Revitalization and Development Strategy Rainwater Gardens/Bioswales revitalization and development strategy
Rainwater gardens (also know as bioswales or vegetated swales) are a form of bioretention that is used to capture and filter or evapotransporate stormwater. Within the study area, rain gardens shall be used for this purpose but detailed in a manner consistent with the town character and streetscape. Recommended Rainwater Garden details: ••
Select plant species native to Maryland and the Piedmont physiographic province.
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Choose plants that are tolerant of well-drained conditions, periods of drought, and periodic inundation, depending on the hydrologic design of the stormwater practice per MDE regulations.
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Select shade tolerant, partial shade, or full sun tolerant species based on site location, orientation, and proximity to tree cover and buildings.
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Consider maintenance and management (weeding) when designing, and allow for access needs.
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Consider plant height at maturity, and include consideration for sight lines (e.g., vehicular and pedestrian), safety and security, access to sidewalks, and overhead height restrictions.
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Design for complementary mixtures of foliage to provide interest and contrast in form, texture, and color; select plants that provide diverse seasonal color, texture, and fragrance.
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Along the street edge or where ground floor retail is located, trees shall be limbed to eight-feet clear for visibility and safety.
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Select flowering species that attract wildlife, including hummingbirds, skippers, moths and butterflies, songbirds, and additional pollinators.
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Design for a meadow-like mixture of herbaceous plant texture, height, and color with some groves of small– medium height trees as appropriate to space and design constraints.
credit: www.nevuengan.com
Photo 4.13 Rain Garden, Brisbane City Hall, CA
credit: www.sitephocus.com
Photo 4.14 Bioretention, The Meriwether, Portland, OR
credit: the pearl district guide (www.flickr.com)
Photo 4.15 Rain Garden, Portland, OR
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In this more organic/natural arrangement, plantings are typically free-form but include grouped species. Plant shrubs in groups of three–five of the same species and plant herbaceous plants in groups of five–seven (or more for large areas) unless a more random planting arrangement is desired. *All streetscape improvements are subject to SHA approval.
credit: Portland Urban Condos (www.flickr.com)
Photo 4.16 Rain Garden, Portland, OR
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Greater Upper Marlboro Revitalization and Development Strategy
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