Tropical Storm Andrea caused minimal erosion to Pinellas County's beaches, according to a preliminary report by University of South Florida researchers. Most of the county's beaches and dunes are still in good shape, said Dr. Ping Wang, a USF professor. But those that were already narrow, such as northern and southern parts of Treasure Island and Pass-a-Grille Beach, are now even shorter. "Basically, the impact is not significant at this point," said he said, adding that the storm had passed through the county so quickly, that there was not enough time for it to cause much erosion. Wang said he plans to survey the beaches next week to quantify how much sand had been lost.