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Paso Robles Groundwater Basin

February, 2014 

Paso Robles

New Development Water Conservation Program

On February 25th 2014, the Board of Supervisors approved a resolution adopting the New Development Water Conservation Program. The program implements the Paso Robles Groundwater Basin Urgency Ordinance (Ordinance No.3246), which requires all new development in the Paso Robles Groundwater Basin Area to offset new water use through verifiable evidence or participation in an Approved County Water Conservation Program. Click here to read the resolution.

Through this program, applicants can purchase offset credits that will be generated through a retrofit program run by the County. All new and expanded residential uses are required to offset new water demand through purchase of offset credits in the amount equivalent to 280 gallons per day, unless specific and adequate evidence is submitted during the building permit process indicating that some other offset amount is more appropriate. Offset credits must be purchased prior to final inspection or issuance of a certificate of occupancy. The cost of offset credits will be set to equal the cost of retrofit credits.

November, 2013

Vesting Rights Exemption Determination

On November 26, 2013 the Board approved a resolution that outlines a procedure to use when staff is presented with a request for a Vesting Rights Exemption from Ordinance 3246. Click here to read the procedure and criteria approved by the Board.

Outreach Efforts - Vesting Rights Determination

On October 1, 2013, staff presented the Board of Supervisors with a resolution that outlined a procedure to use when presented with a request for a vesting rights exemption. At that meeting, the Board directed staff to conduct outreach to stakeholders and gather more input.

On October 22, 2013, an email was sent to over 75 addresses representing both individuals and groups that had expressed an interest in the issue of vested rights through emails, letter or testimony. The email asked the recipients to submit ideas on how they believed vested rights determinations should be made. 30 responses were received and those comments were provided to a smaller stakeholder group made up of representatives from the following organizations:

  • Resource Conservation District
  • Vineyard Team
  • Paso Robles Agricultural Alliance for Groundwater Solutions (PRAAGS)
  • Ag Commissioner’s Office
  • Agricultural Liaison Advisory Board (ALAB)
  • University of California Cooperative Extension
  • Farm Advisor
  • Paso Robles Groundwater Basin Overliers for Water Equity (PRO Water Equity)
  • Paso Robles Wine Country Alliance
  • Blue Ribbon Committee
  • Concerned Owners of Rural and Agricultural Lands (CORAL)

On November 6, 2013, the small stakeholder group met to discuss the comments received and came to a consensus on an approach for determining whether there was a vested right. Click here to read the language.

The Board of Supervisors will consider this language on November 26, 2013 when they consider providing direction for staff to define a vested right to complete site preparation, planting, or sale of product pursuant to Ordinance No. 3246.

October, 2013

On October 8, 2013, the Board of Supervisors continued the Urgency Ordinance adopted on August 27, 2013 for two years.

Contact us at 805-781-5600 for more information, or visit

October, 2012

On September 25, 2012, the Board of Supervisors adopted the Paso Robles Groundwater Basin water conservation ordinance. The Ordinance will require large land uses to offset new water use, prohibit the creation of new parcels in the basin and require changes to the County General Plan to be water neutral. The Ordinance will not affect:

  • the cities of Paso Robles and Atascadero or the towns of Templeton, San Miguel or Shandon
  • the drilling of wells
  • the building of single family home

Please contact James Caruso, Project Manager, at (805) 781-5702 for additional information.

July, 2012

On July 26, 2012, the Planning Commission recommended a draft water conservation ordinance to the Board of Supervisors. The Commission held an extensive discussion of the issues and listened to the public testimony. The Commission's recommendation to the Board includes changes to the original draft ordinance. Those changes are found here and appear as underline and bold.

The Board of Supervisors will hold a public hearing to consider the Planning Commission recommended draft ordinance on September 25, 2012 (all hearings are noticed for 9:00 a.m. Please check the Board of Supervisor's web page for placement of this item on the agenda). You may also contact James Caruso, Project Manager, at (805) 781-5702 for information on groundwater issues in North County. 

February, 2012

Garden Soft Program News

The County is pleased to join the cities and communities in establishing a GardenSoft program for the county. is a web site that features a variety of plant choices and irrigation and maintenance practices that are appropriate for different areas of the county. This website will be invaluable to North County residents as they consider switching to more water-efficient landscaping. Go to for great water wise planting ideas for designed for our area.

Water Conservation Ordinances

As directed by the Board of Supervisors, a special water conservation ordinance is being prepared for the Paso Robles Groundwater Basin rural area. A draft of the ordinance is available now.


May, 2011

Paso Robles Groundwater Basin Resource Capacity Study

The Paso Robles Groundwater Basin Resource Capacity Study contains recommended actions that must be implemented through county ordinances and policies. Two public meetings were held in June 2011 in Creston and Paso Robles. At those public meetings, County staff stated that prior to writing actual ordinances and policies, an interim step would be taken that outlines general ways to implement these RCS recommended actions. Please read through the program outline and send any comments or recommendations to James Caruso by September 30, 2011. We have also provided the Interim Water Guidelines mentioned in Item 8 and the Winery Best Management Practices mentioned in item 6 of the attached Program outline.

Read the Groundwater Basin Newsletter which was delivered to over 6000 addresses in North County. It contains information about the groundwater basin condition, water conservation and next steps.

The Paso Robles groundwater basin (the basin) is presently the primary water source for the North County. Communities from Garden Farms to San Miguel and Templeton to Shandon and Creston rely on the basin’s groundwater. Rural residences, urban development, vineyards and other agricultural uses, and wineries all pump water from the underground basin to use for drinking, landscape and agricultural irrigation and to meet the day-to-day requirements of living in an arid environment.

The basin is large--approximately 505,000 acres (790 square miles). There is a long and narrow finger of the basin called the Atascadero sub-basin . It has a different geology and so is looked at separately from the rest of the larger basin. The sub-basin includes the Salinas River corridor area south of Paso Robles and the communities of Atascadero, Templeton and a portion of the City of Paso Robles’ water supply. Groundwater levels in many parts of the basin have declined over the last 12 years.

Looking at the basin map you can also see boundary lines of sub-areas . These sub- areas are used to break up the basin into smaller-sized areas. The idea of sub-areas is to make it easier to identify problem areas. The Groundwater Management Plan for the basin (see section below) uses these sub-areas for water planning purposes.

The County Board of Supervisors has spent several years studying the basin hydrogeology and the demand and supply of the basin’s groundwater. In February 2011, the Board of Supervisors approved The Paso Robles Groundwater Basin Resource Capacity Study (RCS). It links the state of the basin to land use policy, basin monitoring and water conservation. The RCS concludes that the groundwater basin is approaching or has reached its “ perennial yield.” The perennial yield of a groundwater basin is defined as:

The amount of usable water of a groundwater basin that can be withdrawn and consumed economically each year for an indefinite period of time .

The RCS established a ‘level of severity” for the groundwater basin. There are three severity levels for resources from level I to level III. The Board established a level of severity III for the main basin and a level of severity I for the Atascadero sub basin.

California law does not allow the County to limit how much water a property owner pumps from the ground. The County must use only the authority it has to address this issue. The RCS recommended groundwater monitoring, water conservation and land use measures to address groundwater demand. The Board of Supervisors adopted the following recommended actions from the RCS:

Monitoring and Conservation Actions

  1. Initiate the development of a groundwater monitoring program.
  2. Continue studies of the groundwater basin and stakeholder coordination efforts.
  3. Develop and implement, in collaboration with other water purveyors within the Paso Robles Groundwater Basin and the Atascadero Sub-basin, a water conservation outreach and education program for the rural area.
  4. Continue to conduct biannual groundwater measurements.
  5. Amend Title 8 in accordance with the recommendations in the Resource Management System Annual Summary Report.
  6. Require that the new wells be a part of the District groundwater level measuring program if needed.

Land Use Measures Actions

  1. Require new discretionary development that does not use supplemental water to use the California Urban Water Conservation Council’s (CUWCC) best management practices for water conservation and offset 100 percent of its new water use with non-agricultural water.
  2. In rural areas of the basin, do not approve General Plan amendments that result in a net increase in the non-agricultural use of groundwater;
    • Prohibit new land divisions in the rural areas of the basin.
    • All discretionary development shall offset its water use with non- agricultural water, except that proposed Agricultural Processing uses (as defined in the Land Use Ordinance), including outdoor and other appurtenant water use, shall be subject to project- specific land use and/or water conservation mitigation measures required by the review authority based on environmental review.
  3. New wineries shall use best management practices consistent with the Best Management Practices.
  4. Revise the Growth Management Ordinance and the Resource Management System to substantially limit yearly non-agricultural development in the rural areas of the basin.
  5. Develop a landscape ordinance that will limit the amount of turf and other high-water use features on all parcels within the Paso Robles Groundwater Basin, Including the Atascadero Sub-basin.
  6. Work with stakeholders to develop best management practices for prevalent land uses in the basin similar to the winery BMP.

Visit for more information on the Paso Robles Groundwater Basin.

If you have questions about this information please contact James Caruso of the County Department of Planning and Building.