OTHER VOICES: City Provides Us With High Quality, Safe Drinking Water

City provides us with high quality, safe drinking water

By SUSAN H. WHITAKER

OTHER VOICES

The Ann Arbor Water Treatment Plant already meets the SWTR's requirements tor filtration, continuous monitoring of disinfectant residuals, and turbidity.

On Sept. 11, The Ann Arbor News published Adam Banner’s “Other Voices” article titled “Ann Arbor resists compliance with water standards law.” The article contained misrepresentations regarding Ann Arbor’s compliance with the Surface Water Treatment Rule (SWTR). Discussions with Frank Porta, utilities director; Harvey Mieske, superintendent of the Water Treatment Plant; Larry Sanford, assistant superintendent of the Water Treatment Plant; and Janice Skadsen, chemist at the Water Treatment Plant, have prompted this letter.

The purpose of the SWTR is to provide additional protection for the public from water-borne disease. Specifically, the SWTR sets minimum standards for the elimination of protozoan (notably giardia) and viral pathogens from the water supply. Compliance is required by June 30,1993.

The Ann Arbor Water Treatment Plant already meets the SWTR’s requirements for filtration, continuous monitoring of disinfectant residuals, and turbidity. The Water Treatment Plant can meet the more stringent disinfectant requirement of the SWTR, except under certain conditions of cold water temperature and high demand. Usually high demand occurs when water temperatures are warm. According to Sanford, “this disinfection requirement is to guarantee that the water is free from viruses and giardia, even though there is no evidence of their presence. We have sampled and found no detectable giardia in our finished water.”

Contrary to what Banner indicated, the SWTR does not change the current trihalomethane (THM) maximum contaminant level of 100 parts per billion (ppb). The Ann Arbor Water Supply System has remained in full compliance with the THM standard of the Michigan Safe Drinking Water Act since 1981. However, it is expected that sometime next year there will be a move to lower the THM limit in the future from its current 100 ppb to a limit somewhere between 25 and 50 ppb.

In order to ensure consistent compliance with the SWTR’s disinfection requirement and the anticipated more stringent standards for THM, the city plans to add an ozonation system to the Water Treatment Plant. (It was one year ago that the consultant completed the ozone treatment study, not two years as Banner stated.) An ozonation system is estimated to cost $7.5 million to design and build, plus increase the Utilities Department’s operations and maintenance costs by $360,000 per year.

The city is committed to compliance with the SWTR. It’s simply a matter of working out the details in a consent agreement with the Michigan Department of Public Health (MDPH). This consent agreement will include a compliance schedule to design the ozonation system by 1994, to construct it in 1995, and to place it in full operation by 1996. This schedule allows sufficient time for a quality design, construction and start-up operation of the ozonation system. It also allows for gradual increases in water rates over a three-year period to finance the construction and operation of the ozone system. The consent agreement will satisfy the MDPH’s requirement to enforce the SWTR. During the three-year period of the consent agreement we will be performing additional monitoring for giardia to confirm that the drinking water is safe.

The city has requested that the MDPH waive the standard statutory public notice requirements of non-compliance with the SWTR during the three-year period covered by the consent agreement. Because Ann Arbor will be in the process of adding the ozonation system and our water will be tested for safety, we believe the language specific for the standard public notice is inappropriate. The city is working with the MDPH on an alternative public notice regarding the consent agreement and the schedule to achieve full compliance with the SWTR.

The Ann Arbor Utilities Department is working hard to provide the citizens of Ann Arbor with high quality, safe and pleasing drinking water. The water in the city of Ann Arbor has been safe in the past, is safe today and will be safer in the future.

Susan H. Whitaker is public information officer for the city of Ann Arbor. Readers are invited to contribute to Other Voices. Please call 994-6863 for information.