Introduction: Annual Well Inspection/Maintenance (Well Driller/Specialist)

The benefits of an annual well inspection far outweigh the cost.

An annual well inspection will help identify and correct well problems before they affect water quantity or quality. However, if you aren't trained to conduct a sanitary well inspection, or to take biological, chemical, or physical water samples, these tasks should be performed by your well driller or well service company.

The annual inspection of your well should include:

  • Inspection of the wellhead and well components to assure compliance with OEHS drinking water regulations
  • Flow test to determine well-yield, static water level, and drawdown, along with a check of the pump motor, pressure tank and components
  • Test for physical attributes such as turbidity, sand, color, or odors
  • Analyses of water quality chemical attributes such as iron, manganese, hardness, and pH
  • Evaluation of biological attributes such as biofouling (accumulation of living organisms) and raw water coliform

The benefits of an annual well inspection (and fixing a problem before it becomes a water system crisis) far outweigh the cost. With that in mind, let’s continue our discussion of the physical, biological and chemical analyses that will help keep your water system trouble-free.

More information related to Introduction: Annual Well Inspection/Maintenance (Well Driller/Specialist):

Introduction: Types of Samples

Samples collected from the distribution system serve as windows to the water quality. They allow us to verify that the water in the system is safe for our customers to drink. For what you see though these windows to be accurate and representative of the water in the system, you must collect good samples. This section discusses the importance of good sampling procedures, representative sampling, and the two types of samples that are collected: grab and composite.

Bacteriological & Chlorine Samples

Chlorine is added to drinking water to inactivate and kill pathogens (disease-causing organisms) that may be in source water or distribution pipes. Disinfectant residual monitoring and bacteriological sample analyses are two diagnostic tools that alert you to potential distribution system problems. Specifically, an abrupt drop in disinfectant residuals may indicate a failure of a water treatment process and increased microbial risk for consumers. If a sudden disinfectant residual drop occurs, it may be an indication of a cross-connection or biological growth within the mains, and must be investigated. For this reason, West Virginia requires some form of chlorine to be used during disinfection. You must monitor the performance of the disinfection system and report the results to OEHS.

Proper bacteriological sampling and analysis is also a crucial diagnostic tool as it determines the presence of pathogens and human waste in water. BacT samples test for coliform bacteria which is present in human feces (fecal coliform bacteria) and in soil contaminated by human waste (non-fecal coliform). A positive BacT result can be the result from operator error, but the possibility that there is a bacteria problem within the distribution system should not be overlooked. If a repeat (triggered or additional/confirmation sample) is unsatisfactory the system must analyze that total coliform-positive sample for fecal coliforms of E.coli. Proper sampling, preservation, and measurement techniques are of paramount importance to obtaining accurate and consistent results that yield a realistic picture of your water quality.


A cross-connection incident could result in cloudy or highly turbid drinking water. Turbidity is caused by suspended solids, such as sand, silt and/or clay. Specifically, turbidity is the amount of light that is reflected off these suspended solids, causing water to look cloudy or dirty. Turbidity is measured in nephelometric turbidity units (NTU’s).

Customers find cloudy or turbid water objectionable primarily because of its appearance, but the main reason turbidity is a concern is its interference with disinfection processes. Bacteria, which are usually present in turbid water, can be shielded from chlorine and other disinfectants because the turbidity-causing particles use the chlorine first. 

The Introduction: Annual Well Inspection/Maintenance (Well Driller/Specialist) slide is featured in the following lessons:

Well System Components

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