What a difference a year doesn’t make. For anyone who doubts that we’re still in a drought, San Joaquin County’s groundwater “savings account” was even more depleted this spring than last, despite improved rainfall over the course of the winter. Routine surveys of hundreds of wells across the county revealed water levels had dropped about 2 feet on average — not as severe as the 3-foot drop seen the previous spring, but still a decline.Officials had hoped the results might be a little better.“But we weren’t expecting an instant turnaround,” said Fritz Buchman, deputy director of county Public Works.