What to Include in Your Water Quality Checklist

Written by Craig "The Water Guy" Phillips

Your water quality checklist should include annual tests for total coliform bacteria, nitrates, TDS, pH, iron, and manganese. You'll also want to inspect your wellhead every spring, replace filters on schedule, and test immediately after flooding, repairs, or any sign of contamination. Safe limits matter too—zero bacteria, nitrates below 10 mg/L, arsenic under 10 µg/L. Understanding what these numbers actually mean for your family's health is where things get really important.

Key Takeaways

• Test annually for total coliform bacteria, nitrate, TDS, pH, iron, and manganese to catch contamination and corrosion trends early.
• Include immediate retesting triggers such as flooding, septic failure, well repairs, or any positive bacterial test result.
• Track safety thresholds: zero bacteria, nitrate below 10 mg/L, arsenic below 10 µg/L, and no acceptable lead level.
• Schedule regular wellhead inspections each spring and replace filters per manufacturer guidelines, typically every 3–24 months.
• Document all test results, inspections, and treatments over time to identify patterns and support certified lab comparisons.

Test Your Private Well Water for These 4 Contaminants First

If you own a private well, you're solely responsible for keeping your water safe—no municipal utility is looking out for you. So where do you start?

Test annually for these four contaminants: total coliform bacteria, nitrate, total dissolved solids (TDS), and pH.

A positive coliform result signals possible fecal contamination and triggers immediate E. coli follow-up testing.

Nitrate levels at or above 10 mg/L (NO3–N) can cause methemoglobinemia in infants.

TDS above 1,500 mg/L degrades taste and causes scaling.

And abnormal pH accelerates pipe corrosion, leaching metals like lead into your water.

Always use a state-certified lab, collect bacterial samples in sterile containers, and deliver them within 36 hours. Precision here isn't optional—it's everything.

Safe Levels for Bacteria, Nitrates, Arsenic, & Lead in Well Water

Once you know which contaminants to test for, the next question is just as important: what do the numbers actually mean?

For bacteria, the answer is binary — zero total coliform, zero E. coli. Any detection triggers follow-up testing or immediate action.

Nitrates should stay below 10 mg/L as nitrogen; exceed that, and infants face serious methemoglobinemia risk.

Arsenic needs to read under 10 µg/L — anything higher carries long-term cancer risks requiring treatment.

Lead is different. There's no safe level, period. Even trace detection demands a response: corrosion control, certified point-of-use filters, or plumbing replacement.

Notice the pattern — some contaminants have thresholds, one has none. Understanding that distinction helps you move from raw test results to smart, confident decisions about your water.

When to Test Your Well Water, Inspect Pipes, & Replace Filters

Testing well water, inspecting pipes, and replacing filters aren't one-time events — they're ongoing commitments tied to specific triggers and timelines. Miss a cycle, and contamination can go undetected for months.

Task	Routine Schedule	Immediate Triggers
Water testing	Annually (bacteria, nitrates, TDS, pH)	Flooding, septic failure, well repairs
Wellhead inspection	Each spring	Cracks, open seals, damaged caps
Filter replacement	Every 3–24 months by type	Reduced flow, visible clogging

After confirmed bacterial contamination, shock chlorinate immediately, then retest within seven days. For filters, carbon cartridges typically need replacement every 6–12 months; RO membranes every 6–24 months. Document everything — your records reveal patterns that a single test never will.

What Your Well Water Test Results Mean & When to Act

Getting a water test report back is one thing — knowing what to do with the numbers is another. Let's break down what actually matters.

If total coliforms test positive, retest within seven days and consider shock chlorination immediately. Detect E. coli? Stop drinking the water now, call your health department, and disinfect the system — no waiting.

Nitrates above 10 mg/L as NO3–N threaten infant health through methemoglobinemia. Reverse osmosis or ion exchange resolves it. Arsenic exceeding 10 µg/L signals long-term cancer risk — anion exchange or specialized filtration media are your mitigation paths.

Beyond pathogens and contaminants, track pH, TDS, iron, and manganese annually. Shifts in these numbers reveal corrosion trends, scaling buildup, or aesthetic problems before they become serious — and guide smarter treatment decisions.

How to Find a Certified Lab & Get Your Well Water Tested

Finding the right lab doesn't have to be complicated — start by pulling up your state environmental or health department website, or use the EPA's certified laboratories search tool, and look for labs accredited to test for bacteria, nitrates, metals, and VOCs.

Once you've identified candidates, call ahead to confirm they accept private well samples, then request sterile containers for coliform and E. coli testing. Ask specifically about local concerns — arsenic, nitrates, fluoride, VOCs — and verify the lab reports results alongside EPA MCLs or state action levels.

Bacterial samples typically must arrive within 36 hours, so nail down collection, preservation, and delivery instructions before you do anything else.

Compare fees and turnaround times, then keep every report to track changes and support future retesting decisions.

Frequently Asked Questions

What Are the 5 Main Indicators of Water Quality?

We recommend testing for five key water quality indicators: total coliform bacteria, nitrate levels, total dissolved solids (TDS), pH balance, and specific inorganic metals like arsenic, fluoride, iron, manganese, and lead.

How to Test Well Water for Arsenic?

We'll want to collect a raw water sample in a lab-provided container, send it to a state-certified laboratory, and compare results against EPA's 10 µg/L arsenic MCL to determine if treatment's necessary.

What Are the 5 Parameters of Water Quality?

We recommend testing these five key parameters: physical properties, chemical composition, biological safety, major ions and hardness, and metals/trace contaminants. Each reveals a different layer of what's truly in your water.

What to Check for Water Quality?

We'll want to test for total coliform bacteria, E. coli, nitrate levels, TDS, pH, and site-specific contaminants like arsenic, fluoride, and VOCs—each one revealing a critical layer of your water's safety story.