Environmental Services is designing improvements to about 2,760 feet of ditches along SW Stephenson Street between SW 35th and SW Boones Ferry Road. Work will begin in summer 2015.
Ditches on SW Stephenson carry stormwater runoff from the street directly to Tryon Creek and its tributaries. The fast-moving water causes erosion and carries pollutants washed off streets.
This project will plant swales with a combination of grasses and low-growing plants. The vegetation will help protect the channel from erosion and may help reduce stormwater pollutants. As part of the project, the Portland Bureau of Transportation will add four-foot wide, paved shoulders.
Environmental Services is working with citizens and neighborhood groups on project plans including impacts to trees in the project areas.
The Fanno-Tryon Watershed Management Plan identified these improvements as a way to improve drainage and pedestrian safety and protect water quality. Over one-third of the roads in the watershed are paved and have no curbs. Ditches border most of them.
Tree trimming and removal
In preparation for the project, work crews will trim and remove some trees, shrubs and hedges in the public right-of-way. That work will start in March to avoid bird nesting season. The city’s contractor will remove tree stumps and trim any additional trees necessary during construction.
Work crews will install plants in and around the new swales when construction is complete.
You may see crews in the area this winter marking the right-of-way lines, outlining the work areas and flagging trees that will be removed. Please leave the stakes, ribbons and other markings in place for use during construction.
Construction schedule and traffic controls
Construction is expected to begin this summer. There will be some lane closures, with flaggers directing traffic when necessary. The contractor will maintain access to homes and neighborhood streets. We will continue to be in touch as we get closer to construction.