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xxxEND_PAGE:deq11_b144_0857_0862_1 Here is a recent article (06/12/2014) about the changes in lime addition at the Flint water plant. It might be a bit challenging to make pH adjustments quickly in the finished water if they had to make this significant lime addition adjustment. High pH from lime softening plants has been associated with consumer issues in the past. See below for a background document about lime softening and a WHO document about the health effects of both high and low pH values. Skin rashes are known to be caused by extreme pH variations in drinking water. Hope some of this info is helpful. Joe Carpenter FLINT, MI -- Workers at the city's water treatment plant have bumped up their use of ime in an effort to cut down on both water hardness and rising customer complaints. Daugherty Johnson, utilities administrator at Flint's water treatment plant, said today, Fume 12, that 75 percent of raw water is now being treated with lime compared to 25 percent treatment when the city made the imitial switel: from using Lake Huron to using the Flint River as a drinking water source on April 25. Background info about lime softening: Health Effects of pH -- WHO J faowouho intiwater sar EFFECTS ON HUMANS Exposure to extreme pH values results in irritation to the eyes, skin, and mucous membranes. Eye irritation and exacerbation of skin disorders have been associated with pH values greater than 11. In addition, solutions of pH 10—12.5 have been reported to cause hair fibres to swell (/0). In sensitive individuals, gastrointestinal irritation may also occur. Exposure to low pH values can also result in similar effects. Below pH 4, redness and irritation of the eyes have been reported, the severity of which increases with decreasing pH. Below pH 2.5, damage to the epithelium is irreversible and extensive (/0@). In addition, because pH can affect the degree of corrosion of metals as well as disinfection efficiency, it may have an indirect effect on health.