Low water pressure

I had a pvc water pipe break in my yard. After an all day effort I was able to repair it. During the repair some dirt, not a large amount, fell into the pipe. Water to the house is restored but I have extremely low water pressure in only 1 tub (both hot and cold) and the washing machine. Water pressure everywhere else is ok. Could it be debris blocking the lines? If so, what is the best, least destuctive way to track down the source of my problem? Thanks in advance.