If you have a plastic water shutoff valve, you need to test it to see if it turns easily and it is not stuck. If it is stuck, you can replace it with a metal valve, or buy a special wrench that will allow it to turn without breaking off the plastic handle. Here is one that I bought in the 3/4 inch size and it works very well. If you have a sudden leak, you need to be able to turn off the water quickly.
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