| Major problem here. If your new pool is 3-4 inches out of level you need to fix this. Your pool could weight 75-100,000 pounds when full. Trying to block up the low side to be level with the high side is a risky proposition.
Professional recommendation is to dig the high side down to the low side, basically starting over. Good luck with your project.
Steve Goodale
Serendipity Pools |