Permeable resin-bound surfacing can earn stormwater value in Silver Spring and Takoma Park, but the rules depend on which side of the city line the property sits: Takoma Park runs its own stormwater utility, permit and credit program, while Silver Spring is unincorporated Montgomery County. In both, the resin-bound course has to sit on a stone reservoir that stores water and lets it soak in or drain away.

Over an existing concrete driveway or asphalt lot it is only a new surface, and neither Takoma Park nor the county will treat it as a stormwater practice. Below are Takoma Park's credit terms in detail, the county route, the ground conditions in the Sligo Creek and Long Branch valleys, and how to move a project through review.

Takoma Park's fee credit, its permit rule, and the county next door

Takoma Park bills its Stormwater Management Utility Fee by impervious area, at $30 per 500 square feet since fiscal 2026, under a tiered structure the City Council adopted in 2021. The credit program caps the reduction at 50% of the fee, calculated on the impervious area a qualifying facility treats. Permeable pavement is an eligible category, and the City's policy describes it as porous concrete, porous asphalt and interlocking concrete pavers built with a stone aggregate reservoir under the surface and a geotextile over a non-compacted subgrade.

Full credit for the pavement area needs enough subsurface storage, and the City says credit may be reduced where the stone reservoir is less than 12 inches deep. Applications must arrive by April 30 to apply to the billing year starting July 1, the City visits the site before approving, and credits last one to three years under a signed maintenance agreement. Resin-bound surfacing isn't one of the named surface types, so ask the City Engineer whether it will be considered before you commit.

Separately, Takoma Park requires a stormwater management permit for any exterior construction on commercial, industrial or institutional property regardless of size, and for single-family additions disturbing 5,000 square feet or more, designed to City Code Section 16.04.140 and the MDE Stormwater Design Manual. Downtown Silver Spring, Long Branch, Four Corners and Woodside are unincorporated, so properties there use Montgomery County's Water Quality Protection Charge credit and RainScapes rebates (the permeable pavement rebate, as written, covers only certified permeable concrete pavers), and the county's Department of Permitting Services handles development review.

Sligo Creek, Long Branch and old trees: the ground under the reservoir

Both communities drain to Sligo Creek, Long Branch and the Northwest Branch, then the Anacostia, and much of the housing stock predates any stormwater control. Soils are Piedmont silts and clays over weathered rock. Some lots infiltrate well and many don't, so field testing at the footprint is the starting point. MDE's ESD criteria favor Hydrologic Soil Groups A through C and a reservoir bottom at least four feet above the seasonal high water table, which can be hard to meet on stream-valley lots.

One technical conflict needs settling early. Takoma Park's credit policy calls for a geotextile over the subgrade, while MDE's Chapter 5 permeable pavement criteria say filter cloth should not be used between the subbase and soil subgrade and allow a washed sand or pea gravel bridging layer instead. The project engineer should confirm with the City Engineer which detail governs for a permitted project versus a credit-only retrofit.

Mature street and yard trees define both places, and their roots occupy the same ground a reservoir would. Root protection and any tree permits belong in the design conversation from the first site visit.

Where it fits between Old Takoma and downtown Silver Spring

Bungalow driveways and parking pads in Takoma Park, where an accepted design can trim the City's stormwater fee.
Storefront forecourts and patios around Old Takoma and Takoma Junction, where exterior work on commercial property already triggers a City stormwater permit.
Courtyards and plazas in downtown Silver Spring redevelopment, reviewed under the county's ESD process.
Garden apartment walkways and lots along Flower Avenue and in Long Branch, where large paved areas drive fees.
Churches and schools on both sides of the line; in Takoma Park, institutional status means any exterior construction needs a stormwater permit.

Who signs off, and what Resin Rock provides

Inside Takoma Park, the Public Works Department and the City Engineer review stormwater permits and credit applications, with a site visit before a credit is approved and a decision emailed within 30 days of a complete application. In Silver Spring, the county's Department of Permitting Services reviews the stormwater concept and the Department of Environmental Protection handles WQPC credits. Either way, bring construction details, reservoir depth and a maintenance plan to the first meeting.

Resin Rock supplies the materials and does not install them: UV-stable binder, natural stone blends, trims and the Rock Crete permeable sub-base, with technical data sheets for the City Engineer or the county reviewer. We train and approve installers and can usually connect you with one within 24 hours through find an installer.

Before you specify permeable resin-bound in Silver Spring and Takoma Park

Confirm whether the address is inside Takoma Park or in unincorporated Silver Spring.
In Takoma Park, ask the City Engineer whether resin-bound will be considered, since the credit policy names porous concrete, porous asphalt and pavers.
Design at least 12 inches of stone reservoir to avoid a reduced Takoma Park credit.
Resolve the geotextile detail between the City credit policy and MDE Chapter 5.
Protect tree roots and check tree permit needs before excavating.
Submit Takoma Park credit applications by April 30.

Common questions about permeable resin-bound in Silver Spring and Takoma Park

How much can permeable pavement cut my Takoma Park stormwater fee?

Up to 50% of the original fee, which is the program's cap across all credits combined. The credit is calculated on the impervious area your facility treats, and the City may reduce it if the stone reservoir is under 12 inches deep. Applications received by April 30 apply to the billing year that starts July 1.

Will Takoma Park accept resin-bound surfacing for the credit?

The City's policy names porous concrete, porous asphalt and interlocking concrete pavers, so resin-bound is not listed. That doesn't rule it out, but it means the City Engineer decides. Bring the reservoir design, product data and a maintenance plan, and get an answer before installation rather than after.

I live in Silver Spring. Which rules apply to me?

Most of Silver Spring is unincorporated Montgomery County, so the county's Water Quality Protection Charge credit and RainScapes rebates apply, and development goes through the Department of Permitting Services. Takoma Park's fee and credit apply only inside the city limits. Check your tax bill or the county's WQPC lookup tool if you're unsure.

Official sources for Silver Spring and Takoma Park

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 Silver Spring / Takoma Park, MD