Doan Brook Watershed Projects

Learn about partnership conservation and restoration projects; currently in-action, as well as completed projects with results.

Shaker Parklands Bioswale, 2011

Tuesday, November 01, 2011

If you've walked, driven or bicycled along South Park Boulevard in Shaker Heights after a rainfall, you may have noticed standing water along the muddy edge of the road. The DBWP, with partners Northeast Ohio Regional Sewer District, Burning River Foundation and the City of Shaker Heights, chose this site as a demonstration for a new remedy to stormwater challenges.

Site along South Park Blvd. by Lower Shaker LakeStormwater runoff leads to sedimentation in Shaker LakesStormdrain siteMapping out bioswale area with marking paintA three tiered trench is dugView of trench looking upstream along South Park
Bioswale drainage ties to stormdrainClose-up of stormdrainA center pipe is installed, holes face downFabric sleeve covers center pipeGravel fills the deep trench over pipeTrench soil is redistributed into a landscape feature
Ohio native plants are laid outAn assortment of  sedges and ferns lend biodiversityCompleted bioswale, 2011Stone top layer assists with drainage

The goals of the Shaker Parklands Bioswale Demonstration were as follows:

  • Demonstrate a green infrastructure solution to a chronic source of sediment to Lower Shaker Lake
  • Install the green infrastructure, in this case a bioswale, in a publicly visible location
  • Provide education/outreach to accompany the bioswale
  • Create a long-term plan to maintain the form and function of the bioswale

After an RFP process, the DBWP hired landscape architect, Jim McKnight & Associates, to install a 100 foot bioswale to rectify sediment loading to Lower Lake from a faulty stormdrain.  The site is located at the edge of South Park Boulevard and the Shaker Parklands (Doan’s riparian corridor), between Larchmere Blvd. and Coventry Rd., in Shaker Heights.

McKnight and Associates designed the bioswale to receive water from South Park Blvd, not only to address sediment loading but also to filter and purify runoff.  The swale is a two-tiered trench, with a perforated pipe in the bottom trench.  With perforation side down, the drainpipe was covered with a “sock,” which is the last stage of filtration.  The water is first received by hydrophilic native plants, then a layer of specialized soil, a layer of mixed small stones and a layer of mixed large cobbles. The water that does reach the underlying drain, is cleaner and of a lesser volume.  Only at this point does the stormwater enter the original storm drain on South Park.  Because we were able to create a long-term maintenance partnership with student volunteers from Hawken School, the City of Shaker approved the use of a much more biodiverse plant scheme for the swale.  This biodiversity will provide additional habitat benefits, such as pollination and healthy soil profiles.

A temporary sign was placed in October, 2011, at the bioswale during construction to educate the public about the disruption and, more importantly, about the green infrastructure demonstration.  The sign will remain until the Partnership coordinates the design and installation of the permanent sign in early 2012.  This permanent sign will explain the benefits of green infrastructure solutions to a known impairment to Lower Lake, Doan Brook, and Lower Lake water quality: sediment.

We are deeply thankful to Hawken School, whose upper students committed to maintain the bioswale on a monthly basis, now and in the future.  Thus, instead of the monoculture of grass, the Shaker Parklands have been enriched with native Blue Wood Sedge, Variegated Sedge, Wide-leafed Sedge Grass, Toothed Wood Fern and Rose Mallow.