City of Ames, IA
Home MenuDrinking Water Quality Data
At the end of each month, the Water Treatment Plant staff run reports on the Water Quality Data averages for the previous month. The data is then posted here.
Current Water Quality Data for the Month of October 2024
Raw Water Quality
Non-Carbonate Hardness, ppm: 93
Total Hardness, ppm: 400
Total Hardness, grains per gallon: 23.37
pH: 7.32
Treated Water Quality
Non-Carbonate Hardness, ppm: 96
Total Hardness, ppm: 145
Total Hardness, grains per gallon: 8.47
pH: 9.50
Chlorine residual, ppm: 2.82
Iron content, ppm: 0.01
Fluoride content, ppm: 0.26
Bacterial Samples
Samples Taken: 61
Confirmed Positive Samples: 0
Water Plant and Laboratory Services staff analyze many water supply parameters at various times. Some parameters are tested daily, some annually, and some only once every nine years.
Click here to examine all the drinking water supply characteristics.
The following is further explanatory information regarding water supply analysis and reporting:
National Secondary Drinking Water Regulations (NSDWRs or secondary standards) are non-enforceable guidelines regulating contaminants that may cause cosmetic effects (such as skin or tooth discoloration) or aesthetic effects (such as taste, odor, or color) in drinking water. EPA recommends secondary standards to water systems but does not require systems to comply. Click here for the National Secondary Drinking Water Regulations.
Microbiological standards allow no more than 5.0% of all samples to test total coliform-positive in a month. For water systems that collect fewer than 40 routine samples per month, no more than one sample can be total coliform-positive per month. Every sample that tests positive for total coliform must be analyzed for either fecal coliforms or E. coli. If two consecutive total coliform-positive samples are detected and at least one is also positive for E. coli or fecal coliforms, the system has an acute MCL violation. Click here for the Microbiological Standards.
Lead and copper are regulated by a Treatment Technique that requires systems to control the corrosiveness of their water. If more than 10% of tap water samples exceed the action level, water systems must take additional steps. For copper, the action level is 1.3 mg/L, and for lead is 0.015 mg/L. Click here for the EPA's Lead and Copper Rule.
The City of Ames has proactively undertaken a sampling initiative looking at our finished drinking water and our inventory of 22 wells to determine the prevalence of a class of chemicals known as per-and polyfluoroalkyl substances, commonly referred to by the acronym “PFAS.” This is a huge class of manmade compounds that includes more than 12,000 individual chemicals. Click here for more information on PFAS testing in Ames.
Ames Water Safe from Chromium-6 Concerns
In light of a report issued by the Environmental Working Group, the Ames Water Plant wants to reassure our consumers that drinking water in Ames is free from Chromium-6 concerns. Click here to see the report issued by the Environmental Working Group
In 2014, the City of Ames performed testing for Chromium-6 as part of a larger package of analyses required by the US EPA under the third round of the Unregulated Contaminant Monitoring Rule (UCMR-3). The results ranged from 0.17 to 0.25 parts per billion. Click here to see the Unregulated Contaminant Monitoring Rule (UCMR-3)
The US EPA has not established a Maximum Contaminant Level (MCL) for Chromium-6. Only one state, California, has set its own health standard specifically for Chromium-6 at 10 parts per billion. The results in Ames water were 40 times lower than the exceedingly protective California standard. Click here to see California's health standard for Chromium-6.
If you’re having difficulty conceptualizing just what “0.25 parts per billion” means, think about it this way: That is the equivalent to finding one specific second of video in a movie that is 126 years long!
Chromium compounds can exist in several different forms. For those with a scientific curiosity, the variation comes from differences in oxidation states, or valences. The most commonly found forms in the environment are Chromium-6, Chromium-3, and unoxidized Chromium. Chromium-3 is actually considered an essential micro-nutrient.
Chromium-6 is also known by several different names, including: hexavalent chromium, chromium VI, chrome 6, Cr(VI), Cr+6, or hex chrome. Hexavalent chromium is also popularly known as the “Erin Brockovich chemical.”
The results for all contaminants detected in Ames drinking water are published annually in Ames Water’s Water Quality Report.
Click here for the City of Ames Water Quality Report.
Ames Water and Pollution Control Department's Statement on Nitrate
There have been many news media reports recently regarding nitrate in drinking water. This has prompted questions about the presence of nitrate in Ames water.
The Ames Water Plant uses 22 groundwater wells as its water source. These wells are regularly tested for nitrate, and the results are reported to the Iowa Department of Natural Resources. Water is tested each winter as it enters the Water Plant for treatment. Each spring, all 22 wells are tested individually. The maximum contaminant level for nitrate is 10 milligrams per liter. In all cases, Ames water has tested less than the detection limit for nitrate, which is only 1 milligram per liter.
The City is fortunate to have a safe supply of drinking water, free from the presence of nitrate that some water utilities are currently dealing with. For more information on City of Ames water, please refer to our annual consumer confidence report. A link for this report can be found here.