Last updated: 2026
MWELO.com is a commercial service providing guidance and validation tools for California landscape projects subject to the Model Water Efficient Landscape Ordinance (MWELO). We are not a city, state, or government agency, and we have no affiliation with any California regulatory authority.
Our tools were originally developed to support our own landscape practice — built by professionals who have been preparing, submitting, and obtaining approved MWELO compliance documents across California since 2006. What started as internal tools to streamline our own workflow are now offered to the broader community of California landscape professionals, contractors, developers, and homeowners who need to navigate the same process.
MWELO.com is built on over 20 years of direct experience preparing, submitting, and obtaining approved landscape permits across California. The calculations, logic, and document structure this tool produces reflect that experience and have been developed to align with the requirements of the California Model Water Efficient Landscape Ordinance and the WUCOLS plant water-use classification system.
That said, a validation result from this tool is a compliance assessment, not a permit approval. Permit approval is the exclusive decision of the reviewing authority at your local jurisdiction, and is subject to factors outside the scope of this tool.
Local jurisdictions may have adopted local amendments to MWELO, additional submittal requirements, or interpretations of the ordinance that differ from the standard statewide calculations performed by this tool. Conditions specific to your site — grading, existing vegetation, local water district rules, or plan checker discretion — may also affect the outcome of your permit review. It is your responsibility to verify compliance with the specific requirements of the jurisdiction where your project is located before submitting your permit application.
This tool is explicitly not valid for projects located in the City of Santa Monica. Santa Monica operates under its own water ordinance with requirements that differ from standard MWELO. Do not use this tool for Santa Monica projects.
The Certificate of Completion form included with your compliance documents is provided in accordance with MWELO §492.9. This document is not completed or submitted at the design stage — it is a post-installation document. Once the landscape and irrigation have been installed in conformance with the approved Landscape Documentation Package, the property owner or their authorized designee (which may include the signer of the landscape design plan, the signer of the irrigation plan, or a licensed landscape contractor) completes the certificate and submits it to the local agency to verify that the project was built as approved.
Requirements for submission timing and routing vary by jurisdiction — most commonly it is submitted prior to building permit final. Some jurisdictions also require a copy to be submitted to the local water agency. Check with your local plan checker for the specific submission requirements in your city or county.
The user is solely responsible for the accuracy of all project data entered, including addresses, areas, plant selections, hydrozone assignments, and irrigation methods. MWELO.com performs calculations based on the data provided and does not independently verify the accuracy of user inputs.
The documents generated by this tool is based on the information you provide. MWELO.com is not responsible for errors resulting from incorrect or incomplete data entry.
This tool is intended to assist with MWELO compliance calculations and documentation. It does not replace the professional judgment of a licensed landscape architect, contractor, or other qualified professional. For complex projects or projects in jurisdictions with local amendments, we recommend consulting a qualified professional.
MWELO.com shall not be liable for any direct, indirect, incidental, special, or consequential damages arising from the use or inability to use this tool, including but not limited to permit rejections, project delays, or any other outcomes related to landscape compliance.
For questions about this disclaimer, contact us at hello@mwelo.com.