Questions about Colored Water

Learn more about colored water

What Could be Causing Colored Water at My Tap?

In general, there are two causes of discoloration.  The first possibility is that it is coming from the customer’s internal plumbing.  The second possibility is that it is coming from the provider’s water distribution system.  Investigating the location of the problem can help determine the cause.  If the colored water is present at taps inside the house, but is not evident at the outside hose bib, the issue is most likely related to internal plumbing.

What are the Main Reasons for colored water related to internal plumbing?

• The customer’s plumbing consists of galvanized (steel) pipes which are rusting on the inside.
• The customer’s hot water heater is rusting or has not been flushed for several months. 
• Sediments have built up in the internal pipes over a period of time and sudden heavy usage stirs these sediments up.

My water appears white, MILKY or cloudy.  Is this safe to drink?

If your tap water has a slightly white, milky or cloudy appearance, you’re probably experiencing an interesting but harmless phenomenon known as “entrained air.” When drinking water wells are used to deliver water in a service area, microbubbles of air can be introduced into the water causing what is referred to as entrained air.  These microbubbles are harmless, and if you let the water settle for 60 seconds you will see this cloudiness dissipate.

Where are the main reasons for colored water related to the provider’s water distribution system?

• There are a number of issues that can cause water of varying colors and shades —two of the most common causes are iron and manganese. 

• Iron tends to add a rusty, reddish-brown (or sometimes yellow) color to water.
• Higher levels of manganese add a darker reddish color to water. 

• Your water may contain a combination of iron and manganese. 

Where do Iron and Manganese in My Drinking Water Come From?

Iron and manganese are naturally present in the water Zone 7 treats and delivers to its retailer water systems and direct customers.  Zone 7 regularly tests both source (untreated) and delivered (treated) drinking water supplies.  The results of delivered water testing is included in the annual Consumer Confidence Report that is available on the Zone 7 Water Agency website. 

What else can Cause Higher Levels of Iron and Manganese?

Disturbances such as flushing or a main break in Zone 7’s transmission system or one of the retailer’s distribution systems can lead to scouring within pipes and result in short periods of high iron and/or manganese.  These events are typically very brief and last only a few days.

How Dangerous are Iron and Manganese in my Drinking Water?

The United States Environmental Protection Agency (EPA) classifies iron and manganese as secondary contaminants. Secondary contaminants are substances that can alter the taste, odor and color of drinking water. They can also have impacts on the structure or function of the water system within the home, the water well itself or, stain plumbing fixtures, dishware, and laundry. Generally, secondary contaminants do not pose significant health risk.

Is Zone 7 Taking Any Steps to Remove Iron and Manganese in My Water?

Zone 7 utilizes both chlorine and ozone at both surface water treatment plants as a means of disinfection.  In addition to disinfection, chlorine and ozone oxidizes iron and manganese into a form that is more easily removed by the treatment process.  While not all of the iron and manganese present is removed, it can be significantly reduced.