Yellow colored water: Usually caused by a disruption in water system caused by a break or flushing the system. Water rerouted through different mains can cause water to pick up natural minerals that are in water. Water is safe to drink and should clear up in two days, if not call the water department. Try running the cold water only for about 10 to 15 minutes just at one faucet. When the cold water no longer looks dirty turn on the hot water and run it until the water is clear.(By not running the hot water until the cold water is clean, you'll keep discolored water out of the hot water tank.
Milky colored water: This is air in the water. To remove air from line, try running a faucet at the highest location in the house for about 15 minutes. If caused by a break in the system it should clear up in about two days, if not call the water department.
White particles clogging faucets: This may be the result of the filler tubes in some hot water heaters breaking down. It's most likely to happen with water heaters manufactured between 1993 and 1996. The plastic in the filler tubes sometimes breaks down into granules that look like powdered soap. According to the filler tube manufacturers, the problem has been solved. A replacement tube is available for about $5.00 and can easily be installed by a plumber or handy homeowner.
Low water pressure at one faucet: Check to see if filter screen is plugged. You can unscrew the screen and clean it
Low water pressure at more than one faucet: Check to see if shutoff valve if open all the way. This is located before the meter
Your pressure regulator may not be working properly. You will need to have a plumber test and replace the valve.