More than half the cost is for planned expansions of two treatment plants that are at or near capacity: Little River and Big Creek.
All told, the projects will cost $523.5 million.
“We always tied changes to our rates to very specific projects,” Clark said.
The county plans to take out bonds to pay for the construction.
The county’s plan calls for increasing the capacity of Little River, which serves Mountain Park and parts of Milton, Alpharetta and Roswell, from 1 million gallons a day to 2.6 million gallons a day. Big Creek’s capacity would increase from 24 million gallons daily to 38 million gallons a day. It serves parts of Roswell, Alpharetta, Milton and Johns Creek.
The additional capacity is needed to handle the growth north Fulton has seen since coming out of the housing crisis, Clark said.
Fulton had been prohibited from expanding capacity at Little River and Big Creek by the state Environmental Protection Division until it complied with a water conservation plan. The prohibition also limited construction in north Fulton by restricting access to sewer service.
In addition to the capacity increases, the projects include upgrading 19 pump stations, extending water mains at Kimball Bridge Road and in Alpharetta, building water main loops in Milton and relocating lines before roadwork is done across the county.