Mercer County Public Health Profile Report
Fecal Coliform or E. coli in Private Wells: Percent of Wells with Fecal Coliform or E. Coli Detected, September 2002 through December 2018
Mercer2.9 95% Confidence IntervalNADescription of the Confidence IntervalThe confidence interval indicates the range of probable true values for the level of risk in the community.
A value of "NA" (Not Available) will appear if the confidence interval was not published with the NJSHAD indicator data for this measure.
State NA U.S. NANA=Data not available.
Mercer Compared to State
Description of Gauge
Description of the GaugeThis graphic is based on the county data to the left. It compares the county value of this indicator to the state overall value.
The county value is considered statistically significantly different from the state value if the state value is outside the range of the county's 95% confidence interval. If the county's data or 95% confidence interval information is not available, a blank gauge image will be displayed with the message, "missing information."NOTE: The labels used on the gauge graphic are meant to describe the county's status in plain language. The placement of the gauge needle is based solely on the statistical difference between the county and state values. When selecting priority health issues to work on, a county should take into account additional factors such as how much improvement could be made, the U.S. value, the statistical stability of the county number, the severity of the health condition, and whether the difference is clinically significant.
- Excellent = The county's value on this indicator is BETTER than the state value, and the difference IS statistically significant.
- Watch = The county's value is BETTER than state value, but the difference IS NOT statistically significant.
- Improvement Needed = The county's value on this indicator is WORSE than the state value, but the difference IS NOT statistically significant.
- Reason for Concern = The county's value on this indicator is WORSE than the state value, and the difference IS statistically significant.
Why Is This Important?Coliform bacteria are organisms that are present in the environment and in the feces of all warm-blooded animals and humans. Coliform bacteria will not likely cause illness. However, their presence in drinking water indicates that disease-causing organisms (pathogens) could be in the water system. Most pathogens that contaminate water supplies come from the feces of humans or animals. Testing drinking water for all possible pathogens is complex, time-consuming, and expensive. It is relatively easy and inexpensive to test for coliform bacteria.
How Are We Doing?Between September 2002 and December 2018, fecal coliform or E. coli was detected in 2.0 % of 111,010 private wells in sampled New Jersey. Fecal coliform or E. coli was most commonly detected in Somerset (4.3% of wells), Sussex (4.2% of wells), Passaic (3.4% of wells), Hunterdon (3.2% of wells), Warren (3.2% of wells), Mercer (2.9% of wells) and Union (2.8% of wells) Counties. Online maps showing detection of fecal coliform or E. coli are available at the county level, municipal level, and for 2 mile by 2 mile grids from NJDEP, [http://arcg.is/1CPkHyC].
What Is Being Done?The New Jersey Private Well Testing Act (N.J.S.A. 58:12A-26 et seq.) became effective in September 2002. The PWTA requires the buyer or the seller of a property to test untreated well water prior to the sale and review the results prior the closing of title. It also requires landlords to test the private well water supplied to their tenants every five years and provide their tenants with a written copy of the results. The data generated by this program are provided to the homeowners by the laboratory performing the analyses and then sent to the New Jersey Department of Environmental Protection (NJDEP). The NJDEP notifies local health agencies when a well within their jurisdiction is tested under the PWTA. The data from the PWTA are used by NJDEP to assess the quality of the water from private wells throughout the state.
Note**Results by county are suppressed when the number of tested wells was less than 10. Denominator is the number of tested private wells. Data Source: NJ Department of Environmental Protection, Division of Water Supply and Geoscience, and Division of Science, Research, and Environmental Health, obtained on March 2, 2020.
Measure Description for Fecal Coliform or E. coli in Private Wells
Definition: Percent of tested private wells with fecal coliform or E. coli detected
Numerator: Number of tested private wells with fecal coliform or E. coli detected
Denominator: Number of tested private wells in a specified period of time