Build a concrete retaining wall

1.1. Use a cotton string and stakes to position the wall. Provide a minimum 12" space at the back of the wall for 0-¾" drainage gravel, and 12" at the front to support the wall.

1.2. Dig a 6" deep trench, allowing an additional 10% of the height of your wall as additional depth. This will let you lay the blocks into the soil.

1.3. Cover the back and bottom of the trench with a geotextile sheet. It should be longer than the height of the wall by at least 12"; you'll use the extra length to cover the drainage gravel.

2.1. Spread 6" of gravel over the entire surface of the soil.

2.2. Use a mechanical compactor to compact the gravel, and make sure that the foundation for the first row of blocks is level.

2.3. Place 1" of stone dust and compact again.

3.1. For the base of the wall, lay the first row of blocks, making sure they're level.

3.2. Install a 4" diameter perforated drain pipe behind the wall.

4.1. Lay the following rows in such a way as to make the joints overlap.

4.2. Backfill the back of the wall with 0-¾" gravel after installing every second row. The first backfill should cover the perforated drain located just behind the first row. This should be done manually, not machine-compacted.

4.3. Lay the cap blocks on the top in needed.

5.1. Fold the geotextile sheet over the drainage gravel.

5.2. Cover the geotextile sheet with soil or another material as well as the gravel at the base of the wall.

5.3. Replace the strips of sod and water the grass.