Walnut Creek Wetland Center
Green Design Features

Sketches provided by Erin Sterling of Frank Harmon Architect PA

Street View Site Plan Perspective Floor Plan

Walnut Creek Wetland Center - Site Features

Site Features
Porous parking stalls
Stalls are made of porous concrete that allows water to penetrate through the material and filter through a sandy base before reentering the site.
Bioretention Areas
Bioretention areas are located in the parking lot and along the building's north face. Rainwater runoff from the parking lot is collected and filtered slowly so that water is clean when it enters the wetlands below the lot.
Building "Floats" on Timber Pilings
The timber pile foundation minimizes site disturbance and allows water to flow underneath the building. Timber piles are a carbon positive, renewable material and have a low "embodied energy" compared to other foundation materials and systems. Typical concrete footings and foundation walls would be heavy and act like a dam on the sloping site while timber piles allow the building to have minimal impact. Maintaining the natural topography of the land allows for the natural flow of water from the northern, more urban portion of the site to the southern, forested area with delineated wetlands and stream.
Minimal Site Impact
Building location is as far north as possible to conserve forest trees and provide a welcoming invitation to visitors to experience the wetland beyond, while providing the required parking and fire truck access.
Green Footprint
The building footprint is narrow and oriented east-west to maximize passive solar control and access to north daylight. This conserves energy related to interior heating, cooling, and electric lights.