Model Water Efficient Landscape Ordinance (MWELO) - Frequently Asked Questions (FAQ)

Additional information on the Model Water Efficient Landscape Ordinance is available on this site, or you may contact the LATC with your question(s).

  • What is the history behind the Model Water Efficient Landscape Ordinance?

    Assembly Bill (AB) 325 of 1990 created the Water Conservation in Landscaping Act requiring the Department of Water Resources (DWR) to develop a Model Water Efficient Landscape Ordinance (MWELO). This Model Ordinance was adopted and went into effect January 1, 1993, requiring all local agencies to adopt a water efficient landscape ordinance, unless proven unnecessary, by 1993. In 2004, AB 2717 requested the California Urban Water Conservation Council (CUWCC) to convene a task force in order to evaluate and recommend improving the efficiency of water use in urban irrigated landscapes. The outcome was 43 recommendations, some of which included updates to the Ordinance. In 2006, AB 1881 was enacted requiring DWR to update the Model Water Efficient Landscape Ordinance reflecting the recommendations of the CUWCC task force and public comment. The updated MWELO went into effect January 1, 2010, was updated again by Executive Order, and has been in effect since December 1, 2015.

  • What is the purpose of the Model Water Efficient Landscape Ordinance?

    The principal intent of the new Model Water Efficient Landscape Ordinance is to update existing regulation reflecting improvements since the early 1990s, in landscape design, irrigation technology, and water management. Additional changes were made to regulation that would further specify water conservation efforts; for example, delineating specific irrigation time periods and prohibiting guidelines for common interest developments banning the use of low water-using plants. For more information, please visit the Department of Water Resources’ Water Efficient Landscape Ordinance website.

  • Did anything change in the updated Model Water Efficient Landscape Ordinance affecting licensed landscape architects?

    Specific to the landscape architecture profession, the updated Model Water Efficient Landscape Ordinance will now explicitly require a licensed landscape architect, licensed landscape contractor, or any other authorized person (or irrigation designer for irrigation design plans) to sign off on the landscape design plan, irrigation design plan, and grading design plan. All other requirements in the original Model Water Efficient Landscape Ordinance pertinent to the completion of the landscape documentation package are essentially unchanged (including the requirement for an irrigation audit by certified landscape irrigation auditor).

  • Will a licensed landscape architect be required to receive any certifications in order to comply with the Model Water Efficient Landscape Ordinance?

    No. Licensed landscape architects will still perform their duties as prescribed in the Landscape Architects Practice Act (Act).

  • My local agency has its own water efficient landscape ordinance (WELO), which ordinance should I use?

    Always use the local water efficient landscape ordinance; a city or county may adopt a local ordinance that is at least as effective as the state Model in conserving water. Local ordinances reflect local water supply, local climate conditions and other factors. A 2015 Executive Order updated the Model Water Efficient Landscape Ordinance which became effective December 1, 2015.

  • Can a licensed landscape architect perform irrigation audits?

    No. In order to comply with the Model Water Efficient Landscape Ordinance irrigation audits shall be conducted by a certified landscape irrigation auditor. Licensed landscape architects may become certified. A certified landscape auditor is a person certified to perform landscape irrigation audits by an accredited academic institution, a professional trade organization or other program such as the US Environmental Protection Agency’s WaterSense irrigation auditor certification program and the Irrigation Association’s Certified Landscape Irrigation Auditor program.