A taste change does not automatically mean the water is unsafe, but taste also cannot prove that water is safe. Find the pattern before buying a filter or adding treatment.
See whether it happens at one faucet
If only one fixture tastes odd, clean the aerator and run cold water briefly. A local supply line, aerator, or section of plumbing can affect taste. If every faucet is affected, look more broadly at household plumbing or the utility supply.
Compare cold and hot water
If the taste appears only in hot water, the water heater and hot-water piping become more relevant. For drinking and cooking, draw cold tap water and heat it afterward.
Disinfectant and utility work can cause temporary changes
Water systems may adjust disinfection or perform flushing and repairs that temporarily change taste or odor. Check utility notices if the change appeared suddenly or neighbors notice it too.
Do not use taste to rule out contaminants
The U.S. Environmental Protection Agency distinguishes aesthetic issues from health contaminants that may have no taste or odor. Lead, for example, cannot be ruled out by tasting water. Older plumbing, recent construction, an official advisory, or a specific concern is a reason to seek utility information or accredited testing.
A filter should match the problem
Identify what you want to reduce and choose a filter certified for that contaminant. Replace cartridges on schedule; a neglected filter can create its own taste and flow problems.
A new persistent taste accompanied by discoloration, particles, or a utility advisory deserves investigation. A taste that appears after long stagnation and improves after briefly running cold water points more toward local plumbing.
Sources
- U.S. Environmental Protection Agency — Secondary Drinking Water Standards — Taste, odor, color, iron, copper, and other aesthetic drinking-water issues.
- U.S. Environmental Protection Agency — Basic Information about Lead in Drinking Water — Lead in drinking water, testing, and why taste is not a reliable safety test.