In the face of a crippled economy, Chesterfield County has sold more than $90 million in general obligation bonds for capital projects and seen its triple-A bond rating from the nation’s top three credit-rating agencies reaffirmed. Only a handful of local governments get the top grade from the agencies, which can mean lower borrowing costs. The county has had the highest ratings from all three—Standard & Poor’s, Moody’s Investors Service and Fitch Ratings—since 1997.