I live in a city with a very particular planning department that's requiring me to install a large drywell beneath my new driveway. I'm a bit concerned about this because the contractor suggests placing the drywell directly under the driveway made of #2 crushed stone, which is about 9 feet wide and 115 feet long. The city mandates that 30% of my plot must remain permeable, so I'm using granite crushed stone since it interlocks well. The drywell's size is massive at 8x9x10 feet, but due to a small front yard and utility lines, there aren't many alternatives for placement. I'm worried that the weight of four cars driving over it daily, plus the occasional U-Haul, might compromise the drywell. The contractor insists it'll be fine since it will be centered under the driveway and have several feet of stone above it. Has anyone dealt with something similar or can offer advice on this?
1 Answer
You might want to consider using permeable paver driveways instead. They can help distribute the weight more evenly over the crushed stone, which might be what you need to avoid any issues with the drywell collapsing.
So, you're suggesting that the weight distribution would be better with pavers than just with crushed stone? I get that it's a cost concern, but maybe it's a worthwhile option to explore!