Data from the United States Geological Survey show how Lake Nacimiento's water levels have sharply risen over the past 30 days because of the massive amount of rainfall over the region. The lake went from 27% capacity holding 103,630 acre feet of water at the end of December to 69% capacity holding 262,055 acre feet of water on Jan. 10. The grey shaded area represents a lack of data due an equipment malfunction.