Q:  What is the pH of our water?  
      pH refers to the acidity or alkalinity of water and is expressed in terms of a
      numerical scale from 0 to 14. Seven (7) on this scale means that the water is
      neither acidic  nor alkaline.  For values less than 7, the smaller the number, the
      more acidic it is. For values greater than 7, the larger the number, the more
      alkaline it is. 

      The pH balance of the drinking water served by the Board of Water Supply
      (BWS) occurs naturally in the 7 to 8 range. This means that the water ranges
      from being neither acidic nor alkaline (pH 7) to being only slightly alkaline (pH 8). 

Q:   What about lead? Is there lead in our water supply? 
       Our laboratory has conducted a series of tests for lead in our municipal water
       supply. Samples were taken from BWS sources, within the distribution system
       in the community, and from consumers' household taps. 

       Based on these tests, no lead was found in any of the municipal water supplies
       served to Oahu's residents. 

Q:    Does the BWS conduct free tap water tests when a complaint or
       request is made? 
       The BWS conducts tests at the tap only when specific water complaints,
       such as taste, discoloration, odor, or presence of particulate matter, are
       received from our customers. 

       If customers are curious about what's in their water, they should contact a
       private laboratory to have a sample analyzed. These laboratories are listed
       in the telephone directories under Laboratories-Analytical. 

Q:    Do customers need to purchase water filter units for their homes?
       Does the BWS offer consumer guides to home filtration sytems? 
       The municipal water supply served to Oahu's residents is safe to drink and
       use, and does not require treatment by a home filtration unit. 

       We do not offer any information or consumer guides on filtration
       systems. Customers should conduct their own research about water filter 
       products when making a decision on whether to purchase such a system or
       device. 

       In incidents of water quality complaints, the BWS will not test water that has
       been altered by the installation of a filtration system. The customer may need
       to contact a private laboratory to have a sample analyzed, or check with the
       product representative or manufacturer for assistance. 

Q:    Does the Board of Water Supply treat water? 
       Yes, the BWS treats water in accordance with all federal and state drinking 
       water regulations.  Currently, the BWS treats drinking water with chlorine and
       in certain areas of Oahu the water is treated with granular activated carbon
       (GAC).

Q:   Is all of our drinking water on Oahu chlorinated?
       Yes, almost all of the water pumped into the BWS water distribution system is
       chlorinated. Because our distribution system is interconnected, waters from 
       chlorinated sources can mix with unchlorinated supplies. Small amounts of 
       chlorine in the water may be found most everywhere on Oahu. Concentrations
       can range from zero to 0.15 milligrams per liter (ppm) of chlorine throughout the
       water system. Since excessive amounts of chlorine can affect the taste and
       odor of drinking water, the Board adds only what is needed to keep disease-
       causing bacteria from contaminating our water supply.

       If you experience a strong chlorine smell or taste in your water, contact the
       Board of Water Supply's Microbiological Laboratory at (808) 748-5850. 

Q:   Is fluoride added to the drinking water here on O'ahu?
       The BWS does not add fluoride to the municipal water supply. 

       However, Federal regulations require that all military installations add 
       both fluoride and chlorine to their water supplies regardless of water quality. 

Q:   How can I find out what is in my water?
       Water quality test results are shared with our customers in our annual water
       quality report or Consumer Confidence Report (CCR), as required by the EPA. 
       The CCR, along with an accompanying water quality informational pamphlet,
       will be mailed to you by July 1 each year. The CCR identifies where your water
       comes from, what regulated contaminants were found, how those levels 
       compare to the standards for safe drinking water, and describes any treatment
       processes used. To get your water quality report, or the water quality
       informational pamphlet, click here.  

Q:   Does BWS test my water?
       Yes.  Every year, the BWS and the DOH conduct thousands of tests on the
       water source and distribution system to ensure that the water you receive is 
       safe to drink. These tests check for more than 100 different types of
       contaminants, as required by the EPA. All final test results show the BWS is in
       full compliance with state and federal standards for safe drinking water. If the
       water quality tests conducted did not meet state or federal safe drinking water 
       standards, the BWS would be required by law to immediately notify impacted
       customers and more importantly, the BWS would stop serving that water until
       it met all federal and state drinking water regulations.

Q:   What are the Drinking Water Standards? 
       The Safe Drinking Water Act (SDWA) is the federal law that governs the quality
       of drinking water in the United States.  Under the SDWA, the U.S. Environmental
       Protection Agency (EPA) sets standards for drinking water quality and oversees
       state compliance with those standards. 

       In Hawaii, the State Department of Health (DOH) is responsible for ensuring that
       all public and private drinking water suppliers comply with state and federal
       drinking water standards. The responsibility rests with each water
       supplier to comply with the standards. The DOH and EPA is responsible to
       monitor and enforce these regulations. 

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