-a series of SIX VIDEOS about safe and effective water systems

Tape #2

Red Water

This VIEWER REFERENCE GUIDEis yours to keep!
DO NOT RETURN IT when you return the tape.

MRC Catalog #75703

What causes red (or yellow) water?

MINERAL IRON
comes from iron-bearing soil or rock through which groundwater flows. May also be caused by corrosion of iron pipe.

IRON BACTERIA
non disease-causing bacteria that form iron-laden slime on the interior of plumbing systems.

What are some symptoms of mineral iron and iron bacteria?

Water from the tap is red or yellow.
Water from the tap is clear but turns red or yellow after several minutes of exposure to air-often called "clear water" iron.
There are red stains on fixtures or laundry.
The water softener becomes plugged.
Water has a metallic flavor.
A red, slimy coating inside pipes and toilet tank.

What's the first step in dealing with red water?

Test for mineral iron and iron bacteria to see if one or both are present.
A mineral iron sample may be drawn from any tap that deliversuntreated water from the well.

Iron bacteria coat the INSIDE SURFACES of the plumbing system. The interior of the toilet tank is a good location for obtaining a sample.
1-Look for red residue below the waterline inside the toilet tank.
2-Scrape some residue into a sample bottle; fill with water, and send to the lab.

What can I do about mineral iron in my water?

This depends on the type and amount of mineral iron present.
Two types of mineral iron are common in Iowa well water. Water containing dissolved iron (also called "clear water" iron) has little or no color when it first comes from the tap. After exposure to air for several minutes, dissolved iron reacts with oxygen to form tiny particles of "oxidized" iron, giving the water a yellow or reddish color.

An ion exchange water softener can remove moderate levels of dissolvediron-usually 5 milligrams per liter or less. Be sure to compare the maximum iron levels recommended by the softener manufacturer with the amount of iron in your water before you purchase a unit. (Note: Oxidized iron, or levels of dissolved iron exceeding the manufacturer's recommendations, will cause a softener to become plugged.

For oxidized iron, or dissolved iron levels exceeding softener manufacturer's recommendations, an oxidizing filter (often called an "iron filter") can be used. Oxidizing filters contain a special sand which must be treated occasionally with potassium permanganate to maintain iron removal capability.

For very high levels of dissolved or oxidized iron (consult manufacturer's recommendations), chemical oxidation-using an oxidizing chemical such as chlorine-followed by a sand filter to trap and remove the oxidized iron, will give best results.

What can I do about iron bacteria in my water system?

Start with shock-chlorination;
places a high concentration of chlorine bleach in well and plumbing system to kill iron bacteria.

SEE-Extension publication Pm-899, Shock Chlorinating Small Water Systems for details.

NOTE-It's nearly impossible to kill ALL of the iron bacteria in your system; so they WILL grow back eventually. Be prepared to repeat the treatment from time to time.

If iron bacteria regrowth is rapid, repeated shock chlorination becomes time consuming. Continuous application of low levels of chlorine may be less work and more effective. An automatic liquid chlorine injector pump, or a dispenser that drops chlorine pellets into the well are common choices.

 NOTE-Chlorine rapidly changes clear water iron into oxidized (colored) iron. You may need a filter to remove oxidized iron if continuous chlorination is used to control iron bacteria.

How can I keep my iron removal equipment in good working order?

If using a softener to remove dissolved iron, periodic application of a resin bed cleaner can help prevent iron accumulation and eventual plugging.

Oxidizing filters MUST be treated regularly with potassium permanganate to maintain iron removal capacity.

Softeners, oxidizing filters, and plain sand filters MUST be backwashed regularly to keep them clean. Make sure your well and pump can supply water at the filter manufacturer's recommended backwash rates. Inadequate backflushing can lead to plugging of the filter.

-other sources of information-

Your local county or community environmental/health sanitarian

Iowa Department of Public Health, Lucas State Office Building, Des Moines, IA 50319-0075 (515-242-6340)

University of lowa Hygienic Laboratory. Oakdale Hall, lowa City, IA 52242 (319-335-4500

Geological Survey Bureau, lowa Department of Natural Resources, 123 North Capitol, lowa City IA 52242 (319-335-1575)

National Sanitation Foundation, 3475 Plymouth Rd., P.O. O. Box 1468, Ann Arbor, Ml 48106 (313-769-8010)

Water QualityAssociation, 4151 Naperville Rd., Lisle, IL 60532 (708-505-0160)

This material is based upon work supported by the U.S. Department of Agriculture,

Extension Service, under project number 89-EWQI-1-9108

Ames, lowa 50011

AE 3059 July 1991

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