WaterCycle:
A vertically integrated stormwater and bike lane system Jessi Flynn
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Water-Cycle
Thesis Research and Studio Fall 2014 and Spring 2015 Instructors: Nina Chase and Ellen Merritt
Location: Boston, MA: Back Bay and South Boston Summary: Decentralized stormwater/sea level rise combined with multi-modal transportation systems in an urban environment.
Bicycle Crashes Police recorded 2009-2012
Radar maps showing impervious surfaces of Boston and Massachusetts. Impervious Surfaces: Roads, Sidewalks, Driveways, Parking Lots, Roofs, Compacted Gravel Cycletracks Planned by City of Boston over next 30 years
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Natural water cycle
Bioremediation: Pollutants carried in urban stormwater can be broken down or removed through bioremediation using soil bacteria and plants. Volatilization of chemicals
Hg(0) Hg(0)
Hg(0)
Hg(0) released as naturally occurring mercury vapor.
Mercury
Hg(0)
Hg(0)
Urban water cycle due to impervious surface runoff
Bacteria
Hg(II)
Hg(II) Hg(II)
Hg(II)
Hg(II) + Ocean (salt water) = MeHg - highly toxic bioaccumulator in wildlife.
Hg(II)
Degradation of fuels, solvents, and herbicides by soil bacteria. Solvents Fuels Bacteria Bacteria
Designed urban water cycle that captures, uses, and returns water to the natural water cycle.
Bacteria
Nutrients for plant
Root
Herbicides
Bacteria digests Carbon for bacteria Fuels, Solvents, Herbicides
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Landscape Urbanism:
Shifting From Parcel to Ecological Scale
Centralized Infrastructure and Parcel Based Planning: Water removed as waste to city infrastructure
Linking built, decentralized stormwater treatment into transportation networks that mimic natural watershed scale.
Natural Watersheds (blue): Streams and rivers serve as water collectors and conduits.
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Bike Network (orange) as Urban Watershed: Streets and cisterns serve as water collectors and conduits.
Decentralized Ecological Scale Planning : Water connections pool water as resource using public street space
Integrated Watershed as Combination of Built and Natural Networks
Stormwater Analysis
In a typical 1� rainstorm, this study area discharges 500,000
gallons of water carrying contaminants directly to Boston Harbor.
90,000 gallons
400,000 gallons
Impervious Surface Catchment Area Site Catchment Area Catch Basin Pipe Stormwater Outfall Streets Buildings Site
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Capture and Reuse of Stormwater Runoff
1. Collection: Water runs off streets, into cistern through curbcuts.
2. Retention: Stormwater stored in cistern.
3. Treatment: Water reused for street tree and planter irrigation. Filtration through soil is critical step in green infrastructure to breakdown pollutants. 6
Existing system: Water is collected off streets, and piped directly to Boston Harbor and rivers, carrying pollutants directly into water.
Boston Harbor
Infiltration of Stormwater Runoff
1. Collection: Water runs off streets and sidewalks into cistern through curbcuts.
2. Retention: Stormwater first flush captured and infiltrated by raingarden, overflow to porous bottom cistern to infiltrate. 3. Treatment: Filtration through raingarden, infiltration through subsurface soil breaks down pollutants, recharges groundwater levels.
Groundwater
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Innovation District Design: BioBuoys
Buoys in harbor water
Floating d`ock
Existing stormwater outfall
Planter boxes irrigated with captured stormwater
Buoys floating in stored stormwater
Plant palette includes plants known for phytoremediation properties as well as harsh coastal and street environment tolerance.
Recessed downlighting on all sides
Curb cuts to convey stormwater to underground cisterns
Plant Palette Acer rubrum Red Maple
Populus tremuloides Quaking Aspen
Juniperus comunis Juniper
Plant Images: Missouri Botanical Garden
Nepeta racemosa Catmint Image: NorthCreek Nurseries
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Existing stormwater outfall
Buoys float in stormwater collected from the street in an underground cistern. As the buoys rise and fall, colors indicate the level of the water. Water collected in the cistern is used for irrigation of planters and street trees. The infiltration of the water through this method removes many stormwater contaminants. The buoys in the Harbor water are the reminder that the water is connected. What we allow to drain into our catch basins, we put directly into our Harbor.
Wood boardwalk
Angled entry allows cyclists to pull in, dismount
Concrete one way cycletrack
Oaks for biodiversity Red maples for water uptake Quaking aspen for pollutant breakdown
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Back Bay Design: Water Way
Curb cuts allow runoff to enter raingarden at street level. Metal grating covers curb cut Steetl grating over runnel allows cleanout access
Raingarden widths widest between existing trees
Raingardens narrow to allow pedestrians and cyclists sp
Plant palette includes salt tolerant raingarden plants suited to urban streets and a range of water tolerance.
Plant Palette Rudbeckia maxima Coneflowers
Liatris spicata Blazing Star
Deschampsia ceptiosa Tufted Hair Grass
Aster novae-angelica New England Aster
Oenothera spicata Sundrops
Andopogon gerardii Big Bluestem
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Plant Images: NorthCreek Nurseries
pace to pause
At grade pedestrian crossings connect sidewalk to street parking, allow raingarden crossing and interaction.
Existing trees to be preserved
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