Permeable Resin-Bound Surfacing in Irvine / Orange County, CA

WQMPs, the El Toro Road line and the new regional permit

Orange County sits under two regional water boards. Projects north of El Toro Road, which covers most of Irvine and the rest of central and north county, use the North Orange County Model WQMP from May 2011 and the Technical Guidance Document (TGD) from December 2013. South of El Toro Road, the San Diego Regional Board's permit applies, and the county issued an updated Model WQMP and TGD in July 2026 that serve as the BMP Design Manual there.

In the Santa Ana Region, Order No. R8-2026-0034 replaces the countywide permit, Order No. R8-2009-0030 as amended, when it takes effect. Its priority project list includes new development creating 10,000 square feet or more of impervious surface, significant redevelopment adding or replacing 5,000 square feet or more, and parking lots adding 5,000 square feet or more. The permit names permeable pavements as an example of a control for ministerially approved priority projects, and it requires permittees to submit Uniform Technical Guidance Documents by March 10, 2029. Each city enforces these through its own development review, so the City of Irvine is the approving agency for Irvine projects.

Selenium, cleanup plumes and clay: why infiltration gets screened first

The North Orange County TGD prohibits infiltration in mapped natural pollutant source areas, with selenium named specifically, and within groundwater plume protection boundaries, including those tied to the former El Toro Marine Base and Tustin Marine Air Base, unless a site-specific study shows no harm. It also bars infiltration within 250 feet of contaminated sites, such as those in the state's GeoTracker or EnviroStor databases, unless a site-specific study shows no harm.

Those rules matter in Irvine. The TGD's groundwater map places the El Toro plume boundary across central Irvine, northwest of the former base, and the selenium area over the former Tustin base and parts of northwest Irvine north of the I-405. Add the slow-draining clay soils and shallow groundwater found across parts of the Tustin plain, and infiltration is ruled out on many sites. Where it is prohibited, the TGD points to harvest-and-use or vegetated biotreatment BMPs instead. A lined or underdrained permeable section can still handle surface water, but whether it earns any WQMP credit is the City's decision. The county's Land Development Tool web app shows soil groups, infiltration constraints, groundwater data and the 85th percentile rainfall for a given parcel, which is the right starting point for the engineer.

Where permeable resin-bound fits in Irvine and Orange County

• Plazas, paseos and courtyards in Irvine Spectrum and Irvine Business Complex office and mixed-use redevelopment.
• Common areas, pool decks and walkways managed by village HOAs in Woodbridge, Northwood and newer Great Park neighborhoods.
• Restaurant patios and retail courtyards in shopping centers across central county.
• Coastal homes and hospitality sites in south county, under the San Diego Region rules.

Runoff in most of Irvine flows toward San Diego Creek and Upper Newport Bay. That is a large part of why the county screens infiltration and pollutants so closely.

Specifying permeable resin-bound in a project WQMP

Run the parcel through the Land Development Tool, complete the TGD's infiltration feasibility worksheets, and document the permeable area in the project WQMP with its base depth, liner or underdrain, and a maintenance plan. Projects keep using the current Model WQMP and TGD until 90 days after the Water Board approves the new uniform guidance, so ask the City of Irvine which documents apply on your application date.

Resin Rock manufactures and supplies resin-bound systems; we do not install. Your engineer can pull technical data sheets for UV-stable binder, natural stone aggregates, trims and the Rock Crete permeable sub-base, and owners can request an approved installer, usually matched within 24 hours.