You must be on a well, wouldn't be all that uncommon.

Hi Perkins...

If you see this "dirt" mainly in the hot water lines then most likely, what you are seeing is sediment that has been disturbed from the pipes when you recharged the water supply to the new water heater.

Here, when the water leaves the water heater for the first time it is mixed with water and air and the flow is very TURBULENT and disturbs the sediment along that bottom of the hot water pipes that usually sits still via gravity when water flows in a LAMINAR manner.

Run the water for awhile and it should clear. Then remove the aerators at all your faucets to clear them of any sediment that collected.

If you find the dirt issue in both hot and cold then most likely, it is a problem associated more closely with what Hkstroud suggested... ;)

Questions? Let us know, OK?

Mark