Sorry for my absence from this blog . . . If you are interested in City of Madison water issues, there are two meetings this week . . . Monday the meeting is on Well 3, Tuesday the meeting is on broader health issues.
Here's the water quality update from the Water Utility
In this issue of the Water Quality update:
- Well 3 Public Meeting - November 27th, 6 p.m.
- Joint Meeting of the Madison-Dane County Board of Health and the Board of Water Commissioners - November 28th, 5:30 p.m.
- Manganese Monitoring Study update
Well 3 Public Meeting - November 27th, 6 p.m.
Water quality issues on the Isthmus and the future of Well #3 will be the focus of a public meeting scheduled for Monday, November 27th at 6 p.m. The meeting will take place in the cafeteria of the Holy Cross Lutheran Church at 2670 Milwaukee Street. Representatives from the Water Utility will discuss historic water quality data for the Well 3 service area including recent manganese sampling results, past and present actions to minimize exposure to carbon tetrachloride, the likely process for abandoning well 3 and replacing it with a new well, and the implications of using well 3 as "reserve supply" until a new well goes on-line. We will also solicit community input into the proposed direction of the planning process. Representatives from the Public Health Department of Madison and Dane County and the Mayor's Office will also attend.
Joint Meeting of the Madison-Dane County Board of Health and the Board of Water Commissioners - November 28th, 5:30 p.m.
Water quality issues as they relate to public health will be the focus of a joint meeting of the Boards of Health and Water Commissioners. An agenda for the meeting can be obtained at the following link,
Manganese Monitoring Study update
In the previous update on October 17, 2006, I summarized the manganese results for Well areas 3, 8, 10, and 29. We have now completed sample collection and analysis for the remaining well service areas. A total of 517 samples were collected from 469 city-wide locations. Over 95% (493 samples) had manganese concentrations below 50 ppb, the aesthetic standard, while less than 1% (3 samples) were above the lifetime health advisory level of 300 ppb established by USEPA. Of the 21 samples with a manganese level between 50-300 ppb, 18 of them had manganese below 150 ppb while the remaining three had a manganese concentration between 151-300 ppb. For the locations with manganese above 300 ppb, three additional samples were collected at each site. All resamples at the three locations were below the aesthetic standard of 50 ppb. The cause of the initial high manganese levels at these locations was hydrant flushing at the time of sampling at one site, an unused tap due to a military deployment at another site, and an infrequently used outside tap at the third location. Results from these follow-up samples were consistent with observations in Well areas 3, 8, 10, and 29. That is, we did not observe any location in the city-wide sample group that consistently had levels of manganese that exceeded the lifetime health advisory level of 300 ppb. Finally, a preliminary analysis of the data suggests that the manganese level at residential taps may occasionally be above the aesthetic limit but is rarely above the lifetime advisory level of 300 ppb.
A comprehensive report is currently being produced by a collaboration between the Water Utility and Public Health Department. The report will focus on four primary objectives: 1) determine the manganese levels in drinking water arriving at residential taps, 2) identify the geographic extent of tap water in excess of the manganese aesthetic standard and lifetime health advisory level, 3) evaluate the effectiveness of uni-directional flushing in removing manganese from water mains, and 4) evaluate potential factors (source water, pipe size and material, hydraulic conditions, etc.) that may be contributing to elevated manganese levels. The report is expected to be completed by mid-January and, if that target is met, our findings will be discussed at the Board of Water Commissioners' January meeting. Stay tuned...
Joseph Grande
Water Quality Manager
Madison Water Utility
608-266-4654
