Proper maintenance of an irrigation system is required to insure efficient uniform irrigations. Ensuring that the sprinklers and emitters are working properly is a major part of irrigation system maintenance. The following items help keep sprinklers operating properly.

• Keep heads properly aligned, leveled, and rotating.
• Clean plugged sprinklers, emitters and filters when needed (figure 7).

• Replace broken sprinklers, worn nozzles and emitters with appropriate parts to maintain matched application rates and uniformity.
• Keep grass and plants away from sprinklers so spray patterns are not disturbed by them. Raise sunken heads.
• After evaluation move, add or remove sprinklers and emitters to make a more uniform application of water.

Visual inspection of the landscape provides a good indicator of irrigation problems. Both stressed (hot spots) and over irrigated (soggy spots) areas indicate irrigation problems. If the irrigation system is operating improperly the following items should be checked.

1. Water supply — Check to see if all valves are opening and the system has proper pressure.
2. Controller and controller programming -— Check the controller to make sure it is operating and programmed properly.
3. Field wiring — Check to see if the automatic valves are receiving the proper voltage and current, check for shorts in the wiring.
4. Valves — Use the controller to manually operate the valves through a cycle to make sure they are operating properly. Adjust the flow control stems on the valves if needed.
5. Sprinkler heads — Check for plugged, blocked or broken heads. Make sure the sprinkler is rotating properly.
6. Pipe and fittings — Check for broken or plugged pipes and leaks.