Common Signs of Water Contamination (And What to Do About It)

TL;DR: Changes in smell, taste, color, or clarity can indicate water contamination. Common signs include brown or cloudy water, sulfur odors, strange tastes, and health symptoms. Whether your water comes from a private well or public source, testing is the best way to determine what’s in your water and how to treat it safely.

Clean water should look clear, taste fresh, and smell like… well, nothing. But for many New Hampshire homeowners, that’s not always the case. Whether you’re noticing a rotten egg smell in your well water or wondering if your cloudy tap water is safe to drink, it’s important to know the warning signs and take action quickly.

Let’s break down the most common signs of water contamination, what they may mean, and the steps you can take to fix the problem for good.

1. Brown Water from the Tap: Causes & Concerns

Seeing brown water from the tap is one of the most alarming and visible signs that something isn’t right. Unsightly water is often caused by:

• Rust from aging pipes, especially in older homes or towns with cast iron infrastructure
• Sediment disturbance during municipal line maintenance or hydrant flushing
• Iron or manganese contamination in well water

While brown water may not always be harmful, it can stain laundry and fixtures, taste metallic, and signal the presence of iron or corroded pipes. If you’re on a public water system or a private well, a water test is your first step.

2. Well Water Smells Like Sulfur

If your well water smells like sulfur, you’re likely dealing with hydrogen sulfide gas, a naturally occurring compound that smells like rotten eggs. It can develop from:

• Sulfur-reducing bacteria in your plumbing or well system
• Decomposing organic material underground
• Chemical reactions between magnesium and aluminum in your water heater

Hydrogen sulfide isn’t considered dangerous at typical household levels, but it’s incredibly unpleasant and may indicate bacterial activity that could lead to other problems.

What to do: If the smell is persistent, a whole-home filtration system with specialized media can treat sulfur odors and improve water quality across your home.

3. Cloudy or Milky Water

Cloudy water, sometimes described as “milky” or full of tiny bubbles, is usually caused by air trapped in the pipes. If the cloudiness fades after the water sits for a few moments, it’s likely harmless. But if it stays cloudy or you notice floating particles, the issue could be:

• Sediment or sand in well water
• Organic matter or bacterial growth
• High levels of calcium or magnesium (hard water)

What to do: Start with a water test to determine whether the cloudiness is caused by air, minerals, or contaminants. Depending on the cause, sediment filters or water softeners may be recommended.

4. Metallic or Bitter Taste

Does your water taste like metal, pennies, or have a chemical aftertaste? This could be a result of:

• Iron or copper leaching from pipes
• Zinc or manganese in groundwater
• Excessive disinfectants like chlorine or chloramine

While metallic-tasting water isn’t always dangerous, it could be a sign of pipe corrosion or elevated heavy metal levels, especially if your home has older plumbing.

What to do: A certified point-of-entry filtration system can reduce metals and improve taste. For more serious concerns like lead or arsenic, reverse osmosis filtration at the tap may be needed.

5. Blue or Green Stains in Sinks and Tubs

Blue-green stains from water are a cosmetic nuisance and one of the telltale signs of contamination from copper corrosion. This usually occurs when water is too acidic (low pH), causing it to eat away at copper pipes and fixtures.

Over time, exposure to high levels of copper can lead to stomach problems and other health issues, especially in children.

What to do: Have your water’s pH tested. Acid-neutralizing filters or treatment systems that stabilize pH levels can prevent future corrosion and staining.

6. Bad Smells or Unusual Odors

Apart from sulfur, other water odors may point to different contamination sources:

• Musty or earthy smell often a sign of organic matter or algae in the water supply
• Bleach or pool-like odor high levels of chlorine
• Fishy or metallic odors could indicate decaying organic matter or metal contaminants

How to tell if tap water is safe: Odor alone isn’t always a definitive test, but it’s a good reason to investigate further. Water testing can reveal what’s behind the smell and whether it poses a risk.

7. Family Health Concerns

If your household is experiencing unexplained health symptoms, especially stomach upset, skin irritation, or recurring illness, it’s worth considering your water quality as a possible factor. Low levels of bacteria, heavy metals, or disinfection byproducts may cause chronic symptoms that are difficult to trace.

What to do: Get your water professionally tested for microbiological, chemical, and physical contaminants. A custom filtration system can be tailored to address what’s found in your specific water supply.

Final Thoughts: What to Do if You Suspect Water Contamination

No one wants to guess whether their water is safe. If you’re seeing, smelling, or tasting any of the warning signs above, the best course of action is:

• Get a water test from a trusted local expert
• Identify your source public water or private well
• Install the right solution based on what’s found

At NH Tap, we specialize in identifying and treating water quality issues across New Hampshire. Whether your concern is brown water from the tap, a sulfur smell in your well, or you’re simply unsure how to tell if your tap water is safe, we’re here to help.