© 2018 Allan Kapoor

Rendering by Kate Lenahan

PERFORMANCE METRICS

> Retention Capacity: 169 acre-ft

     (91% of local 100-Year Flood)

> Levee Height: 16 ft

> Sea Level Rise Protection: 4 ft

 

> Housing Units: 987

> % BMR: 1/3

> Residential Density: 51.5 DUA

 

> Public Space: 4.64 acres
> Vehicle Parking: 0.5 per unit

> Bicycle Parking: 1 per bedroom

 

> Light Industrial/R&D: 675,565 sf

> Office: 600,502 sf

> Commercial: 313,043 sf

Living with Water: A Floodable Coastal Residential Development

East Palo Alto, California

3-person team in UC Berkeley's urban landscape design studio

DURATION

8 weeks

SKILLS

Large-scale site planning/programming

Flood management infrastructure design

Hydrology calculations

Axonometric concept diagrams

(all graphics by Allan Kapoor unless otherwise noted)

TOOLS

AutoCAD

Illustrator

Photoshop

Rhino

CHALLENGE

Our study area is narrow strip of mostly undeveloped land, situated between a neighborhood of single-family homes and a bayside FEMA levee.

Given the neighborhood’s proximity to the Silicon Valley, residents face gentrification, overcrowding, and a lack of affordable housing.

The community also suffers from severe flooding and will face the brunt of sea level rise. The adjacent tidal marsh has great potential to act as a buffer, but San Francisquito Creek is channelized and prevented from dispersing sediment to support marsh accretion.

SOLUTION

My team’s proposal consists of almost a thousand modular units of housing built over bioretention ponds that store and filter stormwater.

The adjacent marsh acts as a buffer against sea level rise and is "grown” into a horizontal levee using a series of sediment dispersal techniques that use the stormwater to mimic natural processes.

The design reflects our belief that adaptive infrastructure can have a variety of social, environmental, and economic co-benefits. The marsh and retention ponds provide habitat for endangered species, a promenade along the levee acts as a backbone for the development, and a series of parks and recreation spaces serve as community amenities.

TEAM

MOVEMENT OF WATER

Stormwater runoff flows through East Palo Alto towards the development

Water is filtered as it flows through a series of retention ponds.

Pump stations drain the ponds and pump water into pipes running along the top of the levee.

Water drains over the levee and into the marsh through outfall pipes. Sediment placed at the outfalls mixes with stormwater and deposits in the marsh, mimicking bluff erosion processes, and forming the horizontal levee’s gradual slope.

GROWING THE LEVEE

Our design includes a horizontal levee, a gradual 30:1 slope populated with marsh vegetation, which acts as a buffer against wave action, reducing the need for a high floodwall.

We proposed a series of innovative sediment dispersal techniques to augment natural marsh accretion and fill in the slope of the levee over time without destroying valuable marsh habitat.

FLOODABLE HOUSING

The top of the levee doubles as a mixed-use promenade with a dedicated lane for commuter bicycle traffic.

Behind the levee, a finer fabric of two to three story apartments over bioretention ponds provides affordable and market-rate rentals.

Rendering by Kate Lenahan

Levee promenade with inset mixed-use and residential structures over bioretention ponds

INFRASTRUCTURE AS PUBLIC SPACE

A community center extends out over over ponds with an adjacent, floodable gathering area that invites people to observe changing water levels. Rain garden terraces expose these processes, and a floating soccer field allows residents to play on the water.

Rendering by Kate Lenahan