A lot of us city folk could care less about the amount of rain that falls. When rain falls here in Los Angeles, all it means to me is stay off the freeway. In farm communities, however, rain is ridiculously important. At your local filling station, the farmers will be gathered around the Lotto machines talking about the rainfall their farmsteads have received.
Knowing how much rain has fallen is important, especially in the city and especially if you have a lawn. The average yard needs only one inch of rainfall per week to survive. Many people over water their lawns because they do not measure or know how much water is needed for the grass. This needs to stop. There is no point in playing guessing games when a rain gauge can be built out of accessible household items. A rain gauge can be your guide to water conservation.
To build a rain gauge, you simply need a ruler and a can or a jar. The can should have a fairly wide mouth. Some recommend a tuna can, but I fear that a tuna can isn't deep enough, and some raindrops may bounce or splash out. I recommend a baked beans can or something of that ilk. Measure an inch from the bottom of the can. Mark it with a permanent black marker or cut a notch with a knife.
With a jar you can get a more accurate reading. Simply tie a small ruler to the neck of the jar. When it rains, measure the depth with a ruler. Do not place the ruler in the jar with the water or you will get an inaccurate reading. Or you can use math to subtract the volume of the ruler from your measurement, and Eureka! Your reading becomes accurate again. Math is eco-friendly.
Use this gauge to make sure that your yard gets the amount of water that it needs and nothing more. Save water and reuse a can or a jar. It's the responsible way to maintain a lawn.