Permeable resin-bound surfacing may help a San José project meet the Bay Area's C.3 stormwater rules as the wearing course of a pervious paving system over a designed storage base, laid out using the Santa Clara Valley Urban Runoff Pollution Prevention Program's C.3 Stormwater Handbook. The handbook names pervious concrete, porous asphalt and pavers, so the City decides whether a resin-bound surface is accepted. The surface alone does nothing for compliance.

San José also has a stake its northern neighbors do not share to the same degree: the Santa Clara groundwater basin supplies roughly half of the drinking water for about 1.7 million people. Countywide guidance encourages pervious paving that lets water filter through surface soils, while keeping close control over anything that injects runoff deeper underground.

C.3, the SCVURPPP Handbook and where pervious paving is credited

San José is one of the Santa Clara County permittees under the Municipal Regional Stormwater Permit, Order No. R2-2022-0018 (MRP 3). Since July 1, 2023, development and redevelopment that creates or replaces 5,000 square feet or more of impervious surface is a Regulated Project requiring LID treatment, with the same 5,000 square foot trigger for uncovered parking lots, restaurants, gas stations and auto service uses. Detached single-family homes become Regulated Projects at 10,000 square feet.

Below those lines, projects of 2,500 to 5,000 square feet, and single-family homes of 2,500 to 10,000 square feet, must still include at least one site design measure, such as building patios, walkways, driveways or uncovered parking with permeable surfaces. The countywide C.3 Stormwater Handbook, updated in October 2024, is the design reference, with chapters on site design, treatment measures and hydromodification management and an operations template for pervious paving. Its photos include a pervious concrete parking lot and pervious asphalt draining to a tree well, both in San José.

Valley alluvium, groundwater depth and the 72-hour drain rule

Much of San José sits on the floor of the Santa Clara Valley, where alluvial soils range from gravelly creek deposits to slow-draining clays, and groundwater can be shallow toward the Bay around Alviso. The handbook's infiltration guidelines include a map of groundwater depths across the valley, which is a good first screen before any testing.

The handbook draws a clear line between pervious paving that filters water through surface soils, which it encourages where feasible, and infiltration devices that bypass those soils, such as dry wells and infiltration trenches. For devices, Valley Water's guidelines in the handbook set setbacks from drinking water wells of 600 feet for larger residential sites and 1,500 feet for commercial, industrial and road sites, 100 feet from septic systems, and 10 to 30 feet of separation from seasonal high groundwater, depending on use. Soils must drain standing water within 72 hours, and devices are ruled out on contaminated sites. Single homes on lots under 10,000 square feet are exempt from these setbacks, and any variance needs Valley Water approval. The handbook lists permeable pavement with underground storage among infiltration devices, so the engineer should classify a resin-bound section with a deep stone reservoir clearly and add an underdrain where clay or shallow groundwater makes infiltration unreliable.

San José projects where permeable resin-bound makes sense

Plazas, courtyards and outdoor dining areas at North San José office and research campuses, where large paved areas are being reworked.
Podium courtyards and paseos in Downtown and Diridon area residential towers, usually lined over structure.
Willow Glen and Rose Garden home driveways and patios, using the small-project site design option.
Parking areas at neighborhood shopping centers being redeveloped past the 5,000 square foot trigger.

Larger projects that drain to creeks such as Coyote Creek or the Guadalupe River may also face hydromodification controls. Those can change how the reservoir and outlet are sized.

Specifying the system for City of San José review

Use the handbook's sizing worksheets and show the permeable section in the stormwater plan with infiltration data, reservoir depth, any raised underdrain, and the operations and maintenance arrangements the City requires for treatment measures. A lined section does not infiltrate, so the handbook would count it as impervious. Raise any infiltration-device question early, since Valley Water and the City look closely at anything that sends runoff below the surface soils.

Resin Rock supplies resin-bound systems and does not install them: UV-stable binder, natural stone aggregate blends, trims and the Rock Crete permeable sub-base. Engineers can download our technical data sheets, owners can request an approved installer and usually hear back within 24 hours, and local contractors can apply for installer training.

Before you specify permeable resin-bound in San Jose

Confirm whether the project is a C.3 Regulated Project or a small project needing a site design measure.
Check the handbook's groundwater depth map and plan site-specific infiltration testing.
Classify the section as pervious paving or an infiltration device before design.
Check Valley Water's setbacks for infiltration devices, up to 1,500 feet from drinking water wells.
Ask whether hydromodification management applies to the drainage area.
Plan the operations and maintenance agreement for the permeable area.

Common questions about permeable resin-bound in San Jose

Why is groundwater such a big issue for stormwater design in San José?

Because the Santa Clara groundwater basin provides roughly half of the drinking water for about 1.7 million residents. The countywide handbook encourages infiltration through surface soils, such as pervious paving, but sets strict siting rules for devices that bypass those soils. Your engineer should keep the design on the right side of that line.

Does adding a permeable driveway satisfy the small-project rule?

It can. Under MRP 3, projects creating or replacing 2,500 to 5,000 square feet, and single-family homes from 2,500 to 10,000 square feet, must include at least one site design measure, and constructing driveways or patios with permeable surfaces is on the list. The City confirms during permit review that the measure is built as described.

Can resin-bound be laid over my existing concrete driveway?

As a decorative surface, yes. As a stormwater measure, no. Rain would pass through the resin and then run off the concrete, so it is not a permeable surface for C.3 purposes. For site design or treatment credit, the old slab is removed and the surface is installed on a permeable base such as Rock Crete over an engineered stone reservoir.

Official sources for San Jose

Local rules change. We last checked these sources in October 2026. Confirm current requirements with the reviewing agency before you design, and treat this page as a starting point, not engineering or permitting advice.

Permeable Resin-Bound Surfacing in San Jose, CA