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When public improvements require stormwater management, four options are potentially available to meet SWMM requirements in the right-of-way depending on the specific characteristics of the project. Projects can include a combination of these options.

By approving the Central City 2035 Plan, Council enacted a new ecoroof requirement that applies to most buildings in the Central City Plan District. Here, we provide clarification for how the requirement of CC2035 relates to the Stormwater Management Manual.

This guidance can help applicants and designers understand how the City's Stormwater Management Manual requirements apply to construction projects in the public right-of-way.

The 2020 Stormwater Management Manual (SWMM) became effective Dec.14, 2020. The manual sets City policy and design requirements for stormwater management on all development, redevelopment, and improvement projects on both public and private property in Portland.

Basins collect rainwater to control flooding and prevent erosion. They are an attractive way to manage the rain on your property and can add interest to your landscape. They are most suitable for large, open spaces. 

Concrete-walled planters are a permanent landscape solution. They can be designed to accommodate the shape and size of your space as well as soil type. They are a good choice for properties where space is limited.

Registration is required for all City-owned UICs, including those in the right-of-way or on City-owned properties. Find the forms and process to register or decommission sumps, soakage trenches, hybrids, or other facilities that infiltrate stormwater below ground.

A drywell is a long-term and low-maintenance way to manage the rain on your property. It may be a good solution for a property where erosion and flooding are a frequent concern. Drywells are underground, so they will not change the visual appearance of your space.

If you want to manage stormwater safely on your property but do not want to give up valuable landscape area for a rain garden or other solution, a soakage trench may be the right fit for you. Soakage trenches are hidden underground and do not require any surface area after installation.

Rain barrels are an easy way to collect, store, and use the rainwater that falls on your property. Keep roof runoff to use later to water your lawn, garden, or indoor plants.

If your property has large paved areas, permeable pavement could be a good solution for managing runoff. Permeable pavement allows rain to soak into the ground. It is suitable for use with driveways, parking lots, and patios.

At the end of the 2-year maintenance warranty, public works permit applicants must deliver to the City well-established and functioning stormwater management facilities. Environmental Services offers applicants two options for maintenance during the warranty period.

Ecoroofs are an attractive way to manage the rain on your property without altering the landscape. An ecoroof, also known as a green roof, can be a good solution for properties with little or no yard or patio space.

Roof gardens are an innovative way to manage the rain on your property. Roof gardens are thicker green roof systems that manage rain but typically also provide access with benches and pathways.

Portland’s Municipal Separate Storm Sewer System Permit, or MS4 permit, regulates discharges from the City’s municipal stormwater system, which is separate from the sanitary sewer system. Learn more about the City's MS4 permit on this page.

The City of Portland is updating the Stormwater Water Management Plan and Monitoring Plan. The public commented on the plans before submission to the Oregon Department of Environmental Quality for approval. The comment period was open from Sept. 1 to Sept. 30, 2022.

Thank you for managing the rain on your property! Follow these important steps to make sure your rain garden, basin, planter, swale, disconnected downspouts, or other stormwater management facility keeps working safely and as designed.

Residential rain gardens are a natural way to manage the rain on your property while adding beauty to your landscape. They can be a good solution for flatter spaces where the soils allow water to quickly and safely soak into the ground.

Trees are a readily available, natural way to manage the rain on your property. Trees are easy to plant, low-cost, and most property owners can do the work themselves. Learn about the types of trees best suited for your property before planting.

Use the guidance below to determine if your right-of-way project triggers requirements of the 2020 Stormwater Management Manual.

Stormwater management solutions such as rain gardens, rain barrels, ecoroofs, or trees can help manage the rain on your property to protect our rivers and streams. Learn more about the different stormwater management solutions here.

Where soils soak up water and yards don’t have steep slopes, disconnecting your downspouts to direct water from your roof to your yard can be a simple, inexpensive, effective, and easy way to manage the rain on your property.

Portland’s Water Pollution Control Facilities Underground Injection Control (UIC) Stormwater Permit regulates UICs that collect and manage runoff from public spaces. The City prevents pollution to groundwater through these structures by using stormwater management best practices. Learn more.

Environmental Services has an ongoing monitoring program to test and confirm the performance of stormwater facility designs in the Stormwater Management Manual. Learn more about this program and find monitoring reports on this webpage.

Portland may be the Rose City, but we’re just as well known for our rainy weather. We get an average of 37 inches of rain each year. You might wonder, “where does all that rain go?” Read on to learn how rain becomes stormwater, and how Environmental Services manages the challenges it causes.