Watercycle: A Vertically Integrated Stormwater and Bike Lane System

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.

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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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