If this is for an above ground swimming pool, I would level the ground before putting up the pool. Otherwise, the weight of the water might collapse one of the walls of the pool.
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You need to have your ground completely level. If it isn't level then you are going to have bumps and inconsistencies all over the bottom of your pool.
If you don't level an above ground pool perfectly, your sides will buckle!
The cost of swimming pool repair can vary depending upon whether or not the pool is above-ground or in-ground. Above-ground pool repairs will generally be less than $25. In-ground pool repairs ranging from $500 to $1,000 are not uncommon.
With a tape measure.
The cost of above ground swimming pools vary by make, model, and location. However, for a basic quality swimming pool, expect to pay at least $3,000.
16x32 above ground doughboy swimmimg pool.
Probabily the ground surrounding your pool if its in-ground. In an above-ground pool they most likely fly into the pool or crawl into it from the sides.