View Full Version : White milky water

12-22-2008, 12:02 PM
Hey Guys,
I can't for the life of me figure this one out. I supervise trades personnel at a small commercial building. Recently, we had a 12" water main break about 200 yards away from the building. We replaced a 12" gate valve that was broken, flushed the line at a fire hydrant 50 yards prior to the building and then set about purging air from the rest of the facility. This includes three showers, twenty-two sinks, nine urinals and nine toilets. Everything seems to be fine except that the hot water comes out of the faucets looking like 1% milk!! If you let it sit in a glass or bowl for a few minutes it clears right up as there is no residue in the glass so it appears to be only really fine air bubbles. We have not made any changes to the hot water system which is a two year old electric unit with a circulating pump. I'm not receiving complaints about the hot water but it looks terrible! Any thoughts on what I might look for as the problem? Thanks.

Ian Gills
12-22-2008, 12:42 PM
Surely this is just air that will disappear, as you point out.

Perfectly normal following a leak of that magnitude.

WV Hillbilly
12-22-2008, 01:46 PM
Milky color
Water contains dissolved oxygen and other gases. When it's heated it has less ability to hold these gases and when the pressure is lowered as the liquid comes out of the tap these gasses can form tiny bubbles giving the liquid a milky appearance. Letting it stand for a few minutes will allow these bubbles to rise out of the liquid and it resumes its clear appearance.

12-22-2008, 02:56 PM
It's air and it is probably a suction leak at the valve causing it.