With recent reports of mandatory water conservation in several counties across Iowa, some people may be switching their water source from Rural Water to a private well. We wanted to share some resources, for both human and livestock consumption, if you are considering making this shift.
Private well water as drinking water
Private well water is different than Rural Water supplies. Rural Water supplies, such as the Poweshiek Water Association and the Iowa Regional Utilities Association, are public water systems that are regulated by the Iowa Department of Natural Resources to test regularly and maintain specific water quality standards. Private well water quality is unregulated, and it is entirely the responsibility of the owner of the well to test and maintain its water quality.
Iowa has a unique program called Grants-to-Counties, that allows for free or very low-cost annual testing of private wells. It is recommended by ISU Extension and Outreach, Iowa Department of Natural Resources, Environmental Protection Agency, and the Centers for Disease Control and Prevention that private well owners test their well water quality annually. To access this program, the well sample must be taken by a county department of environmental health employee. You can find your county contact on this list (https://docs.google.com/spreadsheets/d/e/2PACX-1vSN9_vM3stj69X3-4qojMfxrkIGuP4dkCfZYo1DI9g8FSyJrs4SbfRYuDRPulMxStPClHPxdB1io1GR/pubhtml).
Pollutants like bacteria, arsenic and nitrate are found at elevated levels in 10-30% of private wells in Iowa (Source: Iowa Department of Health and Human Services). The Grants-to-Counties program that allows for free or low-cost annual testing of private wells covers yearly tests for bacteria, nitrate, arsenic and manganese. While all four of these pollutants are covered under the program, it is best to talk to your local private well expert (contact list linked above) to understand what the local water quality issues are. At a minimum, you should test annually for bacteria and nitrate.
Additional Resources:
- ISUEO information on drinking water in Iowa is available here.
- ISUEO information on the Private Well Stewardship program and where it is offered across the state is available here.
Private well water for livestock
Some landowners may use well water for livestock. Livestock are also sensitive to pollutants in drinking water, although species, age and stage of production influence sensitivity. In general, guidelines for human consumption are more stringent than those for livestock consumption. The following are some general guidelines for livestock water pollutants:
- Coliform bacteria: Less than 5,000 organisms per 100 milliliters (Environmental Protection Agency)
- Fecal coliform: Less than 1 per 100 milliliters (Missouri Extension Publication No. EQ381)
- Nitrogen: Both nitrite-nitrogen and nitrate-nitrogen are of concern for livestock:
- Nitrite-nitrogen: Less than 10 milligrams per liter (ISUEO Publication IPIC 204)
- Nitrate-nitrogen: Less than 300 milligrams per liter (ISUEO Publication IPIC 204)
- Total dissolved solids: Less than 5,000 milligrams per liter (NDSU Extension Publication AS1764)
- pH: Above 5.5 and below 8.5 (Missouri Extension Publication No. EQ381)
- Sulfates: Less than 500 milligrams per liter (NDSU Extension Publication AS1764)
High bacteria concentrations in livestock drinking water can cause infertility and low milk production. Water high in total dissolved solids also leads to reduced milk production and gains. Acute nitrate/nitrite poisoning can quickly kill or cause an animal to go down because it limits the ability of blood to carry oxygen and causes oxygen deprivation. Prolonged exposure to even very low levels of nitrite can cause degeneration of the brain, lungs, heart, liver, kidneys, and testes. Moderate levels of sulfate tends to deter consumption, create loose stools, and alters bioavailability of other minerals while high levels can create neurological problems. Nitrogen and sulfur levels in the feed need to be considered in addition to water when evaluating toxicity risk.
Each pollutant affects animals differently, and without water quality analysis, diagnosing an issue when death, illness, or performance drags is difficult. Those using private well water for livestock are encouraged to test the well’s water quality annually. Speak to your county’s private well expert (contact list linked above) to understand the water quality issues in the area, and what additional tests may be needed. If livestock water is suspected of causing health problems, call your herd veterinarian for assistance to diagnose the issue.
Additional Resources: