The San Diego County Water Authority is notifying residents in three cities that their water service could be impacted and to expect nighttime work this week during work on San Diego’s First Aqueduct. Work has been ongoing to extend the life of the historic First Aqueduct, and the San Diego County Water Authority announced the project has reached the halfway point. However, as crews transition to Phase Two of the project, construction will take place around the clock for 10 days from Feb. 23 to March 4.