Lehigh County District Attorney James Martin announced charges Tuesday against the couple, 66-year-old Nancy Tonkin and 69-year-old William Tonkin IV of Emmaus.
Martin says the couple stole hundreds of thousands from the utilities account of the South Whitehall Township finance department between 1999 and last June.
Nancy Tonkin was a township employee for 30 years and handled billing for residential and commercial water and sewer accounts.
Investigators say the couple lost more than $100,000 at casinos in Pennsylvania and New Jersey.
A message left at the Tonkins' home was not immediately returned.