Hearing a train when turning on the tap

The Associated Press
Friday June 29, 2001

Q: I open any tap in my house and I hear a train-like noise. It also feels as if air is being sucked into the tap. When we use two taps, the noise disappears. Using two taps is not a permanent solution. So tell us what kind of problem we are facing and how to fix it. 

A: If faucets screech when you turn them on and pipes hum when water’s running, chances are you have a bad main inlet valve or a bad pressure- regulator valve. Water enters a home at only one point, and if all faucets groan and howl the same all through the house, the main inlet valve is bad where water enters your home.  

Over time, rubber gaskets can become brittle. Running water rushes in, passing over the gasket and acts like the reed in a clarinet with pipes carrying the sound to every faucet and fixture, making it hard to pin down the source. In this case, check the main inlet valve, but if it screeches at only one location, then check the gasket of that particular faucet. Repairs can be done with basic tools, for under $10. 

Q: I have well water in my home and of course the water smells. Someone told me if you take out the rod in the water heater, the water won’t smell anymore. But what rod is it and how do I get it out? 

A: The problem occurs when the metal rod in-glass lined water heaters (used to improve the life expectancy of the glass lining) combines with waterborne sulfate-reducing bacteria (not harmful to consume), resulting in the production of hydrogen sulfide. The water is not dangerous to consume, but is difficult to swallow if you dislike the smell of rotten eggs. 

Solution 1: Replace the magnesium metal rod (cathodic protection anode) with one made of aluminum (it might not be available for your brand water heater). The aluminum rod produces 30 percent less current and therefore generates less hydrogen gas, while causing enough current to adequately protect the glass liner. 

Solution 2: We do not recommend this alternative. Doing so will void the manufacturer’s warranty. Unscrewing it from the tank and replacing it with a threaded plug can accomplish complete removal of the metal rod. 

Solution 3: Find the origination point of the sulfate-reducing bacteria (SRB) and eliminate it. SRB is most prevalent in new-water supply pipes contaminated by soil during construction.  

The soil carrying the SRB eventually ends up as solids at the bottom of the water heater. A thorough flushing to remove the dirt, then a second flushing with a dash of chlorine, and finally a third flush to clean should do the trick. Hydrogen gas without the presence of SRB will go unnoticed. SRB is not so easy to remove if your water company pumps the bacteria into your home right along with the water. This will, in fact, be the case as increasingly water districts continue to reduce or cease their use of chlorine (as many have). Sulfate-reducing bacteria are devastated by chlorination, but will thrive otherwise. 

It is possible to inadvertently contaminate your own water supply by allowing sulfate-reducing bacteria (not to mention other more dangerous bugs) to enter your water system at your own property through your sprinklers, for example, by not using anti-siphon sprinkler valves, which prevent “backwash.” Backwash could also result when a water main in your neighborhood is turned off while your garden hose is running in a muddy puddle.