The city is seeking approval of a $25 million bond authorization request to fund five projects crucial to improving its water supply and distribution infrastructure. The projects would be completed over the next three years, Rob Langenauer, superintendent of water, wrote in an email last month to Mayor Neil M. O’Leary. The $25 million bonding request follows a $17.7 million bond authorization in 2015 that upgraded some of the city’s water infrastructure. Costs for each of the five projects were not included in Langenauer’s memo to the mayor. Pumps and motors provide drinking water, fire flow, storage capacity and pressures needed to meet “elevation challenges” throughout the city, Langenauer said. They carry electricity costs of at least $44,000 per month, he said. In his memo to O’Leary, Langenauer mentioned the water crisis in Jackson, Miss., which began in August after a river near that state’s capital city flooded due to severe storms. The flooding caused the city’s largest water treatment facility to stop treating drinking water, leaving roughly 150,000 residents without safe drinking water, according to national news reports. The facility had been running on backup pumps due to failures earlier in the summer.