Irrigation system woes

As our system continues to age (currently about 21years old), it conitunes to drain exponitianlly on dollars and personel.  We currently have drained the water from our entire system in order to repair two seperate leaks (#13 fairway and #4 tee box).  Draining all of the water in an irrigation system in our part of the world is an option reserved for only a last resort.  We also, have had some reapirs to #1 and #2 fairways.

 #1 Fairway

#13 Fairway

#2 Fairway