the blocks. Using onsite soils, backfill around the outer edge of the liner up to the top of the blocks. Gently compact this soil to prevent settling of the soil later. Using a utility knife, trim the excess liner at the outer edge of the top of this 3rd course of blocks. Remember that the high water mark can not exceed the top of the cut of the liner. For deeper water levels, you must bury more courses.

Install the last course of blocks. If the pond needs electricity, chip off the bottom edge of one block using a hammer and chisel to make room for the power cord. Follow individual manufacturers instructions on proper installation of any accessory you will be adding to the pond.

Finish the pond with Wall Caps. Then secure in place with concrete adhesive.

Its time to add the water, decorative rock, a sculpture/fountain or plantings. When using rock, we recommend rinsing the rock before placing in the pond for best results. Finish the landscaping around the pond with mulch and plantings and enjoy.

Above Ground Pond

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How to Build a Pond - Allan Block Wall Systems