PUBLIC NOTICE: WELL #14 RETURN TO SERVICE

PUBLIC NOTICE

Important information about drinking water at Tomah Waterworks

Well 14 returning to service

Treated water from Tomah well 14 contained nitrate exceeding 10.0 milligrams per liter (10 mg/L), the maximum contaminant level (MCL) allowed. An Entry Point 14 sample collected on May 13, 2025, had a concentration of 14.4 mg/L and a sample collected on May 15, 2025, had a concentration of 7.85 mg/L resulting in an average concentration of 11.125 mg/L. This was a violation of State and Federal Safe Drinking Water Regulations.

The Tomah water utility also draws water from four other wells.  The water from the other wells has not exceeded the nitrate MCL of 10 mg/l, and meets all other drinking water requirements.

Well 14 was shut down on May 16, 2025.  Since that time, the Tomah water utility has conducted source water protection activities on the properties adjacent to well 14. It has also conducted investigative raw water investigative monitoring from well 14, and the measurements have been below the MCL of 10.0 mg/l.  The Tomah water utility now believes that well 14 can be safely returned to service.

On May 4 2026, the Tomah water utility will be returning well 14 to service.  We are required to inform you of this action.  Once well 14 goes back into service, the raw water from this well will be tested by the Tomah water utility five days a week.  If the nitrate levels approach or exceed the MCL, the well will be shut down.  The treated water from well 14 will also be analyzed monthly at a certified laboratory.  If there are any MCL exceedances in the future, the public will be informed, and the well will be turned off.

We are required to provide updated public notices quarterly until four consecutive quarterly samples demonstrate that the corrective actions taken by the Tomah water utility are effective.  Subsequent notices will include the results of the samples analyzed by the certified laboratory.

What precautions should be taken at this time? 

There are no special precautions you need to take at this time. If specific actions are required, the Tomah water utility will communicate that information to the public.

What are potential health effects from high nitrate?

Infants below the age of 6 months who drink water containing nitrate in excess of the MCL (10 mg/L) could become seriously ill and, if untreated, may die. Symptoms include shortness of breath and blue baby syndrome. Females who are or may become pregnant should not consume water with nitrate concentrations that exceed the MCL. There is some evidence of an association between exposure to high nitrate levels in drinking water during the first weeks of pregnancy and certain birth defects.

What is nitrate?

Nitrate (NO3-) is a form of nitrogen. It is a natural part of soil and groundwater and is a chemical found in most fertilizers, animal manure, and liquid waste discharged from septic tanks. Higher levels of nitrate and nitrite are sometimes found in surface water (lakes, rivers, and streams) and groundwater from human and animal waste and fertilizer use.

What is being done to correct the problem?

The Tomah water system has implemented source water protection activities near the well.  Investigative nitrate samples have been collected from well 14.  Additional compliance water samples will be collected on a monthly basis, and investigative measurements will be collected on weekdays to ensure the nitrate remains at levels below the MCL. 

If you have questions regarding the safety of our drinking water, please contact:

Jeff Marten

608-374-7431

819 Superior Ave

Tomah

WI

54660