1. Design innovation
The project seeks to instill the importance of habitat restoration among the visitors to the site. In order to achieve this objective, the project access to natural habitats by locating all the program within the artificial mound. The mound, which is created by excavated earth, incorporates slopes that channel water through different filtration ponds. The building form merges with the surrounding landscape and acts as a massive water filtration system to educate visitors about their natural surroundings. The land building filters ocean water and grey (waste) water using both mechanical and natural systems ( gravity). These systems are made accessible to visitors by locating them in the public areas such as the lobby and habitable roof landscape. Water is pumped up to the roof and then migrates down through a series of filtration ponds that re-create aspects of sub-tidal ecologies such as sand and rock substrates.
2. Regional /community design
Middle Harbor Shoreline Park is a component of the waterfront initiative developed by the San Francisco Bay Conservation & Development Commission ( BCDC) and the Port of Oakland. The master plan developed by the Port aims to open up inaccessible waterfronts to the public and enhance marine habitats. Our project proposes public spaces and landscape improvement elements that serve as habitats for birds and marine species, which Follow the spirit of both the Port’s master plan and BCDC’s regulatory mission. Improved Middle Harbor Shoreline Park will have a tremendous impact on the nearby community in terms of increased public transportation and mobility. By minimizing the built form on the ground the project maximizes outdoor recreational space on the site. In addition to engaging the community through educational outreach, the project provides an important recreational component and provides spectacular views of the Bay and Oakland for residents of the nearby neighborhood of west Oakland.
3. Land use & site ecology
The Bay Area suffers from deteriorating water quality, which increasingly endangers marine ecologies and overall biodiversity in the region. This project is dedicated to improving water quality around the site and restoring endangered species by providing new environments in the habitat pools located in both the exterior and interior of the building. The project provides habitat pools for the restoration of a broad range of species, including Delta Smelt, Steelhead Trout, Tidewater Goby, Coho Salmon, California Freshwater Shrimp and Black Abalone. The walk-able green roof consists of filtration ponds for ocean water and grey (waste) water. The filtration ponds for ocean water mimic artificial wetlands. They consist of filtration media such as aggregate and sand beds coupled with artificial oyster and eelgrass habitats to accelerate the filtration process. The first stage of filtration pond has a combination of aggregate bed and oyster habitats since rocky beds are suitable for oyster habitats. The second stage consists of a sand bed, which serves as an ideal habitat for eelgrass. Grey water filtration ponds use a subsurface filtration system consisting of native plants such as Koeleria macrantha, Woodwardia fimbriata and Baccharis pilularis. The building minimizes its footprint by locating programs underground and providing a planted, habitable roof. The paved areas are low SRI and permeable to minimize stormwater runoff and heat island effect.
4. Bioclimatic design
Oakland falls under California Climate Zone 3 with 2909 HDD ( heating degree days) and 128 CDD ( cooling degree days). Even though heating demands are higher, winters are mild enough to have less dependence on mechanical heating. The building’s planted roof provides insulation up to R38, which meets the targeted criteria. The building also benefits from the surrounding earth, which acts as a thermal mass for its heating and cooling needs. The skylights are designed to face south to provide maximum passive solar heat gain during winters. These skylights are also a source of daylighting. The building has an opening on the lower level facing west (prevailing wind direction) that acts as an air inlet. The operable opening on the top produces a stack effect for exhaust of stale and hot air.
5. Light & air
As most of the program is located below ground to fulfill project objectives, providing natural light and air in the interior was a primary challenge of this project. Oakland has dry bulb temperature of 80 and wet bulb temperature of 64. Based on the data from building energy consultants, the building implements strategies such as passive solar heating to reduce artificial heating needs and night flushing using earth as a thermal mass to reduce artificial cooling. The skylights constitute 3% of the total floor. This amount of well-insulated skylights is optimal for the day lighting needs in this area. Since the program is distributed on a single floor plate, all the areas have access to direct daylight and ventilation. Most of the skylights are operable as they also act as outlets for hot and stale air. The air inlets are located on the lower level towards the windward direction (west). The fresh air comes in and stale air rises up due to the stack effect created by opened skylights.
6. Water cycle
One of the main objectives of the project is to incorporate innovative ocean and grey water purification systems. These systems are tested in the water filtration pools located on the planted roof. The estimated water usage of the project is 9,900 gallons/day, which includes water used in toilet fixtures and the kitchen sinks in the cafe. The project uses low flow fixtures, saving about 77% of the water compared to the average building. Grey (waste) water filtration ponds use a subsurface filtration system before recycling the water for irrigation and uses suitable for grey water. The grey water is incorporated in an aquaponics system where nutrients are extracted and supplied to the surrounding landscape as fertilizer. The stormwater is recovered on site and used for landscaping and filtration processes in the building. The roof includes a planted portion (35,830 sq.ft) with a runoff coefficient of 0.17 and permeable pavers (3,230 sq.ft) with a runoff coefficient of 0.2. The total runoff comes to 803 cf. A 800 cf capacity storage tank is provided on site to manage the storm water.
7. Energy flows & energy future
In addition to the passive systems, this project relies on geothermal heating and cooling to achieve desired comfort levels. The estimated annual energy consumption is 330,801 kWh. This estimate is based on the assumption that building uses high efficient systems and LED lighting. The project uses onsite photovoltaic arrays to offset the amount of energy consumed. The proposed solar panels are adjustable and can meet optimal angles in different seasons: 28° in winter, 52° in spring and fall, and 76° in summer. The total area of PV arrays is 4,160 s.f. which is estimated to generate 321,813 kWh per annum.
8. Materials & construction
Fiber reinforced polymer (FRP) is the primary material used in this project. FRP is a composite material that consists of laminated fibers and resin polymers. FRP was chosen due to its durability, strength, resistance to corrosion, and light-weight properties. The construction system consists of repetitive vault structures for both the roof and foundation. Based on inputs input from structural engineers. The vault system is used for the foundation to achieve higher strength and material reduction. Each vault is divided into 3 FRP panels for easy manufacturing, transport and assembly. The building structure requires 30 vaults for the roof and 30 for the foundation. The panels can be manufactured at the facility located in Napa and transported to the site via barge. The entire structure is assembled using 180 panels.
9. Long life, loose fit
The geometry of FRP substrate on the floating structure is optimized to promote underwater habitats for marine species. Over the time this substrate becomes artificial reef that improves the biodiversity of the surrounding area. The floating structure is designed so that multiple such structures could be constructed and deployed to multiple sites throughout the bay.
10. Collective wisdom & feedback loops
This studio project was unique as the design process included multiple workshops with building industry experts. Through this design, we are attempting to restore deteriorating ecologies by natural and mechanical systems which would have been difficult to achieve without the collaboration with other industry experts. We got the benefit of collaborative team of architects, engineers, naval architects, marine biologists and fabricators.