Rochester, MN  (KROC AM News) - It appears the cost of water service will be on the rise in Rochester over the next several years. The Rochester Public Utilities Board will be presented next week with the findings of a Water Cost of Service Study that recommends higher rates in each of the next three years. The overall impact of the report’s recommendations would boost RPU’s revenues from water charges by about 6-percent per year beginning January 1st. The impact on consumers will vary depending on their usage and rate class, but a presentation to the RPU Board next Tuesday is expected to include estimates on the added costs for the average residential customer. A 3.5-percent increase in water rates that went into effect at the start of 2015 added an estimated 40-cents to the average residential monthly bill.