The San Diego County Water Authority announced Thursday its board had adopted a $1.58 billion budget, which included a 3.7 percent increase in water rates to it’s 24 member agencies.  The Water Authority said the rate increase, which it claimed is among the smallest in the past decade, will be passed on to customers at an amount determined by the individual agencies. For example the amount of the increase passed on to Helix Water District customers may be different than those passed on to customers of the city of San Diego.