By late-July standards, the Rivanna River was racing on Saturday, thanks to the 2 to 3 inches of rain that had fallen during the week.

Under a crystalline morning sky, a group of about a dozen kayakers slid into the latte-hued water at the Rivanna River Co.’s new launch site off East High Street.

The muddy water surged over rocky patches and shoals that are normally exposed, the Class II rapids thrilling the mostly novice paddlers.