Quite possibly the only thing better than being under a shade tree in the summer is taking a dip in the pool. If you are planning to build an in-gound pool near one of your prized trees be careful. You are going to be digging a big hole in the ground and will likely be taking many tree roots in the process.
The kind of tree you will be working around will be a big factor regarding the amount of disturbance the tree will tolerate. For example, live oaks will take a lot of abuse; I’ve seen pools built within a few feet of the trunk of a live oak and the tree survived. American Elms, however, do not fare well after substantial root injury.
My general rule of thumb for any construction around trees has been to try and give at least 15′ of clearance from the tree trunk. If you are digging or leveling the soil within 15′ you are asking with trouble. This holds especially true when digging out for a pool.
A good thing to do before you start digging is to use an airspade and dig some trenches to find out where you have big tree roots. An airspade is a high powered air compressor that can blow away dirt without damaging tree roots. Doing a few test digs will give you an idea of how much trouble you are getting into.
Regardless of your exact proximity to the tree trunk, any trees near the pool should be put on a fertilizer regimen to help the tree repair wounds and regrow root system. Often, trees that are not right next to the pool, but adjacent to the path used for equipment access get damaged, too. Don’t forget about these trees.
High traffic areas around the pool and along the access path should be de-compacted using and airspade to restructure the soil. This is critical to providing the trees a good soil environment for the roots to regrow.
The bottom line is that pools can be built near trees without having to sacrifice the trees. But, certain steps must be taken to ensure your pool design allow for sufficient tree preservation measures. You should go into the design process with an open mind and willingness to sacrifice some pool features to save your tall green friends.