Iron and Manganese

Refer to "Color, Taste and Odor Problems in Drinking Water" for general information about aesthetic problems with drinking water.

Sulfur or rotten egg taste or odor is most commonly caused by bacteria growing in your sink drain or water heater. But, in some cases, this smell is caused by naturally occurring hydrogen sulfide. To problem-solve the cause, put a small amount of water in a narrow glass, step away from the sink, swirl the water around inside the glass and smell it. If the water has no odor, then the likely problem is bacteria in the sink drain. If the water does have an odor, it could be your water heater. This occurs if the hot water has been unused for a long time, the heater has been turned off for a while, or the thermostat is set too low. Contact a licensed plumber to remedy this problem. If the drain or water heater have been ruled out, and the odor is definitely coming from the tap water, contact your water utility or local health agency.

• Manganese and iron can discolor the water, stain the pipes, cause an odor, cause a sediment, etc., perhaps even make the water “unpotable”. But they do not pose a health risk, and aren’t really a “pollution” problem. [1]
• Iron and manganese are secondary contaminates in that there are no known levels in "naturally" occuring water that poses a significant health risk. Iron and manganese are fairly common problems in wells in the western US, Canada and some parts of Europe. [2]
• I suspect McCleary's taste & odor & sediment issues are attributable to elevated manganese. Manganese is considered to be a secondary contaminant; i.e.. there are aesthetic issues associated with manganese (as opposed to a health based standard). The secondary standard for manganese is 0.05 mg/l (Table 4, WAC 246-290-310(3)(a) on page 91 of the regulations manual. McCleary has 2 wells, with manganese levels that exceed the standard. The most recent sanitary survey indicates they are chlorinating and using a sequestering agent to prevent manganese from oxidizing and precipitating within the distribution system. Coliform tests have been OK. There are other methods to address manages such as oxidation and filtration, using a greensand filter, or ion exchange. The DOH Drinking Water Design Manual contains a, "Secondary Contaminant Treatment Requirements and Options" discussion that is intended to help consumers address aesthetic concerns related to manganese. [4]

When sewage pollution is a suspected source of hydrogen sulfide, the water should be tested for coliform bacteria

Iron - red brown staining on sinks and clothes

Iron is the fourth most abundant element on earth and enters water naturally as it is dissolved from the earth's crust or as iron or steel pipes corrode. As iron reacts with oxygen, it is converted into a water soluble ionic ferrous iron and then into a more stable ferric iron, which causes staining. This oxidation is another way to discribe rusting. Harmless organic compounds from decaying vegetation in water can react with iron to cause severe staining.

Iron Bacteria

Although harmless, iron bacteria can form gelatinous growths that may plug pipes or break free in slugs or dirty iron-laden water with unpleasant tastes and odors. The U.S. Environmental Protection Agency's (EPA) drinking water regulations set a recommended secondary maximum contaminant level (MCL) of 0.3 milligrams per liter (mg/L) for iron in water

Manganese - blackish staining on fixtures and laundry

Manganese enters water when dissolved from the earth's crust. Acidic waters are particularly effective at dissolving manganese and usually contain higher concentrations of the element. Manganese causes stains in much the same process as iron and is often found in conjuction with iron. As with iron, manganese reacts negetively with harmless organic compounds from decaying vegetation in water to increase staining. Since manganese is a plant nutrient, its concentrations can be naturally high in organic material- compounding the problem.

Manganese Bacteria

The EPA's drinking water regulations set a recommended secondary maximum contaminant level (MCL) of 0.05 milligrams per liter (mg/L) for manganese in water. Staining, odor and taste problems may be noticeable at this level.

References

[1] Charles Pitz, L.G., L.HG., Groundwater assessment, Washington State Department of Ecology, 3/7/2006 email to author.

[2] Cole Elliott, Parametrix, Inc., City of McCleary's engineering firm, 3/8/2006 email to author.

[3] Jeff Nelson, REHS/RS, Microbiologist, Grays Harbor County Environmental Health Division, 3/8/2006 email to author.

[4] Bill Liechty, PE, Regional Engineer, DOH Division of Environmental Health, Office of Drinking Water, Southwest Regional Operations, 3/2/2006 email to author.