Napa Valley’s annual groundwater checkup yielded the verdict that the water table in the world-famous grapegrowing region is “generally very shallow” and that the basin is “full.” There are problem spots, such as the Petra Drive area northeast of the city of Napa that the county is studying. The Coombsville area still faces groundwater challenges, though the county sees the situation as having stabilized. But overall, the county’s 2016 groundwater report by consultating engineers Luhdorff & Scalmanini to the Napa County Board of Supervisors last week emphasized the positive, especially when it came to the valley floor.