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“Check for uniform water distribution and overlap with any irrigation system by placing five broad, wide-mouthed cans diagonal to the sprinkler at distances of approximately 20, 40, 60, 80, and 100 percent of the maximum throw of the sprinkler(s). Collect the output, note how long you ran the system, and the average depth of water collected in the cans. This test will do several things for you. First, it will help you diagnose and prevent either dry or saturated areas that can lead to an unhealthy turf. Second, it will allow you to determine irrigation application rates so that you will know how long you can (or want) to run your irrigation to deliver a desired amount of water to your lawn.
For instance, assume you have determined, (or your Extension agent has recommended) that it is necessary for your turf to receive one inch of water per week to perform its best during the hottest, driest months of the year. By using the can collection system described above, you have determined that you need to run your system 60 minutes to deliver one inch of water. However, you also notice that at about 30 minutes into the irrigation event, there is significant puddling on your lawn, telling you that your soil is not accepting the water as quickly as it is being applied.
By knowing what your system is capable of delivering, and paying attention to how the soil accepts the applied water, you can develop a responsible irrigation program in which you run your sprinklers for no longer than 30 minutes per irrigation event in order to avoid puddling and the undesired loss of water due to surface drainage. This will provide a half inch of water and you can now schedule two irrigation events during the week in order to deliver the desired volume of water. Such a strategy maximizes the efficiency of water use and promotes a healthy turfgrass system at the same time. ”
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http://www.ext.vt.edu/pubs/turf/430-010/430-010.html