If you have a rain collection system then the drip lines are placed in and around your planting beds and and opened so the water will drip continuously providing enough water to the plants but not so much that it drowns the plants...and can be shut off either by hand or a moisture guage to prevent over watering when it rains..unless your talking about watering your whole yard then you would run the drip lines in a pattern that would cover the entire yard and then the water collection system could be set to water the whole yard on a timer allowing 1" inch or equivilent with the rainfall by using a metering guage...or unless your talking about farm drip/sprayer irrigation then you you would probably have wells hooked up to the motorized overhead sprayers allowing irrigation even when it does not rain to grow crops...look on my page for a home rain collection system you can do yourself...
