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Water-Quality

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1. What should I do once the boil water advisory is lifted in my area?

Residents are advised to "flush" their water following the lifting of the boil water advisory, to clear plumbing of potentially contaminated water. Please follow these guidelines:

Clean aerators: (aerators are the screens at the end of the faucets, they reduce the amount of water that comes out of the faucet and control the flow. 

Flush cold water faucets: 5 minutes with cold water.

Flush hot water faucets: To clear hot-water pipes and water heater, flush the hot water line for a minimum of 15 minutes for a typical household 40-gallon hot-water tank, 30 minutes for an 80-gallon hot water tank or larger. 

Water Heaters: run hot water from all faucets until water runs cold. Second option is to drain the water heater using spigot/release on the bottom of heater.

Flush showers: 5 minutes of a mix of hot and cold water

Toilets: flush and clean each toilet.

Dish Washers: If your machine has a sanitize cycle, run 1 cycle

Outdoor Spigots: 5 minutes, disconnect hose first.

Refrigerator Water Dispenser: flush for 5 minutes or at least 1 quart of water.

Faucet/Fridge Water Filters: consider replacing filter per manufacturer recommendation.

In-Line Water Filter: consider replacing filter per manufacturer recommendation.

Ice Makers: Discard about three batches of ice from the ice maker and sanitize the ice bin.

Water Softeners: cycle water softener per manufacturer recommendation.

Humidifiers: Discard any water used in humidifiers, Continuous Positive Airway Pressure (CPAP), oral, medical, or health care devices, and rinse the device with clean water.

2. Is it safe to do laundry during a boil water advisory?

It is safe to wash clothes as usual. 

3. How long will the boil water advisory remain in effect?

Each boil water advisory is different, making it impossible to predict how long the boil water advisory will remain in effect. The minimum duration of a boil water advisory is 48 hours. It will not be lifted until testing shows that the water meets public health standards. Boil water advisories are lifted when the water is considered safe and no longer poses a threat to public health. 

4. I have heard that you need to boil water longer than 1 minute, is that true?

For elevations below 6,500 ft. one minute is sufficient. Elevations above 6,500 ft. it is recommended that you boil water for three minutes. This is because as altitude increases and atmospheric pressure decreases, the boiling point of water decreases. To compensate for the lower boiling point of water at higher elevations, the boiling time must be increased. 

5. How do I care for my garden and houseplants during a boil water advisory?

You can use tap water for household plants and gardens. If growing herbs or edible plants, be sure to rinse with boiled or bottled water before eating.

6. Food preparation during a boil water advisory?

During a boil water advisory, wash fruits and vegetables with boiled or bottled water. Use boiled or bottled water for infant formula, Use boiled or bottled water to make beverages such as coffee, tea, or juice. 

7. How do I care for my pets during a boil water advisory?

Give pets bottled or boiled water that has been cooled. Do not use water from any appliance connected to your water line, such as ice and water from a refrigerator.

8. Is it safe to wash dishes during a boil water advisory?

If possible, use disposable plates, cups, and utensils during a boil water advisory. Household dishwashers generally are safe to use if the water reaches a final rinse temperature of at least 160 degrees F. or the dishwasher has a sanitizing cycle. Sanitize all baby bottles. 

To wash dishes by hand:

1. Wash and rinse the dishes as you normally would using hot water.

2. In a separate basin, add 1 teaspoon of unscented household liquid bleach for each gallon of warm water.

3. Soak the rinsed dishes in the water for at least one minute.

4. Let the dishes air dry completely before using them.

9. Is it safe to bath and/or shower during a boil water advisory?

Adults may continue to shower, exercising caution to ensure no water is swallowed. Use caution when bathing babies and young children. Consider giving them a sponge bath to reduce the chance of them swallowing water. Open cuts or wounds should be covered to ensure no exposure to water. 

10. Where does Maui water come from?

If you live in Upcountry Maui, your water is surface water from the streams in East Maui. It's treated and disinfected at one of our three water treatment facilities (Kamole, Piiholo, Olinda) before it's delivered to your home. Customers in Haiku get their water from the Haiku or Kaupakalua wells and/or the Kamole WTF. For Central Maui (Kahului, Wailuku, Waihee, Maalaea, Kihei, and Paia) your water is groundwater from the Iao Aquifer under the West Maui Mountains. That water is naturally filtered by lava rocks, disinfected, and sent to your home. A small amount of filtered surface water is added to the Central System at the Iao WTF. Hana and Molokai also use groundwater. Lahaina has a mix of surface water and groundwater. The water treatment facilities for West Maui are located above Lahainaluna School and near the Kapalua Airport.

11. Is Maui County's drinking water really safe?

Yes. Maui water meets or is better than all standards set by the federal and state governments. The U.S. Environmental Protection Agency (EPA) and the Hawaii State Department of Health require the Department of Water Supply to test the water regularly to make sure it's safe. Take a look at our Water Quality Reports. They tell you about the source of your water, show any detected contaminants or elements in the water and ensure you that your drinking water meets all safe drinking water standards. To ensure that your tap water is safe to drink, the EPA sets maximum limits on the amount of certain contaminants in public water systems. If you are concerned about your water quality, you may request more information or a water quality test. Just give the DWS Laboratory a call at 270-7550. DWS Water Quality Reports

12. What causes occasional taste and odor changes in Maui water?

All water has its own unique taste and odor characteristics. Maui, like many other water suppliers, occasionally experiences taste and odor changes. Based on the different minerals found in minute quantities in certain aquifers, the taste of the water may vary. Taste and odor problems can also come from new or old pipelines, plumbing fixtures, or changes in water quality. Customers may notice changes during severe storms with heavy rain, when reservoir water levels are low, or during temperature changes and hot weather. These changes do not affect the safety of the water. Flushing the water can solve this problem. As a general practice, water should be flushed in the morning or when not used for 6 to 8 hours.

13. Why is chlorine added to the water?

Chlorine is added to the water as a disinfectant. It is used to protect you from any harmful bacteria that may be present in the water. If you do not like the taste of chlorine, put some water in a container and let it sit overnight in the refrigerator.

14. Why does my water look milky sometimes?

Milky water is usually due to air bubbles trapped in the pipe lines. Let the water stand in a glass for several minutes. The water becomes clear from the bottom up if air is the cause. This water is safe to drink. Flush all the taps in your home to clear the lines.

15. Do I have hard or soft water?

Hardness is measured in mg/L (milligrams per liter). Any reading over 75 mg/L is considered as hard water. Surface water is generally soft water. Makawao, Pukalani, Lower Kula, and Upper Kula have soft water between 17 to 69 mg/L. Ground (well) water here on Maui is usually 51 to 171 mg/L.

16. What is the pH of my water?

The pH of water in the various districts on Maui are:
Central: 7.3 - 7.9
Makawao: 7.6 - 9.1
Lahaina: 7.8 - 8.2
Lower Kula: 7.9 - 9.0
Upper Kula: 7.2 - 9.7
Molokai: 7.2 - 7.9
Hana: 7.5 - 7.9

17. How much water does an average residential customer use in a month?

For 1998, the average person used about 250 gallons per day. That number is usually higher during lawn watering periods.

18. Why do we have droughts Upcountry?

Because the water for the Upcountry area is from streams. When it stops raining, the stream flow stops, too. Droughts are a part of the regular climate cycle, and occur every 3 to 4 years. The Department of Water Supply is currently endeavoring to mitigate the effects caused when we experience a drought by the integration of ground water sources from East Maui as an alternative supply. Additionally the Department is in the process of investigating the feasibility of constructing additional storage reservoirs to meet peak demand during droughts. These reservoirs are very expensive as well as environmentally controversial. The County of Maui State Legislative package for this year contains two million dollars for this purpose. Without State funds, we would not have the storage that we currently have. Check out the drought page for updates.
Current Upcountry Water Levels

19. Where can I get more information about lead in Upcountry residential plumbing and what is the DWS doing about it?

Please see the lead page.
More information on lead ...

20. I live in Upper Kula. What are chloramines and how can they affect me?

Please see the chloramines page.
Chloramines

21. I recall receiving notices about the water quality in Upcountry Maui, but I haven't seen one in a long time. What happened to those notices?

Since 1999, the water supplied to the Upcountry area has been in compliance with EPA and Hawaii State Department of Health regulations. The last notice was mailed out in March 1999. See the Water Quality Report page and go the Upcountry section to see current water quality in that area.
DWS Water Quality Reports

22. How do I find out information about wastewater reuse/reclamation (recycled water)?

The Department of Environmental Management is responsible for wastewater reuse/reclamation (recycled water) for the County of Maui. For more information, you may call the Wastewater Reclamation Division at (808) 270-7417 and request to talk to the Recycled Water Coordinator.

• Dept. of Environmental Management - Wastewater

Dept. of Environmental Management - Wastewater

23. How do I find out more information about wastewater?

The Department Environmental Management is responsible for wastewater in the County of Maui. This Department is in charge of all sewer issues, wastewater and pumping facilities, wastewater collection lines, and cesspool pumping. Please call the Wastewater Reclamation Division at 270-7417 for more information about wastewater.
Dept. of Environmental Management - Wastewater