WELO: What Every Architect Should Know (Part 1)
High-efficiency drip irrigation lines installed at grade. Photo courtesy of Hunter Industries Incorporated.
If you're an Architect designing or remodeling a home in California, you've probably run across the terms “WELO” or "MWELO" in your city’s site planning requirements.
“WELO” stands for Water Efficient Landscape Ordinance; and although water-efficient landscaping isn’t a new concept, unfortunately many Architects don't learn about MWELO or its complex requirements until late in the submittal process, leading to last-minute expenses and frustrating delays.
Our state’s chronic drought means the need for water efficient landscaping isn't going away any time soon, so here's the first in a three-part primer on what you need to know about WELO before you submit for permits.
What is WELO?
“WELO” is actually a catch-all term for hundreds of city and county ordinances throughout California that respond to the state's Model Water Efficient Landscape Ordinance (MWELO).
The California Department of Water Resources enacted the MWELO in 2015 to make newly built landscapes more sustainable through efficient irrigation design, appropriate plant selection, soil conservation, stormwater management and, perhaps most notably, water budgets.
The MWELO defined minimum standards for water-conscious landscape design, construction, and management; and it's now referenced by the CALGreen Building Code (Title 24, Part 11, Chapters 4 and 5).
Critically, beyond these minimums, each local agency may adopt its own water efficiency ordinance that is “at least as effective” as the state MWELO. As a result, WELO requirements vary from location to location, and the submittal can range from some simple paperwork to a fully detailed plan set.
These differences can be subtle: the Town of Woodside, for instance, adopted the state MWELO verbatim, only adding a requirement that new pools and spas be covered. The City of Palo Alto requires WELO plans to be signed by only a licensed Landscape Architect or licensed Landscape Contractor. And the Town of Atherton allows the WELO submittal to be deferred until after building permits have been issued. Adding to the confusion, some municipalities call their ordinance “MWELO,” others use “WELO,” and still others dispense with the acronym entirely.
When is a WELO submittal required?
With few exceptions*, every residential, commercial, industrial, or institutional project in California that requires a permit, plan check, or design review will trigger a WELO submittal—usually subject to the following MWELO-defined square footage thresholds:
New construction with landscape areas totaling 500+ sf
Renovation/rehabilitation of landscape areas totaling 2500+ sf
For any project with modified landscape areas totaling 2500 sf or less that requires a permit, plan check, or design review, the state MWELO provides for a simplified submittal; but your local agency may or may not follow this model.
Also recall that these are the state MWELO thresholds, and every agency may make their own submittal criteria even stricter—the Town of Portola Valley, for instance, requires WELO documentation for rehabilitated landscapes of only 1,000 sf or more.
*Exceptions include historical sites, public botanical gardens, some ecological restoration projects and mined-land reclamation projects, and cemeteries.
Read our next article to learn more about the submittal documentation each of these types of projects requires.