How to test your well water when you are not on city supply

Private wells give households an independent source of water, but the owner is generally responsible for checking its safety. Water can change as wells age, nearby land uses shift, flooding occurs, or equipment begins to fail. Clear water and an ordinary taste do not guarantee that it is free of bacteria, minerals, or other contaminants.

Residents outside the municipal water system should create a testing routine that fits the property and local risks. A certified drinking-water laboratory can identify which samples are needed, explain collection requirements, and provide results in a format that a health professional or regulator can review.

The City of Susanville Public Works Department provides information about public infrastructure and utility services through its Public Works website. Private well owners can use that resource for general municipal contacts while coordinating well-related health questions with the appropriate county or state agency.

Know when well water needs testing

Test a private well at least once each year for total coliform bacteria and E. coli, especially when the water is used for drinking, cooking, making ice, or brushing teeth. Annual testing establishes a baseline and can reveal changes before anyone becomes ill. A new owner should also test soon after purchasing a property.

Additional testing is appropriate after flooding, wildfire, construction near the well, a broken well cap, repairs to the pump or plumbing, or a noticeable change in taste, odor, color, or pressure. Test promptly if someone in the household develops unexplained gastrointestinal symptoms or if a nearby septic system has failed.

A private well is different from a city utility connection because there is no municipal treatment process routinely monitoring the water before it reaches the tap. The well casing, pressure tank, storage system, treatment equipment, and household plumbing all affect the final sample.

Prepare before collecting a sample

Choose a laboratory certified by the California Environmental Laboratory Accreditation Program or another recognized drinking-water program. The local environmental health office can help identify approved laboratories and may provide guidance for wells affected by a particular incident. Ask the laboratory which bottles, preservatives, forms, and holding times apply to each analysis.

Decide what to test based on the well’s location and history. Basic screening commonly includes total coliform and E. coli bacteria, nitrate, and nitrite. In areas with naturally occurring minerals or geothermal activity, a professional may recommend tests for arsenic, uranium, fluoride, boron, iron, manganese, hardness, or total dissolved solids. Agricultural, industrial, fuel-storage, or mining activity may justify pesticide, volatile organic compound, or metals testing.

Do not use a random household container. Laboratory bottles may contain preservatives or require sterile handling. Keep the sample away from disinfectants, food, soil, and dirty surfaces, and follow the lab’s instructions exactly.

Collect a reliable water sample

Use a cold-water tap that is supplied directly by the well, such as a kitchen faucet. Remove faucet aerators, filters, hoses, and other attachments if the laboratory instructs you to do so. Disinfect or clean the outlet only when directed; some sampling procedures require a specific method, while others prohibit cleaning agents that could affect bacteria results.

Let the water run for the time specified by the laboratory, then fill each bottle without touching the inside of the cap or container. Leave the required air space, if any, and secure the cap firmly. Record the collection date, time, address, well identification, water source, and any treatment equipment that was operating.

Deliver or ship the sample within the laboratory’s required holding period. Bacteria samples often have a short deadline and may need refrigeration in a cooler, but they should not be frozen. If a sample arrives late, warm, overfilled, or contaminated, the lab may reject it and require recollection.

Match the test to the possible hazard

A basic test package is a starting point rather than a universal answer. Results should be interpreted with the well’s construction, geology, household plumbing, and possible contamination sources in mind. The following guide shows common reasons for selecting particular analyses.

Test or indicator	What it can suggest	When it may be useful
Total coliform and E. coli	Possible contamination from soil, surface water, or sewage	Every year and after flooding or repairs
Nitrate and nitrite	Influence from septic systems, fertilizers, or animal waste	Homes with infants, agricultural areas, or shallow wells
Arsenic, uranium, or fluoride	Naturally occurring minerals in groundwater	Where geology or local data indicates a concern
Iron and manganese	Staining, metallic taste, or plumbing deposits	When water is discolored or leaves scale
Volatile organic compounds	Possible fuel, solvent, or industrial contamination	Near tanks, businesses, spills, or contaminated sites
Pesticides or herbicides	Agricultural or landscape chemical movement	Near treated fields, orchards, or intensive landscaping
Hardness and total dissolved solids	Mineral content and treatment needs	To evaluate scaling, taste, or treatment performance

A positive coliform result does not automatically identify the source or prove that every contaminant is present. E. coli detection is more urgent because it indicates possible fecal contamination. Stop using the water for drinking and food preparation until the laboratory, county health officials, or another qualified professional explains the next steps.

Read the report and respond safely

Laboratory reports may list results in milligrams per liter, micrograms per liter, colony-forming units, or a presence/absence format. Compare each result with the applicable California drinking-water standard or public-health advisory, rather than relying on taste or appearance. Ask the lab to clarify detection limits, estimated values, and quality-control notes.

If bacteria are detected, use bottled water or another confirmed safe source for drinking, cooking, and brushing teeth while seeking guidance. A professional may recommend shock chlorination, inspection of the well seal, repair of damaged plumbing, repeat sampling, or disinfection of treatment equipment. Do not assume boiling solves every problem; it can reduce many biological risks but does not remove chemicals and may concentrate some dissolved substances.

For nitrate, arsenic, solvents, or other chemical concerns, use a treatment method specifically certified for that contaminant. Before buying equipment, confirm the contaminant, select a system with an appropriate certification, and plan for filter replacement and follow-up testing. Keep children, infants, pregnant people, and medically vulnerable household members away from water that officials identify as unsafe.

Maintain the well and your records

Keep a file containing laboratory reports, well depth and construction details, pump and treatment records, repair invoices, and dates of unusual events. Record when filters are changed and when the well is disinfected. This history helps identify gradual changes and gives technicians useful information during an inspection.

Inspect the wellhead periodically. The casing should extend above the ground, the cap should be secure and sanitary, and surface drainage should flow away from the well. Keep fuel, chemicals, animal waste, fertilizers, and hazardous materials away from the well area. Maintain septic systems and avoid landscaping practices that direct runoff toward the well.

Utility customers who also receive city services can review billing information in this utility bill guide, while properties using private wells should track testing and maintenance separately. Questions about municipal services, emergency contacts, or city infrastructure can be directed through the department’s official resources.

Build a dependable testing routine

Use these actions to make private well care more consistent:

• Test annually for total coliform and E. coli, and repeat testing after flooding, repairs, or a change in water quality.
• Ask a certified laboratory or local health authority which chemical tests fit the property’s geology and nearby land uses.
• Collect samples with laboratory-provided containers and deliver them within the stated holding time.
• Keep treatment systems maintained, and retest after disinfection, repairs, or installation of new equipment.
• Save every report and compare new results with earlier samples to spot trends.

Private well owners should arrange testing promptly when a result is positive or water quality changes suddenly. Contact the appropriate local health or environmental office for incident-specific instructions, and use the City of Susanville Public Works Department’s natural gas rate guide for separate questions about municipal gas services and charges. Taking a sample through an approved laboratory is the practical first step toward knowing whether household well water is safe and what action, if any, is needed.