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Water Wells

Water Well 500


Effective October 4, 2022, the Sonoma County Board of Supervisors approved a moratorium for new water supply wells. (More Information: Well Moratorium)

Effective March 28, 2022, the Governor of California issued an Executive Order to address the ongoing drought conditions. New water supply wells may be subject to additional permitting requirements. (More Information: Drought Executive Order)

Dry Weather Well Testing

Properties with water wells may need the dry weather well testing. It is required in the following situations:

Resources for Maintaining Wells

WLS-011 Disinfecting Wells

Requirements and Expectations: Permits for Well Construction & Well Pump Test

Permit Sonoma is providing this message in an effort to remind well customers of certain requirements and expectations regarding well construction permits and well pump test permits.

  1. Well construction applications and permits. Well construction applications (Applications) and well construction permits (Permits) must comply with the provisions of the Sonoma County Code, Chapter 25B. Applications must clearly identify the proposed scope of work in the application form and on the site plan. An Application may show one primary well location and up to four alternative locations and multiple wells to be destroyed. All well locations shown on the Application site map are reviewed for compliance prior to issuance of the Permit. A Permit may authorize only one well to be completed and multiple wells to be destroyed. Well locations provided as alternatives after Permit issuance require a revision to the Permit if the issued Permit did not exceed the amount of well locations allowed by county code (revisions take more time and will incur additional review fees compared to identifying potential well locations on the original Application), otherwise a new Permit is required. Final well location and work completed must be identified by submitting a revised site plan prior to final approval of the Permit. All dry holes must be properly destroyed and shown on the revised site plan. The applicant for a Permit must be a well drilling contractor with a valid California C-57 license. Permits are not transferable and is stated as such in the text above the location for the well driller signature on the well application form. The C-57 contractor who applied for and received the Permit is responsible for the work performed under the issued Permit including any work that is sub-contracted.
  2. Well abandonment and destruction work. Wells that are defective or no longer being used must be properly destroyed in order to assure the groundwater aquifers are protected and preserved for current and future uses. Well abandonment and destruction work must comply with the provisions of Section 25B-7 of the Sonoma County Code. The message stated above for well construction applications and permits also applies to well abandonments and destructions.
  3. Emergency wells. Emergency well construction applications and permits must comply with the provisions of Section 25B-5(d) of the Sonoma County Code. The application must state “Emergency Well Permit” or “Out of Water”. The well drilling contractor or the property owner must notify Permit Sonoma by providing a letter stating the necessity of the water well on or before three business days after the onset of the emergency situation. The well contractor shall apply for a well permit within five days after the commencement of such emergency work.
  4. Well pump tests. Well pump tests must comply with the provisions of Section 7-12 of the Sonoma County Code and with Permit Sonoma’s Well Pump Test policy and procedure. Well pump tests must be conducted by or under the direction of a well drilling contractor (C57), a pumping contractor (C61/D21), a Registered Civil Engineer or a Registered Geologist with a valid California license. Persons performing pump tests under the direction of the licensed professionals listed must be working directly for or under the licensed professional such as an employee under responsible charge of the licensed professional. Property owners, that are not any of the licensed professionals listed or are not working directly for or under a licensed professional, cannot perform well pump tests. Permit Sonoma must also be notified at least 24 hours in advance of any pump test. Water yield tests performed on springs are allowed only if the spring has been developed to capture and convey water such as with a spring box or as a horizontal well. Any pump test that does not comply with the pump test requirements will not be approved. For more information regarding dry weather testing, please visit our dry weather testing website.
  5. Requests for inspections. All requests for inspections must be made by either calling our automated phone service, Selectron (707-565-3551), or by using our online inspection resources. In order for Permit Sonoma to provide better customer service and manage the variety of inspection requests received, please be sure to submit inspection requests at least 24 prior to commencing work. Inspection requests may also be made up to five days in advance. While well seal inspection requests may be made up to 9:00 AM the day of seal placement and at least an hour before the seal placement, we also recognize that construction work is often scheduled well in advance of actual construction and we encourage our customers to submit inspection requests with sufficient notification so we can better manage anticipated field work.