Bob, Alex, and Deanne discussed the following specifics regarding the groundwater storage indicator

1.    Grouping of wells:  the downloaded data do not include any information to group the wells by, but we do have geographic locations.  Therefore I suggest we confine our grouping effort to making a relatively simple division by surface location.  For Napa the 24 wells divide into 7 in the Milliken-Sarco-Tulucay area and 17 in the main basin, with none in Carneros;  for Sonoma we can use the two-part division Chris mentioned if Lisa & Alex agree.

This was agreed upon as our grouping method.

2.    Base period:  I have plotted data on total vineyard acres for the period of GW data.  The plot suggests to me that the base period should be either 1980-1994 (a period of relatively uniform rise in total vyd acres) or 1980-1999 (including 5 additional years when vyd acreage remains relatively flat).  Probably the latter is best, since it includes a full 20 years.  It would be convenient if this worked out for Sonoma as well, but it's not essential that we have the same base period.

Sonoma will get the same vineyard crop acreage data from the Ag. Commissioner's Office and look at it the same way. We will check for Sonoma which is the bigger driver- vineyard development or residential development. Then Alex will use the corresponding data.

3.    Averaging:  Chris's example seems to suggest that the procedure be followed for each well separately.  I don't know why we can't use the datasets Alex & I have prepared, which give an average water level for all sites, and carry out Chris's procedure using average values, instead of doing the analysis separately for each well.  Of course the wells need to be grouped as discussed under item no. 1 above, but my suggestion is to use the average for the group rather than individual wells.  Based on the work I did on the 24 Napa wells, I think the simple unweighted average would be adequate;  I found that weighting the average according to surface area was fairly time-consuming and made very little difference for the Napa data.

Decided to average the whole group of wells.

Next Steps- Bob will finish his analysis with these parameters and Alex will follow suit.