Today's Standards For Proper Irrigation Backflow Prevention The State of Connecticut requires all municipal water-supplied irrigation systems to use a reduced-pressure device such as a Febco 825-Y or equivalent. Controllers Computer-controlled irrigation systems allow more flexibility in scheduling and, with proper management, can save water. Rain Switch Rain switches save water by interrupting scheduled cycles during rainy weather and allowing more freedom for the operator who monitors the controller schedules. Sprinklers Sprinklers should be sized to the area to be watered, the water supply, and the water pressure. Matched precipitation sprinklers allow even distribution of water. Valves Valves with manual override and a flow handle allow for manual watering and shutdown of valves that need service while the rest of the system is left in operation. Valve Boxes Valve boxes provide a location point for valves and ease of future service. Wire Multi-strand cable allows spare wires for future expansion and double-jacket protection. Drip Tubing Pressure compensating dripperline puts water at the roots of the plants, not on nearby structures. All drip zones should be regulated with a pressure reducer. Piping All piping under continuous pressure should be PVC 200 PSI. PVC pipe can withstand higher pressure than poly pipe, and fittings are less subject to leaks. A main line with 80 PSI static pressure could have spikes to 170 PSI or greater, due to "water hammer" caused by a quick-closing valve. Lateral lines are placed after the automatic valve and can be 100 PSI poly pipe. These lines are under pressure only while the specific sprinkler zone is operating, and at a reduced rate of pressure due to water being released through the sprinkler nozzle. There are two types of poly pipe: medium density #2306 and high density #3208. Both can have the same pressure rating. Medium density pipe is better suited for lawn irrigation because it has more flexibility and is less susceptible to splitting and kinking. Pumps Booster pumps should be considered if the pressure at the farthest lawn sprinkler is less than 35 PSI operating pressure. A sprinkler with too little pressure will not provide even distribution of water; a sprinkler with too much pressure will mist, allowing wind drift and poor distribution.