Water Testing Lab

Lab Sign at Great Falls Water Plant

The Great Falls Water Treatment Plant produces an average of 4.5 billion gallons of safe drinking water each year.  The Environmental Protection Agency (EPA) establishes strict guidelines for contaminants in public drinking water systems. Some elements, such as disinfectant residual, are required to be monitored continuously while other constituents, such as radionuclides, are tested once every few years.

At the Great Falls Water Treatment Plant, the process is continuously monitored by in-line meters. In addition, samples of both water in process and treated water are collected and analyzed in-house by trained operators and a trained laboratory technician. Outside laboratories are utilized for some testing. Test results are posted on the Montana DEQ webpage (https://deq.mt.gov/Water/PWSUB/pws/montanadrinkingwaterwatch ) and compiled annually into  a Water Quality-Consumer Confidence Report, which is then distributed to the Great Falls water system users.

Great Falls is classified as a medium-sized community public water system (between 50,000 and 100,000 served).  Therefore, state and federal guidelines require 70 routine sites, scattered throughout Great Falls, be visited each month in order to collect water samples to test for pH, turbidity, and total coliforms.  The in-house water testing lab is located at 1301 Lower River Road. In addition to daily sampling and testing at the plant, the lab analyzes new and repaired City water lines as safe to use and investigates customer complaints. The following tests can be performed on samples of well water, water for medical use, etc. at the lab for the following fees:

Alkalinity $19.00
pH $10.00
Specific Conductance $10.00
Total Coliform & E. coli. P/A $22.00
Total Coliform & E.coli. MPN $26.00
Turbidity $10.00
Heterotrophic Plate Count (HPC) $30.00

 For additional information see "Commonly Asked Questions", or  contact the Water Plant lab at 727-1325.


Click any thumbnail image to view a slideshow

Turbidity Meter & SamplesTest Samples (yellow is positive for Coliform)Tryptic Soy Broth (used to test sterillity of sample containers)Water Operator in the LabJar Testing in the LabOperators Working in the Lab