This aquarium is located in the city of Onahama, known for mackerel fishing, on the Pacific coast of Fukushima Prefecture. The site, at the tip of a pier within the port of Onahama, where fishing related plants and docks stands aside, is in the redevelopment zone with other projects such as shopping mall and ocean liner terminus. Although this pier itself is directly facing to the Pacific, the view of the ocean is not prefect considering other developments including land reclamation in front for housing and parks.
The central axis of the city of Onahama continues as a promenade and reaches to the Pacific at the east side of the site. For this, a boardwalk encircling the area is proposed to create beach side pedestrian circulation along with large green space intending the to be integrated seaside park. Barbecue corners, a floating theatre, and movable shops are proposed for the area. Mounds are to be made of soil excavated from the construction reflecting the image of waves. From the mounds, one can enjoy the commanding view of the Pacific. Also, this mounds hides mechanical equipment, staff parking, and other services facilities, with services such as barbecue kitchen and public toilets embedded within.
Opposite to this east side pedestrian circulation, vehicles enter from the west side of the site to the parking for the parking is shared with multipurpose event space located further west. The galleria with glazed roof connects these pedestrian and vehicular entry.
This galleria, bustled till late at night with a restaurant, museum shop, multipurpose hall and IMAX theatre, is also the main entrance for the entire complex. From this galleria, one can approach to the aquarium beyond the reflecting pool, that separates the complex in tow blocks.
The aquarium, with various exhibitions including main large tank, research facilities, maintenance and mechanical facilities, is connected with the galleria by two tubular corridors.
The purpose of this parti is to separate aquarium that requires 24 hour support for the fish from other functions so that the maintenance of the entire complex becomes easy to control and cost effective. Also, thatre complex could be used separately for the local community, contributing as a cultural focus of the area.
Aquarium is designed to be a massive curved volume with smooth metal skin, resembling sea mammals such as whales, dolphins and reminding fertile ocean life system. Where the volume intersects with the galleria has a sharp cut out covered with glass from which one can view various tanks and supporting systems inside.
This glazed opening is unique among typical aquaria since most of them are cladded with almost no openings due to its functional requirement. During daytime, this opening is closed with screen but in the evening when the screen is up, the main space within the aquarium called Ocean Atrium and support mechanisms that are usually concealed are lit up to be noticed from outside, providing a view of tank and fish swimming in the tank reflecting on the pool. This unique view will illuminate the port in twilight.
The most significant feature of the complex as an aquarium is its capability to provide border fauna of the Pacific ocean ashore the Fukushima Prefecture called Shiome, where Kuroshio, the warm current and Oyashio, the cold current meets. In the main large tank, warm water and cold water actually meets in this aquarium, enabling to exhibit realistic ecosystem model in large scale.
One can enter the aquarium from the second level of the galleria by the moving walks in the two tubed bridge. Dark space inside the tube resembles the beginning of the universe and the life with visual effects.
First exhibition right after one comes out from the tube is the Prologue occupying the edge of the aquarium. Located at the edge of the ellipsoid shell, this space extends vertically along curbed inner surface of the ellipsoid. The thesis here, floating in the space, is mainly the relation between the earth and the life. This exhibition of the life from its beginning finishes at the rocky tunnel which leads visitors to the next exhibit. Panoramic exhibit with full of natural light through the glass blocked skylight shows "rivers and coastlines of Fukushima", beginning in the mountains of Abukuma, the panorama exhibit runs through trees down to the coast of Fukushima. From this point, the space even expands to the triple height exhibit of "ocean corridor", where a lot of small tanks show scientific and experimental exhibits related to the ocean. Through the void space above, you can observe three large tanks above on the third floor. That is, Sea Otter tank of northern sea, mangrove tank of southern sea, and large tank of Shiome, the border sea. This point where one can command the view symbolizes Fukushima Prefecture, located on the coast where northern and southern sea meets.
The route runs through Kuroshio tank and Oyashio tank, to the spiral escalator projecting out of the ellipsoid in arc to the third floor. This spiral escalator takes you out of the building first, then into the large tank of the border tank. An acrylic tube of "border tunnel" cuts across the tank.
This border tank inhabits both northern fish and southern fish together. They usually cannot share the aquasphere due to the inhabitable temperature differences, but in this tank, with adjustment of water circulation and thanks to the density difference of warm and cold water, Shiome, the border of warm and could current is literally presented within this tank. Those who walks inside the tunnel can observe northern sea fishes to the right and southern sea fish to the left.
After coming out from the tunnel and viewing the entire tank, one can go into the exhibit of the northern sea. Sea Otters, Seals, and fishes from the sea of Okhotsk line up while you slope up to the Ocean Atrium on the fourth floor, where abundant sunlight fills the space.
Ocean Atrium is a grand space covered with glass blocks and large glazed opening on the wall. The height of walkway is set to the water level of the tanks so that 5 tanks showing 3 different part of ocean (northern, southern, and the border) becomes one in sight to represent the vast size of the ocean. To keep comfortable climate for life in each tank, the room temperature is diversified within the space. At northern sea area, the room is set to keep 5 degree in Celsius whereas in the southern sea area it is set to 30 degree Celsius (both for the sea mammals). Visitors would feel the climate change by one's own body. To exhibit this diverse seascape in one continuous space, no enclosure was provided inside this zone. State of the art technology such as ultra slow fan providing cold air, floor radiating heater, and air flow control along the wall, etc. has made this extremely diverse temperature in one space possible. It was intended to provide an opportunity to experience this co-existence of cold and warm atmosphere which is, just like the border seascape, one of the major character of Fukushima region.
Through the large window, the Abukuma mountains are in sight. This north faced large opening is designed not merely to provide the view of the mountains but also to avoid direct sunlight. The uniqueness of this space above the tanks are usually maintenance space, not for the visitors. To open such a service space into public lets people understand further about the system of aquarium.
Visitors follow the slope going down through mangroves and tropical fishes gathering around their roots, watching them through the water. After the coral sea zone, one can reach lower exhibition room where small tanks with tropical fishes are placed. Further down the slope on the second floor is the Ocean Environment Information Center where one can touch and feel real ocean life and collect information on ocean environmental issues. To exit the building from here, moving walk in the glass tube connects to the entrance hall above the reflecting pool providing a view of the real ocean.
This route planning, connecting floors with slopes and escalators, makes disabled access easy and friendly. No special elevator only for disabled in isolation is necessary. Disabled visitors can experience and enjoy exactly the same route with others.
Structural design for this complex is designed by Ove Arup and Associates. We jointly developed the space and structure.
The galleria design concept is a repeating T-shaped frames resembling fish bones. Halls and Seminar rooms facing the galleria is supported by double canti-levered steel frame structure enabling continuous large space if all the movable walls are removed to facilitate various events.
Outer shell of the aquarium is a concrete ellipsoid shell in 100mm thickness with no beams, creating smooth texture outside and grand space enveloped with round wall to enhance character of the architecture.
 |
 |
 |
