The process of excavating for the pool generated a lot of dirt. Having it removed would be extremely costly so we decided to use it to partially level the yard below the pool. This area is around 25 meters wide and 10 meters deep. The elevation difference from one side to the other is around 1.5 meters and from top to bottom around 1 meter.
The intention was to maintain the current direction of the slope (away and to the right when viewing the above images), but reduce its magnitude significantly. Once this was done, we would then attempt to fertilize it and reintroduce turf, although it was challenging to envisage this level, green oasis when looking at the result of the excavation:
Mountain of dirt resulting from the excavation.
View from atop the mountain of excavated dirt.
Leveling
The smart move at this point would be to hire some sort of dirt moving machinery and proceed to move the dirt into position. With no budget for that, it instead became a seemingly endless process of digging, wheel barrowing, and dumping - a Herculean task given the volume involved.
Thankfully (for me at least), I subcontracted this task out to family member. Several of them in fact. And over the course of several months, the area was leveled.
Leveling process approximately half complete.
Using a laser level to get the correct slop on the final surface.
Compacting
The process of excavating loosens the dirt considerably, and when it is replaced onto the ground, there is much air trapped within. If left in this state, it will gradually consolidate over time, sinking unevenly and resulting in a knobby, uneven surface. To hasten the process, we used a rammer. This device has a large metal foot, which - as the name implies - rams the earth with great force to compress and consolidate it.
Using a rammer to consolidate the newly leveled ground.
Once the consolidation process was completed, we were left with two major impediments remaining before we had any hope of successfully growing a lawn. The first was caused by the very compacting we just undertook. Grass needs aerated soil to thrive. The soil needs to be permeable to water and not too dense to allow the roots to grow healthily. So the top 100-150mm of soil needs to be aerated.
The second was the poor quality of the soil itself. The excavation produced some high quality topsoil, some sandy, silty soil, but a much larger quantity of clay. This all got mixed together during the leveling process and the quality of the resultant surface was less than ideal. The solution for this is to add a large quantity of organic matter.
Fertilizing and planting
To address these issues, we hired a rotary hoe and proceeded to mix a large amount of compost and some sand into the top layer of the dirt.
Rotary hoe and other tools being delivered.
The hoe uses rotating blades to dig deep into the soil, introducing air and lowering the cohesion. Once the entire surface had been loosened, compost and sand were spread and the hoe used to combine them with the top layer. Finishing with a leveling rake and water filled roller completed the surface preparation.
With the soil enriched and aerated, it was ready for planting. Not much to discuss here. Aside from throwing down a lot of seed and keeping it consistently wet, it’s basically a waiting game.
Strong growth after two weeks or so. The vegetable garden can also be seen to be growing well.
The new surface is much more level than before while still maintaining appropriate drainage.