January 2016 🍂
Landscape Irrigation Ordinance Restrictions Are in Effect - Are you Ready?
Author: Chad Kennedy, Landscape Architect, ASLA

Upon recent trips to California, several vacationing visitors were quick to notice and comment on obvious changes to California's neighborhood landscapes. Changes of which have evolved mostly within the last two or three years. Their comments revolved around a lack of vibrant plants and how brown the lawns and neighborhoods had become. In the wake of a disastrous string of California drought plagued years, Governor Brown, in public fashion, issued Executive Order B-29-15 on January 17th, 2014. The result has been a heightened awareness of water use, acceptance of "brown" as the new "green", and statewide reductions in water use. This, however, hasn't come without a great deal of confusion and uncertainty. Homeowners, municipal governments, land developers, and landscape architects alike have all been unsure of water allowances, how to submit for permits, and how to interpret these new regulations. This article will hopefully clear the air on what changes have occurred and give some direction on how to move forward in a compliant and constructive fashion.

Genesis of Ordinance Updates
An important facet of the Governor's executive order was a requirement for the Department of Water Resources to revise and update the State Water Model Efficient Landscape Ordinance (commonly referred to as MWELO), which governs all water use in ornamental landscapes. The revised ordinance was laboriously debated over and rewritten several times before a final ordinance was finally put into effect on December 1, 2015. This means a statewide ordinance is now in place that trumps any local jurisdiction ordinances not revised and readopted by December 1st. This statewide ordinance however is just a minimum requirement. Some jurisdictions have elected to adopt and enforce stricter ordinances. (Click here to download the most current version of the ordinance.)

Applicable Landscapes
Significant changes occurred to the designation of projects that must abide by MWELO regulations. Below are the major changes that occurred between the 2010 version and 2015 versions of the ordinance:

  • New construction projects equal to or greater than an aggregate 500 s.f. of landscape area are subject to the ordinance. (In the 2010 version this was 2,500 s.f. commercial / 5,000 residential.)

  • Rehabilitation projects equal to or greater than an aggregate 2,500 s.f. of landscape area are subject to the ordinance. (In the 2010 version this was not an aggregate s.f.)

  • A prescriptive approach can be used for landscapes smaller than 2,500 s.f. (In the 2010 version there was no prescriptive method.)

Landscape Design
A variety of adjustments were made to the requirements for landscape design including plant type restrictions and soil preparation. The following significant changes were made:

  • High water use plants, characterized by a plant factor of 0.7 to 1.0, are prohibited in street medians. (This did not exist in the 2010 version.)

  • 3" of decorative mulch are required for all exposed soil surfaces. (In the 2010 version this was 2".)

  • For landscape installations, compost, at a minimum rate of four cubic yards per 1,000 s.f. of permeable area, shall be incorporated to a depth of six inches into the soil. (This did not exist in the 2010 version.)

  • Model homes must have signs that include information about site water use as designed per the local ordinance. Signs must specify who designed and installed the water efficient landscape. Information must also be included to demonstrate low water use approaches to landscaping such as using native plants, graywater systems, and rainwater catchment systems . (This did not exist in the 2010 version.)

Landscape Irrigation
Significant changes occurred in the way water allowances and usage are calculated including, adjustments to the Maximum Applied Water Allowance and the Estimated Total Water Use equations. Additions of irrigation system components for water efficiency and loss prevention were added. Major revisions are listed below:

  • A water meter is required on all non-residential landscapes over 1,000 s.f. and residential landscapes over 5,000 s.f. (This did not exist in the 2010 version.)

  • Flow sensors are required on all non-residential landscapes and residential landscapes over 5,000 s.f. (This was just a recommendation in the 2010 version.)

  • Master shut-off valves are required on all projects except landscapes that make use of technologies that allow for the individual control of sprinklers. (This did not exist in the 2010 version.)

  • All sprinkler heads must meet a 65% or higher efficiency. (This did not exist in the 2010 version.)

  • Check valves are required on all sprinkler heads at low points. (This did not exist in the 2010 version.)

  • Landscape areas less than 10' in width cannot be irrigated with spray heads. (In the 2010 version this was 8'.)

  • Irrigation audits must be completed for all projects. In multiple landscape installation projects (production homes, etc.) 1 in 7 lots or 15% of the landscape must be audited. (This was clarified in the 2015 document.)

  • Irrigation calculations require that designs meet an average irrigation efficiency of 75% for spray devices and 81% for drip systems. (In the 2010 version this was a project wide average of 71%.)

  • A certificate of completion must now include an irrigation audit performed by an independant party. (In the 2010 version, an independant auditor was not specified.)

Though California has been the recipient of much needed rain in the past few months, reservoir levels remain well below normal and are currently reported at 58% of average storage. Whether or not this brutal stretch of the California drought has come to an end is still up in the air, and perhaps open to debate. What is not open to debate however, is that permanent water related restrictions are now in effect because of it. A fundamental shift has ocurred, forever changing how Californian's approach, construct, manage, and visualize their landscape. To learn more about water related issues and other landscape architecture topics, please visit the publications section of our website by clicking here.

1. California Department of Water Resources. Water Efficient Landscape Ordinance. http://www.water.ca.gov/wateruseefficiency/landscapeordinance/. Accessed January 2016
2. California Department of Water Resources. Daily Reservoir Storage Summary. http://cdec.water.ca.gov/cgi-progs/reservoirs/RES. Accessed January 27 2016
Funding Opportunities

Due date: February 18, 2016

Tire-Derived Aggregate Grant Program (FY 2015-16) - The Department of Resources Recycling and Recovery (CalRecycle) administers a program to provide opportunities to divert tires from landfill disposal, prevent illegal tire dumping, and promote markets for recycled-content products. The Tire-Derived Aggregate (TDA)Grant Program provides assistant to civil engineers in solving a variety of engineering challenges. TDA, which is produced from shredded tires, is lightweight, free-draining, and a less expensive alternative to conventional lightweight aggregates.. For additional information on this and other funding opportunities, please visit our Resource Center.

Media Updates

MWELO Breakfast Seminar 02/18/16

Join us for a free breakfast seminar to learn about recent changes to California water ordinances and how they impact development. Speakers will introduce the updated Model Water Efficient Landscape Ordinance (MWELO or AB1881), review residential conformance requirements, discuss plant and lawn options, and highlight irrigation system options and reporting requirements.

Space is limited so don't wait! Click here to download a copy of the event flyer.

Project Updates

Kaiser Permanente, Manteca Hospital Campus Renovation

O'Dell Engineering staff recently completed the first phase of a multi-phase landscape renovation project at the Kaiser Permanente Manteca Hospital Facility. The project goals were to reduce water usage, improve the aesthetics of the campus and to reduce required maintenance.

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