Here are some things you should know about your well water:
You cannot see, taste, or smell most well water contaminants
Most common pollutants: coliform bacteria and nitrates
Coliform bacteria—indicates the sanitary condition of your well
A sanitary well should not contain any coliform bacteria
Presence indicates a potential for disease causing organisms to enter the well
If coliform bacteria are present in the water sample, first re-sample to rule out any error
Check for sanitary defects such as a loose well cap, a crack in the casing, inadequate seal around the well casing
Correct any visible defects, disinfect with bleach solution and re-test
Nitrate—chemical commonly found in agricultural and lawn fertilizer or waste materials such as manure or septic effluent decompose
Natural level of nitrate in Wisconsin’s groundwater is less than 1 mg/L
Drinking water standard for nitrate-nitrogen is 10 mg/L
WI Department of Public Health recommends people of all ages avoid long-term consumption of water with nitrate concentrations greater than 10 mg/L but less than 2 mg/ is preferred
Water greater than 10 mg/L should not be consumed by infants less than 6 months of age or pregnant women
Corrective actions include
extending the casing depth of the well, lowering the depth of the existing well, or drilling a new well may help reduce nitrate levels
use bottled water for drinking and cooking
connect to a public water supply if possible
use a water treatment device designed to reduce nitrate levels such as reverse osmosis
Testing kits are available at Marathon County Health Department or UWSP