What's on Tap: Alkalinity in Drinking Water

WHAT IS ALKALINITY?

Often found on water contaminant lists with things like e. Coli and sediment, alkalinity plays a much different role in water. Defined by the Water Research Center as "water's capacity to resist changes in pH that would make the water more acidic", alkalinity protects the water and its life forms from sudden shifts in pH. If any changes are made to the water that could raise or lower the pH value, alkalinity acts as a buffer. Alkalinity is often confused with pH because water with a pH level above 7 is commonly referred to as alkaline. But alkalinity is not the same as pH because water does not have to be strongly basic (pH above 7) to have a high alkalinity level. Alkalinity is related to pH because higher levels of alkalinity help stabilize the pH level.

HOW ALKALINITY GETS INTO OUR WATER

The alkalinity of water depends on the types of soil and bedrock that it travels through, as it moves from small springs toward larger bodies of water. When water passes through rocks containing carbonate, bicarbonate and hydroxide compounds, it develops alkalinity. Geographic areas that have a lot of limestone will have alkaline water because limestone is rich in carbonates.

SYMPTOMS OF ALKALINITY: WHAT TO LOOK FOR

Whether high or low, alkalinity levels do not have serious or adverse health effects. There are, however, noticeable signs of high or low levels. High levels of alkalinity in water can result in a soda-like taste and dry skin, as well it can cause scaling in pipes and fixtures. Low levels can be irritating to eyes, and its corrosive effect can damage pipes and water systems. Though generally safe for consumption, it's common for city water systems to maintain a balanced level of alkalinity because low levels can damage pipes and equipment.

EFFECTS OF ALKALINITY

If the alkalinity is too low, the ability of your water to resist pH changes decreases. This means that the pH will yo-yo up and down, changing from acidic to basic rapidly.

TESTING FOR ALKALINITY

If you want to learn about the alkalinity level of your home's water, there are three steps you can take to verify the quality and safety of your drinking water:

• Consult your water supplier for reports on their water testing
• Test your home's water independently using a water test kit. Just make sure the kit you purchase will test for alkalinity.

ALKALINITY LEVELS AND STANDARDS

Alkalinity is not regulated as a contaminant. Since low alkalinity can cause corrosion problems, it's a good idea to test your home's water if you're seeing signs of corrosion.

SOLUTIONS AND WATER TREATMENT

There are a few different alkalinity filtration options for both drinking water and whole house filtration. A difficult contaminant to remove, it typically requires at least two or three filtration stages before your water can be considered "clear" of alkalinity.

WHEN TO REPLACE THE FILTER

Regular replacement of the filter and/or cartridge is critical to maintaining their effectiveness and reducing bacterial contamination. An overused or out-of-date filter can become dangerous because the filter will no longer trap contaminants, allowing them to leach back into your water. For the safety of you and your loved ones, it's important not to put off replacement too long. There are four effective ways of knowing when it's time to replace your water filter:

1. Follow the manufacturer's recommendations. Their specified replacement timing will err on the side of caution so you can be assured that your water quality will always be safe.
2. Measure usage. Install a filter measurement meter or filter monitor that connects to the incoming water line that feeds the filter system and measures the number of gallons that pass through. Then using the manufacturer's recommended usage limit, program the monitor to alert you when you've reached the allowed number of gallons. You'll know exactly when it's time to replace the filter.
3. Read your water bill. If your home is supplied with municipal water, your water bill will tell you exactly how much water is used monthly. Compare your actual usage to the manufacturer's recommendation and plan the replacement accordingly.
4. Monitor manually. If you have non-municipal water, the most cost-effective method is to monitor your filter manually either with your palate or a water testing kit. Start with routine water tests that look for lead, microorganisms and other contaminants to verify whether your filters are still removing them. For drinking water systems, simply fill a glass with water and check the flavor yourself. You'll be able to see or taste when the filter is exhausted and no longer purifying your water because the water flavor will be unpleasant.

GET ADVICE

For answers to alkalinity-related questions, recommendations on the best filter for your home or general drinking water questions, contact us.