Webb, who a month earlier had won the Kraft Nabisco Championship, picked up the second of her five wins in the 2006 season. Rounds of 66-68-66 the first three days gave Webb a comfortable lead heading to the final day.
The Australian's four-day total of 270 blew away the previous tournament record of 275 that Grace Park set in '03 and Se Ri Pak tied a year later.
Webb's three-round total of 200 was also a new record. Park had also set the old 54-hole mark of 204 in 2003, while Cristie Kerr matched that on her way to victory in 2005.
Pak's win was her 22nd on the LPGA Tour and qualified her for the LPGA Tour Hall of Fame, where she will be enshrined later this year after having completed her 10th full season on tour.
After 22 years of hosting the PGA TOUR, this is the fifth year the LPGA will compete on the River Course at Kingsmill.
The LPGA heads to New York next week for the Corning Classic, where Hee-Won Han downed Meena Lee in a playoff to win last year.