Wow, my sewer bill went way up (or way down). How are sewer bills calculated?

At the 3/2/2021 Board Meeting, the Board of Supervisors approved recalculating sewer rates effective July 2021. Sewer rates were previously recalculated every April, based on the average quarterly water usage during the last three months of the previous year and the first three months of the current year (i.e. during the fall and winter when virtually all water use flows into sewer systems). The same water consumption periods (Oct – March) are used beginning with July and continuing for the following three billing cycles. As a result, some residents observe large fluctuations in their sewer bill from year to year due to their water usage during the preceding winter.