The schedule of water charges established in accordance with § 420.22 shall be as follows:
(a) $87 per million gallons for consumptive use, subject to paragraph (c) of this section; and
(b) $0.87 per million gallons for non-consumptive use, subject to paragraph (c) of this section.
(c) On July 1 of every year, beginning July 1, 2017, the rates established by this section will increase commensurate with any increase in the annual April 12-month Consumer Price Index (CPI) for Philadelphia, published by the U.S. Bureau of Labor Statistics during that year. In any year in which the April 12-month CPI for Philadelphia declines or shows no change, the water charges rates will remain unchanged. Following any indexed adjustment made under this paragraph (c), revised consumptive and non-consumptive use rates will be published in the Federal Register by July 1 and posted on the Commission's Web site. Interested parties may also obtain the rates by contacting the Commission directly during business hours.