Roslyn Pl. and New Haven Pl. Bioswale
Roslyn Pl. and New Haven Pl. Bioswale
Roslyn Pl. and New Haven Pl. Bioswale
Where is it located? It’s visible along a small trail that starts at the cul-de-sac between New Haven Place and Roslyn Place. As you walk the trail , watch for this bioswale alongside the trail.
What’s special about this place? This low place alongside the trail looks like a grassy lawn in the forest, but it’s really a bioswale. Bioswales are a low-cost, high-value way to treat stormwater runoff flowing from a neighborhood like Roslyn Place. The grass cover mimics natural processes and improves water quality.
About Bioswales
Bioswales are shallow, landscaped ditches designed to filter out sediment and other pollutants out of runoff as they move water from one point to another. Basic bioswales are a gently sloping ditch planted with grass which are designed to slow the water down enough to allow sediment to settle out. Some newer bioswales have a layer of prepared soil (sand, soil, and compost), with sand, crushed rock, and gravel underground, and are planted with hardy native plants that can tolerate both wet and dry conditions. After the runoff has been filtered through plants and soil, treated water flows downstream.
Water Quality Benefit: Bioswales help improve water quality by slowing and filtering stormwater. Living material in the plants and soil captures and biologically degrades pollutants, while absorbing some nutrients, but generally does not treat dissolved metals.
Water Quantity Benefit: When possible, some bioswales are designed for infiltration. In areas where the soil allows water to soak in, bioswales slow the speed of the runoff to reduce flooding, while recharging groundwater. The plants in bioswales also soak up some water which then evaporates during the growing season.
Drains 3.6 acres or a little over 2 1/4 square blocks.
Where does this stormwater runoff come from? Stormwater at this site comes from about 3.6 acres (2.25 blocks) of homes, yards, and streets of Roslyn Place.
Where does this stormwater runoff flow next? Runoff from this site flows into Fever Creek and then into Whatcom Creek.
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This bioswale along the trail between New Haven Place and Roslyn Place, looks a bit like a lawn. It also keeps the trail dry and protects water quality.
This vegetated ditch is a functioning bioswale which moves water and chemically and biologically treats polluted stormwater runoff from Rosyln Place.
Stormwater drain pipes are everywhere. They keep water moving and prevent flooding. This shows runoff coming out of Rosyln Place neighborhood and into the bioswale.
At this Rosyln Place trail entrance, the storm drain inset into the curb marks a stormwater pipe connection along the trail easement.
Cottonwoods tower over trails in this area. They are high-value habitat trees, effective soil stabilizers, and keep water and forests cool through shading.
This bioswale is long and linear with vegetation that slows the flow of runoff and causes particles to settle into the soil.
Bioswales are vegetated, landscaped depressions designed to capture, treat, and infiltrate stormwater runoff. Note shallow design and mix of compost and soil.
