Turning Stormwater into Habitat
- Breanna Gunderson
- 2 days ago
- 7 min read
Wildlife Ponds, Rainwater Gardens, Bioswales, Urban Wetlands, and Stream Revitalization
Rainwater runoff can cause puddles, pools, ponds, streamlets, slicks, rivulets, rivers, bogs, and erosion. Raw runoff going into the stormwater drains can carry pollutants and divert water away that can be beneficial to your landscape.
A big part of the work we do at Urban Rewilding has to do with -all-of-the-rain-water. Because here in Portland, we get so so so much. It's raining right now as I'm writing this, and it has been all week.
We focus on developing wildlife pond and wetland habitats that depend on all that water, creating natural features that best fit into the space—disconnecting downspouts to be routed into rain gardens, dry riverbeds, wetlands, and revitalizing both year-round and seasonal streams.
Whether your yard is steep, shady, clay-heavy, or sandy, there’s a stormwater feature that can fit. We're here to transform your rainwater from a problem into a lush habitat.
Wildlife Ponds: Shallow, Lush, Full of Life
A wildlife pond is a miniature wetland ecosystem. Ponds slow stormwater from roofs and paved areas, filter nutrients and sediments, and create refuge for frogs, dragonflies, birds, and pollinators.
Even a small backyard pond can be a sanctuary for Pacific chorus frogs and salamanders while supporting insects and birds that keep your yard alive and balanced.
Where It Works: Ponds do best in low-lying areas where runoff naturally collects or can be directed to with gentle swales. Clay in the soil is ideal. Full sun to part shade works well, though shaded edges allow amphibians to escape the summer heat.
Avoid placing ponds too close to foundations—10 feet or more is recommended for safety.
Building Tips and Habitat Enhancements
Excavation & Base: Dig 12–24 inches at the center with gently sloping sides.
Rocks and Logs: Add partially submerged logs and flat rocks along the edge to provide hiding spots for amphibians and basking areas for insects and birds. A few large boulders help slow water flow and provide perching sites.
Planting: Use dense native sedges like Carex obnupta along shallow edges to stabilize soil and shelter frogs. Douglas spirea and salmonberry along the perimeter offer cover for birds and pollinators.
Overflow: Direct heavy rain overflow into a nearby rain garden or dry riverbed to prevent erosion. Line spillways with river rocks to slow water.
Project-Specific Notes: We began work on this wildlife pond in SE in late winter of 2025.
This project was part of several ecosystem installations we completed with the homeowner between January and March 2025.
We planted forests in the front yard, the homeowner seeded prairies in the back, and this peak project, a wildlife pond on the side of the house. We added thimbleberry, Coolie's hedge nettle, nootka rose, pacific nine bark, douglas spirea, camas, tufted hairgrass, spreading rush, yellow monkey flower, coltsfoot, lady fern, salmonberry in and around the pool.
We used Columbia willow to create a willow dome play area. We also built a fort, placed logs around the pool for observation, and turned the area into an interactive nature space for their young children.
I revisited the project the summer after the installation, and the toddler was just learning how to talk and already knew some of the names of the native plants from playing out there and having his parents teach him.
This space will grow with the children as the living willow fort transforms from a few wispy twigs into a secret fort; the grasses will grow taller, and the fruit will ripen at the same time each year.
The trees will grow so they are always the perfect height to climb. The land will watch the children grow and remember all the times they will have together.
It's a really special place, and we can't wait to return in January 2026 to complete a shrubby meadow on the back slope.
Lined Pumpless Ponds
For sandy or highly drained soils, a lined pond can hold water where natural infiltration would quickly drain it. These ponds are easy to maintain, requiring only occasional topping off in summer. They can also be an incredible wildlife habitat.
Why They Work, even a shallow pond supports frogs, dragonflies, and pollinating insects. The liner ensures water stays long enough for breeding amphibians, while overflow channels prevent flooding into structures.
Construction Tips
Use UV-stable EPDM liner or bentonite clay for a natural, wildlife-safe seal.
Place sand or geotextile fabric under the liner to prevent punctures.
Create shallow shelves along the edge to provide access for marginal plants and wildlife.
Add partially submerged logs or stumps to provide shelter and microhabitats for invertebrates.
Planting and Habitat: Instead of rigid plant lists, think of zones: submerged plants like wapato and umbrella plant for insects, shallow-edge sedges and rushes for amphibians, and shrubs like salmonberry and Douglas spirea along the upland edge.
Evergreen huckleberry and salal create year-round cover and food for birds. Pacific waterleaf and redwood sorrel offer edible greens and dense ground cover for small mammals.
Project Considerations: This project was completed in September 2025. We built this pond at the lowest point of the backyard. It also has a stormwater runoff pipe that flows into it.
Throughout the winter, the water flows through the pond. It flows out to a dry riverbed planted with salmonberry, Pacific ninbark, red twig dogwood, and many other native riparian fruits, plants, ferns, and bushes.
All of the rainwater that flows through the sloped backyard collects in the low area. We used logs to build a salamander habitat in the center of the pond. We wanted a lot of sheltered space. After less than three months, Salamanders are living in this pond. A lifetime achievement award to me.
Although the planting appears sparse in the photo, it will develop into a dense, biodiverse, and fully functioning ecosystem within the next year.
Pump-Fed Flowing Ponds: Miniature Streams at Home
Some Portland yards can accommodate a small, flowing pond that mimics a stream, providing movement, oxygenation, and diverse habitats. Flowing ponds are particularly engaging for wildlife—frogs, birds, and insects all use moving water differently than still water.
Design Tips
Use a low-energy recirculating pump to create a gentle flow.
Make channels shallow (6–12 inches) and meandering to slow water and mimic natural streams.
Integrate rocks, logs, and brush piles to create hiding and resting spots for amphibians and aquatic insects.
Plant and Habitat Integration: Plant edges densely with sedges and rushes to stabilize soil and provide cover. Riparian shrubs, such as red-osier dogwood, salmonberry, and Douglas spirea, offer perching, nesting, and foraging sites.
Shallow shelves with partially submerged logs give dragonflies, frogs, and water insects an ideal habitat.
Project Specific Note: We were able to do a lot of really meaningful work in this yard. It's a large double lot. Our first success was building large native planters out of wood to cover the asphalt. Instead of having it removed, we're going to allow nature to gobble it up.
Dry Riverbeds: Seasonal Streams That Work Hard
A dry riverbed, or bioswale, is more than decorative. It channels stormwater, filters pollutants, and supports wildlife, acting as a connective tissue between ponds, rain gardens, and wetlands.
Construction and Materials
Excavate a shallow channel 6–12 inches deep with a slight slope.
Incorporate logs, flat rocks, and small boulder clusters to provide shelter for amphibians and insects and slow the flow.
Add mossy logs or brush piles along edges—these are perfect resting sites for small mammals and birds.
Planting and Wildlife: Plant moisture-loving species like sedges, tufted hairgrass, and spreading rushes along the wet channel. Drought-tolerant shrubs, such as kinnikinnick and creeping Oregon grape, along the upper edges provide berries and cover. The rocky edges offer nesting opportunities for ground bees and shelter for frogs and salamanders.
Portland Considerations: Dry riverbeds are a common feature in yards, often accompanied by seasonal sheet flow from roofs or impervious surfaces. They’re also excellent in hilly neighborhoods, where stormwater might otherwise create erosion problems.
Rain Gardens: Beautiful, Functional, and Edible
Rain gardens capture runoff from roofs and paved areas, letting it soak into the ground naturally. In Portland, rain gardens can handle the winter deluge while creating habitats for pollinators and providing food for people and wildlife alike.
Construction Tips
Dig a shallow depression, typically 6–12 inches deep, and allow for a 24-hour drainage period.
Use well-amended native soil or a mix of compost and loamy topsoil to retain moisture.
Include a clear overflow path for storm events.
Planting and WildlifeNative shrubs like red huckleberry, salmonberry, and Nootka rose attract birds. Groundcovers like coastal strawberry and redwood sorrel feed pollinators and provide shelter for insects. Even small pools of temporary water support aquatic insects and amphibians during storms.
Portland Considerations: Rain gardens are ideal for compact urban lots and medium-sized yards where runoff from multiple surfaces collects. By incorporating native edibles and dense cover plants, rain gardens become a living, foraging, and pollinator-friendly ecosystem.
Constructed Wetlands: Water Filters and Wildlife Hubs
Constructed wetlands are multi-layered systems that filter stormwater while supporting abundant wildlife. Even a small backyard wetland can process runoff from multiple downspouts while providing habitat for amphibians, birds, and pollinators.
Construction Tips
Excavate multiple depth zones: a deep pool for submerged plants, a shallow shelf for emergent plants, and a wet meadow at the edge.
Layer gravel and sand to filter water naturally before it reaches loamy planting soil.
Add partially submerged logs and brush piles for amphibians and invertebrates.
Wildlife and Plants: Wetlands support the breeding of frogs, damselflies, and dragonflies. Birds feed on insects and berries along the edges. Logs and root tangles provide hiding spaces for small mammals, while riparian shrubs like Douglas spirea and red alder shade water and stabilize banks.
Portland Considerations: Backyard wetlands work best in low-lying yards with consistent stormwater flow. By mimicking the structure of natural wetlands, they create complex habitats for diverse urban wildlife communities.
Revitalizing Existing Streams: Healing Seasonal and Year-Round Waterways
Many urban streams in Portland are overrun with invasive plants, eroding banks, and poor water quality. Restoring these streams—removing invasives and planting dense native riparian vegetation—can dramatically improve habitat and water quality.
Construction and Planting
Remove invasive ivy, Himalayan blackberry, and reed canarygrass along banks.
Stabilize slopes with native sedges, rushes, and shrubs.
Incorporate logs, root wads, and boulder clusters to create pools, riffles, and cover for amphibians, birds, and small mammals.
Wildlife Benefits: Restored streams support breeding amphibians, foraging birds, small fish, and pollinators. They also stabilize soil, reduce erosion, and filter stormwater before it reaches rivers or wetlands.
Urban Rewilding Can Help
We’ve designed and installed hundreds of Portland stormwater projects, turning yards into thriving ecosystems. We know what works for local soils, hydrology, and native species. By integrating ponds, flowing water, rain gardens, wetlands, dry riverbeds, and restored streams, we create functional, biodiverse, and beautiful landscapes.
Our lifelong mission and passion is to create fully functioning PNW native plant landscapes in urban and suburban yards, forests, prairies, wetlands, ALL OF IT!!! I want all of that everywhere I look in this city, ASAP.
Contact us today for a personalized assessment of your rainwater system. Let us help your yard filter stormwater, support wildlife, and become part of Portland’s living watershed. With logs, boulders, native plants, and thoughtful design, we transform rainwater into habitat and backyards into thriving ecosystems.
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