The information in the table below is updated when open dates change or when new rainfall totals data are collected. The latest updates to the data are displayed in bold below. Data and closure information were updated on April 17, 2019.
Groundwater Determinations are CLOSED for the 2018-2019 Season
The Memorandum of Understanding with the State of California Regional Water Quality Control Board allows for wet weather percolation and groundwater testing between January 1 and March 1, and after having received 50% of the average rainfall.
Depth to groundwater determinations can be conducted within ten (10) calendar days following a rainfall of 0.8 inches in a 48 hour period. Sonoma County is divided into 7 geographic areas for this purpose. The amount of rainfall will be posted for each area.
Permit Sonoma has exercised its authority to extend the wet weather testing period for the duration noted in the table above. Permit Sonoma reserves the right to open and close wet weather testing periods after March 1 and takes into consideration rainfall data, soil conditions, weather patterns, and environmental factors. The decision to open for a shorter time frame was based on late season rainfall occurring during mostly dry and warm conditions.
Visit our Inspection Scheduling page to make inspection requests for wet weather percolation/groundwater tests.
Wet weather percolation test: 384
Wet weather groundwater test: 386
View inspection codes for the Well & Septic section