Turbidity

The United States Environmental Protection Agency (EPA) and New York State Department of Health (NYSDOH) set drinking water standards and have determined that turbidity is of health concern at certain levels of exposure. The turbidity, or cloudiness of drinking water is a measure of minute particles in the water which demonstrates the following:

• That the source water is of poor quality.
• That there could be an interference with disinfection.
• That the filtering system is not performing in an acceptable manner.
• That there could be interference in microbiological determinations.
• That disease-causing organisms could survive.

The EPA and NYSDOH have set enforceable drinking water standards for turbidity at less than 0.5 Nephelometric turbidity units (NTU) in 95% of the monthly samples. Also the filtered water turbidity shall never exceed 5.0 NTU. Drinking water which meets the standard is associated with little or no risk and should be considered safe.

By DCDOH

Surface Water Treatment Rule Treatment Technique Violation

MHEL

The New York State Department of Health sets drinking water standards and has determined that the presence of microbiological contaminants is a health concern at certain levels of exposure. If water is inadequately treated, microbiological contaminants in that water may cause disease. Disease symptoms may include diarrhea, cramps, nausea, possible jaundice, and any associated headaches and fatigue. These symptoms, however, are not just associated with disease-causing organisms in drinking water, but may be caused by a number of factors other than your drinking water. The New York State Department of Health has set enforceable requirements for treating drinking water to reduce the risk of these adverse health effects. Treatments, such as filtration and disinfection, remove or destroy microbiological contaminants.

The information below is provided to help public water supply operators complete public notices for surface water treatment rule violations.

Possible "Explanation of the Problem" Template

Recent severe weather in upstate areas has resulted in deteriorated raw river water quality, including high turbidity measurements, at the raw water intake to the -insert PWSNAME- drinking water treatment plant. Because of the poor water quality, the -insert PWSNAME's- filters have not been able to consistently reduce turbidity to acceptable State standards. Increased turbidity can indicate an increased risk of contamination from microbiological contaminants, such as bacteria and protozoans, including Giardia lambia and Cryptosporidium. The -insert PWSNAME- water plant operators, with the assistance of State staff, are continuing to evaluate treatment options to correct the problem as expeditiously as possible.

Preventative Measures

In some cases, boiling the water or otherwise treating the water may be recommended.  See Microbiological section for boil and treat language.

From Technical Reference WSP 45 8/6/07

See also Cryptosporidium