Whether a MWELO landscape permit review applies to your yard depends on two things: the size of the landscape and whether the project already needs a permit, plan check or design review. California's Model Water Efficient Landscape Ordinance (MWELO), in Title 23 of the California Code of Regulations starting at section 490, sets water-use rules for those projects. Lawn rebates are separate, run by water agencies under their own rules.
This guide covers when the state ordinance applies, the two ways to comply, how San Mateo County, Palo Alto and Cupertino apply it, and what Valley Water, the Bay Area Water Supply and Conservation Agency (BAWSCA), the East Bay Municipal Utility District (EBMUD), Cal Water and the San Francisco Public Utilities Commission (SFPUC) offer, all as of November 2026. For plant and design choices, see our mid-century modern landscaping guide; this post covers rules and rebates only.
When MWELO applies to a home project
The state text in force as of November 2026 took effect on January 2, 2025. The amendments renumbered the sections, and the Department of Water Resources (DWR) says they clarify the text, carry out two provisions of Government Code section 65596, and otherwise don't modify or add requirements. Under section 491, it applies to these home projects:
New construction with a landscape area of 500 square feet or more that requires a building or landscape permit, plan check or design review.
Rehabilitated landscapes of 2,500 square feet or more that require a building or landscape permit, plan check or design review. The 2,500 square feet counts the modified landscape area (section 490.2).
"Landscape area" means irrigated planting areas, turfgrass and water features. It leaves out building footprints, sidewalks, driveways, decks, patios, gravel or stone walks, other hardscapes and non-irrigated areas designated for non-development, so hardscape doesn't count toward the thresholds. And the ordinance doesn't apply to registered local, state or federal historical sites; if your house is on a historic register, ask your planning department whether that exemption covers your project.
DWR says every local agency must adopt, implement and enforce the state ordinance or a local one at least as effective, so your city's or county's version is the one that controls. Local pages and ordinances may still follow the 2015 text.
Two ways to comply: performance or prescriptive
The state text offers a performance option (section 493) and a prescriptive option (section 492), and it isn't fully consistent about who may choose. Section 491(b) says any project with 2,500 square feet of landscape or less may use either. Sections 491.2(b) and 492(a) describe the choice only for new construction between 500 and 2,500 square feet, and section 491.2(c) requires the performance option at 2,500 square feet or greater. Ask your city which path applies.
The prescriptive measures for residential landscapes, Appendix D before 2025 and now section 492:
Compost at least four cubic yards per 1,000 square feet, worked six inches deep, unless a soil test says otherwise. Soil with more than 6 percent organic matter in the top six inches is exempt.
Plants: climate-adapted plants that need occasional, little or no summer water (average WUCOLS plant factor 0.3) on 75 percent of the landscape area, not counting areas only for edible plants or using recycled water.
Mulch at least 3 inches deep on exposed soil in planting areas, except turfgrass, creeping or rooting groundcovers, and direct seeding where mulch is contraindicated.
Turfgrass no more than 25 percent of the landscape area, none on slopes steeper than 1 foot of rise per 4 feet, and none in parkways under 10 feet wide unless next to a parking strip used to get in and out of vehicles.
Irrigation: weather- or soil-moisture-based controllers with a rain sensor; pressure regulation; manual shut-off valves near the water supply connection; emitters and spray bodies meeting the listed standards, with sprinkler heads at a distribution uniformity of 0.65 or higher; and subsurface or other no-overspray irrigation in areas less than 10 feet wide.
At final inspection, the plants must be identifiable to the inspector, and the permit applicant gives the owner and the local agency a certificate of completion package.
How three Bay Area jurisdictions apply it, as of November 2026
San Mateo County. The county planning department's WELO page, which still describes the 2015 state revisions, covers new projects of 500 square feet or more and rehabilitated projects of 2,500 square feet or more, offers a prescriptive checklist for projects under 2,500 square feet, limits turf to 25 percent, and requires landscape water meters for residential landscapes of 5,000 square feet or more.
Palo Alto. The city's MWELO submittal guidelines, revised April 18, 2018 and written for the 2015 state text, apply the 500 and 2,500 square foot triggers to residential and commercial projects that require a permit, plan check or design review, and describe the prescriptive path as available only to projects under 2,500 square feet. The guidelines call for:
a landscape design plan signed by a licensed landscape architect or licensed landscape contractor, plus irrigation and grading plans on the water budget (performance) path, the grading plan signed by a licensed civil engineer;
at inspection, a certificate of installation, a weather- or soil-moisture-based controller and irrigation scheduled only between 8:00 p.m. and 10:00 a.m., with the applicant certifying that the owner has received a third-party irrigation audit report.
Cupertino. The city adopted its updated ordinance on May 4, 2016 (Municipal Code chapter 14.15). For a new home in the R1, RHS or A1 zones on a building permit, its landscaping page lists an informational prescriptive form at 500 square feet of landscape or less, a choice of the prescriptive path or a full Landscape Documentation Package from 500 to 2,500 square feet, and the full package above 2,500 (section 14.15.050). With a planning or grading permit, any installation or rehabilitation of 2,500 square feet or less may use either path.
Cupertino also says that if your landscape was never approved under the ordinance because you haven't triggered it, the ordinance doesn't apply to changes you make, while any change to an approved landscape needs city approval. If you don't know whether an earlier owner's project went through landscape review, our guide to checking a mid-century home's permit history explains where to look. San Jose's pages wouldn't load for us, so ask the city there.
Lawn replacement rebates, as of November 2026
Valley Water (Santa Clara County). Our mid-century modern landscaping guide covers the Landscape Conversion rebate's rate, default cap and funding date; the cap can be higher in cost-sharing areas. You need a pre-inspection and a written Notice to Proceed before removing lawn or buying materials, then have 90 days to finish.
BAWSCA Lawn Be Gone! (Peninsula). BAWSCA's Lawn Be Gone page offers up to $4 per square foot, and its terms for July 1, 2026 through June 30, 2027 set $1.00 to $4.00 by agency, with caps set by some agencies. Participating agencies: Brisbane/GVMID, Burlingame, Foster City/EMID, Hillsborough, Menlo Park, Mid-Peninsula Water District, Millbrae, North Coast County Water District, Redwood City and San Bruno. The terms include:
a Notice to Proceed from your water provider and a pre-conversion inspection before removing lawn;
at least 200 square feet of maintained lawn watered with potable water (smaller projects that remove all of a front or publicly visible lawn may be considered);
low-water plants from BAWSCA's list covering 50 percent of the area when grown, and 3 inches of mulch;
no artificial turf or impermeable surfaces; existing sprinklers removed, capped or converted to low-volume drip, and any new system low-volume drip;
completion within four months, the area kept converted for three years after the rebate (ending on a change of ownership), and local permits followed. New construction doesn't qualify, and the rebate can't exceed your actual costs.
A $300 Rain Garden add-on is offered where the agency takes part; Foster City/EMID and Hillsborough don't. For Valley Water's separate rainwater capture rebate, see our guide to flat roof drainage.
EBMUD. The standard rebate is $1.00 per square foot, or $2.00 for a "Super Rebate" project using sheet mulch and mostly California native plants planted September through February. It's capped at $2,000 per 24 months for residential properties of up to four units. The lawn must have been watered with EBMUD potable water and mowed for at least the past three years, and no work can start before approval. Artificial turf, sod (including no-mow grass), invasive plants, concrete or glued paths, and microspray or bubblers aren't allowed, and the project must be done within nine months.
Cal Water. Its lawn-to-garden rebate requires at least three approved low-water plants per 100 square feet, and artificial turf doesn't qualify.
SFPUC. Its outdoor page lists a laundry-to-landscape graywater rebate of up to $100 and irrigation controller and rain barrel rebates, but no residential lawn replacement rebate.
The non-functional turf law and houses
Cal Water's page on Assembly Bill 1572 says the law doesn't apply to single-family residential homes. It lists the ban on watering non-functional turf with potable water starting January 1, 2027 for public properties, 2028 for commercial, industrial and institutional properties, and 2029 for HOA common areas. Valley Water's page summarizes the same ban as starting January 2027 for public, commercial and HOA properties, so condo and townhouse owners should check with their HOA and water agency.
This is general information as of November 2026, not legal advice. Ordinances, rebate amounts and funding change, so confirm the rules with your city's planning or building department and your water agency before you remove lawn or apply for a permit.
Frequently asked questions
Does replacing my lawn trigger MWELO?
Under section 491 of the state text, only if the project needs a building or landscape permit, plan check or design review and the modified landscape area is 2,500 square feet or more. Your city decides which projects need that review and can set its own procedures, so ask its planning department.
Can I start removing grass before my rebate is approved?
Not with the programs we checked. Valley Water and BAWSCA require a Notice to Proceed before you remove lawn, and EBMUD says no work can begin before approval.
Does artificial turf qualify for a rebate?
No. BAWSCA, EBMUD and Cal Water all exclude it.
Related reading
Wildfire Home Hardening for Hillside Mid-Century Homes in California
Eichler Atrium Cover Options: Drainage, Roofing Over or Enclosing
Mid-Century Modern ADU: Adding a Unit Without Fighting the House
Laundry to Landscape Graywater in California: Bay Area Guide
More guides on this topic: Owning & Renovating a Mid-Century Modern Home
Planning a yard project before you sell or after you buy? Call or text the Boyenga Team at Compass at (408) 373-1660 or (650) 383-8606, or contact the Boyenga Team to talk through what the work could mean for your mid-century home.
