For the past week I have noticed a change in the coloration of our water. It is leaving a brown residue in our comode and in the bath tub. Today our well, which is located in the front yard of our house, is making a hissing sound which I have never heard before. Our home is 30+ years old. Can you tell me what could be the cause of this hissing sound coming from the well cover?

Sounds like you have a broken pipe between the well head and the house.

Does it hiss all the time, or only when the pump is running?

Is the pump in the well, or above ground?