What should we know about water quality operations?
Water quality can be defined as meeting EPA standards, by its hardness, smell and many other ways. The important qualities to homeowners are the safety, smell, taste, and clarity. Although the latter three have some indication of water meeting federal water quality standards, they can all be unacceptable to the user and still be considered safe to drink.
The operation of public drinking water systems is regulated by the Environmental Protection Agency (EPA) and in the state of Iowa, enforced by the Department of Natural Resources (IA DNR). An “Operation Permit” is issued every three years to the entity operating the public drinking water system. That permit describes the “Grade Level” operator qualifications. These qualifications ensure the operator understands the requirements of the water system depending on its complexity, i.e. the quantity of water pumped, treatment, testing, and pipe installation/repair standards.
The Operations Permit also dictates the minimum testing requirements for each type of contaminant and how frequent that test must be performed. One of the tests for one of our water systems had nitrate testing to be performed once a year. Upon getting one elevated test result (close to, but under the maximum acceptable limit), the permit was modified to test for nitrate once per month. The permit may return to once per year if the test results consistently fall in the low end of the acceptable range.
If a test result comes back out of the acceptable range, several options may be performed depending on the contaminant tested. In some cases a repeat test may need to be performed to confirm the first result (such as coliform bacteria, which is harmless, but an indicator of a possible problem), then the operator is to look for a cause to the issue and perform a repair if needed. In other cases, if a sample result indicates high levels of a contaminant that is detrimental to human health, the operator is required to inform the public of the contaminant, the health issue associated with the contaminant and what actions are being taken to correct the problem (for instance E.coli, Nitrates, lead, etc.)
In the case of nitrates (or similar as mentioned above), the source of the problem must be addressed immediately. If a specific well is a source, that well can be shut down until the well produces water within acceptable limits. In cases of surface leakage down to the pump suction, the hole needs to be plugged or protection of the wellhead expanded. If the well does not return to acceptable limits, then water treatment methods must be used to bring the water into acceptable limits. For nitrates, a reverse osmosis machine could be used or a device similar to a water softener with special resin in it can remove the offending contaminant (nitrates or arsenic for instance). Several methods can be used to remove many contaminants and in some cases, a single technology will only remove one offending contaminant. Each one adds to the cost of producing safe water, but must be added when necessary.
In the spring of each year, water system operators are required to report on the operations of the previous year. This report is called “Consumer Confidence Report”. The report lists the violations for the previous calendar year. It lists the levels of contaminants and/or treatment chemicals in the water; for instance chlorine, nitrates, arsenic, radium (and other radioactive elements), E.coli bacteria, coliform bacteria, sodium, copper, and lead. There will also be a description of the water source aquifer and the possible attributes associated with a well pulling from that aquifer. These consumer reports are posted on this website each year and mailed out once per year (usually in June or July).
Information on water quality can be found on many websites, in books, various agencies, and laboratories. Below a couple of web pages maintained by the University of Iowa Hygienic Laboratories. Although the pages are written for private well owners, the information is still pertinent to any consumer of water.
For more information follow the links below:
Water contamination issues and treatment options (in-home or commercially applicable). http://www.shl.uiowa.edu/env/privatewell/WellWaterQualityandHomeTreatmentSystems.pdf
Testing basics, why testing is performed, concerns of various contaminants, etc. http://www.shl.uiowa.edu/env/privatewell/faq.xml#30
Public drinking water systems information from the Iowa Department of Natural Resources. https://www.iowadnr.gov/Environmental-Protection/Water-Quality/Drinking-Water-Compliance
The EPA/CDC also hosts a Safe Drinking Water Hotline phone 800-426-4791 or http://www.epa.gov/safewater/lead
