It does get cold here in the winter. I've had a self-draining sprinkler system for 20+ years but I need a new lawn and better sprinkler system. The companies I've talked to refuse to do self-draining. One company would do self-draining but not warranty the job. The all prefer to blow the system out every year. Is there any good reason to not do self-draining. How deep should I have them bury the black pipes if I can find anyone to do it? They say they bury them 6 inches. Is that enough for self-draining?