Drainage in my new yard and under my home.

Water is a good thing unless it is collecting under you home. When your builder builds your home off the ground make sure the ground under your home is higher than the yard outside and has enough headroom to sit up and work comfortably, If your home is in a low lying area a sump pump and humidity controlling fan may be necessary to remove water and moisture that accumulates under your home. Make sure your builder does not install your ductwork in the crawl space if you live in the Southeast USA. Condensation and moisture will build up and cause damage to wood floor framing, sub-flooring, and hardwood flooring in your home unless you make the crawl-space conditioned. Sand around 3"-6" will help but an additional moisture barrier may still be necessary to keep the crawlspace free of moisture.