Yes, trenchers can go through gravel. Gravel is made up of smaller, softer rocks that certain trenchers are able to cut through. Just be sure to use a rock wheel trencher or chain trencher, both of which are made to cut through rocky landscapes and gravel pathways without dulling the teeth or chain.

Professional installers often include a deep layer of crushed gravel under permeable pavers to allow more runoff to soak through into the soil below. Many installations will include multiple layers of gravel, with coarser aggregate at the base and finer aggregate that sits on top of that bottom layer. Above the gravel, you’ll often find coarse sand that helps reduce paver shifting over time. Some permeable paver designs include a water collection system set into the gravel layer to route runoff to a safe area for disposal.

The average cost for pool excavation is $2,500. This cost can range from $450 to $4,500, depending on the pool shape and size, time of year, and any need to move buried utilities. 

When excavating for your pool, you might have to move existing utilities. You can expect to pay an additional $15 to $25 per linear foot to move gas lines. To move a septic system, it’ll cost an additional $2,000 to $20,000. A pool that is 10 feet by 12 feet averages $450 to excavate, and a 20-foot-by-40-foot pool averages $3,020.

Above ground pools are not buried in the ground. Typically, above ground pools are semi-permanent. One reason they’re more affordable is that you don’t have to dig for an inground pool and pour concrete or another material. However, you can choose to install a semi inground pool, which is a hybrid between the two.