Why does Walmart put sodium bicarbonate in their water?

January 11, 2026 •

3 min read

According to the ingredients listed on its label, Walmart's Great Value Purified Drinking Water contains added minerals, including sodium bicarbonate. The primary reason why Walmart puts sodium bicarbonate in their water is to improve its taste and balance the pH after the purification process has stripped it of all natural minerals.

Quick Summary

Walmart adds sodium bicarbonate to its purified water to achieve a balanced pH level and enhance the flavor. This mineral supplementation, common in the bottled water industry, addresses the flat taste that can result from purification processes like reverse osmosis.

Key Points

Purpose: Walmart adds sodium bicarbonate and other minerals to its purified water to improve taste and adjust pH levels.
Purification Effect: Extensive purification processes, like reverse osmosis, strip water of all minerals, resulting in a flat and unappealing taste.
pH Balance: Sodium bicarbonate acts as a buffer, raising the water's pH from slightly acidic to a neutral or slightly alkaline state, which is vital for consistency.
Industry Standard: The practice of adding minerals back into purified water for taste is a common procedure across the bottled water industry.
Source vs. Purity: Some of Walmart’s water starts from municipal sources but undergoes rigorous, multi-stage purification that transforms it into a consistently clean and safe product.
Taste Preference: The small amount of added minerals creates the crisp, refreshing taste that consumers have come to expect from bottled water.

The Purification Process and Its Impact on Taste

Walmart's Great Value water is labeled as 'purified water'. This means the water undergoes a rigorous purification process, often involving reverse osmosis, distillation, or deionization, to remove contaminants, chemicals, and dissolved solids. While this makes the water exceptionally clean, it also strips out all naturally occurring minerals, leaving it with a very flat or bland taste. The mineral content of water, measured as total dissolved solids (TDS), is crucial for its flavor and mouthfeel. To make the water more palatable for consumers, manufacturers must reintroduce select minerals.

The Role of Sodium Bicarbonate

Sodium bicarbonate, commonly known as baking soda, serves as a key mineral in this remineralization process. The purified water, without any minerals, tends to have a slightly acidic pH level. Adding a small amount of sodium bicarbonate serves as a buffering agent to increase the water's alkalinity, raising its pH to a more neutral or slightly alkaline range. This process is vital for several reasons:

Improved Taste: The addition of sodium bicarbonate and other minerals like calcium chloride gives the water a clean, crisp, and refreshing taste that many consumers prefer over the flavorless profile of demineralized water.
pH Balancing: Stabilizing the pH prevents the water from becoming too acidic, which can potentially affect the taste or interact with the plastic bottle over time.
Safe and Simple: Sodium bicarbonate is a safe and common food additive, widely used for similar purposes in various products.

Great Value Water: Ingredient Transparency

Walmart lists the ingredients of its Great Value purified water right on the label, typically stating, 'Purified Water, Calcium Chloride, Sodium Bicarbonate'. This transparency is standard practice and allows consumers to know exactly what is in their water. The process is a form of consumer-driven modification, ensuring the end product meets taste expectations that unadulterated purified water would not. This practice is common across the entire bottled water industry, not just at Walmart.

Addressing the Source of the Water

Some consumers are surprised to learn that private-label bottled water, including some of Walmart's, may be sourced from municipal tap water. This does not mean the water is simply bottled tap water. It is a common misconception. Instead, the water is purchased from a municipal source and then put through the extensive, multi-stage purification process (which can include reverse osmosis, UV sterilization, and filtration) before remineralization and bottling. This rigorous treatment ensures a consistent, high-quality product, regardless of the initial water source.

The Alkaline Water Connection

While some brands explicitly market their water as 'alkaline' and tout health benefits, Walmart's addition of sodium bicarbonate primarily serves a functional purpose related to taste and pH stability, not as a marketing gimmick. Although the added sodium bicarbonate does make the water slightly alkaline, this is a byproduct of the taste-improvement process, not the sole objective. The purported health benefits of drinking alkaline water are largely unproven by scientific evidence.

Comparison of Bottled Water Types

To clarify the differences, here is a comparison table outlining the key characteristics of various bottled water types.


Feature	Purified Water	Spring Water	Alkaline Water	Mineral Water
Source	Municipal or other sources	Natural, underground spring	Any source, but pH modified	Natural, underground spring source
Treatment	Extensive filtration (RO, UV), then remineralized	Minimal filtration, no additional processing	Purified, then minerals added or ionized	Minimal filtration, no minerals added
Mineral Content	Added minerals (e.g., sodium bicarbonate, calcium chloride)	Naturally occurring minerals from spring	Higher mineral content, especially alkaline minerals	Higher natural mineral content, must contain specific quantities
Taste Profile	Consistent, clean, and refreshing	Varies depending on source of spring	Slightly bitter or different flavor due to pH and minerals	Varies depending on mineral composition

Conclusion

Ultimately, the practice of why Walmart puts sodium bicarbonate in their water is a strategic and standardized procedure within the purified bottled water industry. The process corrects the bland flavor and acidic tendencies created during advanced purification. By adding back small, safe amounts of minerals like sodium bicarbonate and calcium chloride, Walmart ensures its Great Value purified water offers a consistent, crisp taste that consumers expect. This is a matter of product quality and consumer preference, not a health claim. Consumers who prefer purified water over spring or mineral water can be confident that the added ingredients serve a clear, quality-control purpose. For more information on the water purification process, consumers can refer to industry resources that detail the processes and regulations involved.

Frequently Asked Questions

Yes, the small amount of sodium bicarbonate added to bottled water for taste and pH balancing is considered safe for consumption. It is a common food additive and is FDA-approved for this purpose.

Tap water contains a varying profile of natural minerals that give it a specific taste. Walmart's purified water has had all minerals removed and then had a precise mix of minerals, including sodium bicarbonate and calcium chloride, added back for a consistent, clean taste.

While the addition of sodium bicarbonate does make the water slightly alkaline, Walmart's primary purpose is taste and pH balance, not to market it as a specific 'alkaline water' product. True alkaline water often uses different methods to achieve a higher pH.

Some claims about the health benefits of drinking alkaline water, including reducing acid reflux or inflammation, lack robust scientific evidence. For bottled water, the tiny quantity of sodium bicarbonate is mainly for taste.

Not all of Walmart's bottled water is from a natural spring. The 'Great Value Purified Drinking Water' can be sourced from municipal water supplies and then extensively purified and remineralized. Walmart also offers 'Great Value Spring Water,' which is sourced differently.

Purified water, like Walmart's Great Value, has been processed to remove all contaminants and minerals before being remineralized for taste. Spring water is naturally filtered underground and contains naturally occurring minerals, with minimal processing.

In addition to sodium bicarbonate, Walmart's Great Value Purified Drinking Water often lists calcium chloride as another added mineral. These are added together to enhance the overall flavor and body of the purified water.