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The City of Portland, Oregon

Environmental Services

working for clean rivers

Phone: 503-823-7740

Fax: 503-823-6995

1120 SW 5th Ave, Suite 613, Portland, OR 97204

More Contact Info

Healthy Flow-Thru Planter

The City requires that vegetated stormwater facilities have at least 90% plant coverage to ensure stormwater treatment functionality and encourage the many environmental benefits these features provide.

Pervious Pavers / Porous Asphalt

Pervious pavers and porous asphalt are great alternatives to traditional pavement. It can be driven and parked on, but it also allows rainfall to infiltrate into the ground. Routine sweeping or vacuuming removes sediment that builds up in void spaces.

Vegetated Swales & Check Dams

Swales convey runoff from its source to an approved destination. The rock “check dams” help increase the retention time of stormwater, reducing the impacts of “flash” flows to the City’s systems and our rivers.

Manufactured system with maintenance issues

Check cartridges and measure sediment levels annually. This StormFilter cartridge has become dislodged and should be re-positioned. More than 4” of sediment at the bottom indicates needed maintenance.

Wet Detenion Ponds

For some commercial and industrial sites, wet detention ponds are used to hold stormwater for long periods. In time, the bottom of the pond may require dredging if its capacity to retain water becomes limited.

Sediment and debris at curb inlets

Inlets build up excess sediment and debris which prevents stormwater from flowing into the facility. For proper maintenance: sweep away dirt and trash, and cut back excessive vegetation to remove blockages.

Infiltration Basin

Infiltration Basins (or rain gardens) prevent stormwater from taxing the public stormwater system. Maintaining a healthy amount of plants is visually appealing and ensures these facilities retain their infiltration capacity.


Well-maintained ecoroofs provide multiple benefits to a community. They reduce peak flows to combined sewers, provide pollinator and wildlife habitat, and reduce the urban “heat island” effect.

Poorly maintained flow-thru planter

This neglected planter has a lack of vegetation. Plants filter out pollutants and promote evapotranspiration.