The concept is of a waterfront that is developed by excavating the soil in a low ground area down to a few meters below the surface and then flooding the area to construct an artificial reservoir. The foundations for an urban community float in the artificial reservoir, and buildings and other facilities are constructed on these floating foundation. Thus safe comfortable social infrastructures can be constructed in urban "zero-meter" areas. They will withstand flood disasters and will never submerge even if the sea level rises. An added benefit is that the floating structures will have an excellent seismic resistance.

An outline of the process follows:

Step 1 An area equivalent to approximately half of the total area of the site is excavated up to a depth of several meters. The topsoil removed from the site is relocated in order to raise the urban site above sea level (See Fig. 1① and Fig. 1②).

Step 2 Concrete levees prevent erosion or destruction of the bank. The area inside the levees is then flooded until the water level inside the levees reached that of surrounding sea and/or river, to construct a man-made inlet and/or basin.

Step 3 Floating foundations constructed at shipbuilding facilities are towed to their sites. In principle, as is shown in Fig. 1③, the floating foundation keeps itself afloat but the proposal calls for what is known as the "Soft-Landing System." In this system, the floating foundations are semi-supported by piles constructed underneath.

Step 4 Finally, buildings are constructed on the floating foundations inside the man-made waterfront. Roads and bridges are constructed to allow passage between the floating foundations and the land as well as a water gate (See Fig.2).

Soft-landed water city can be developed using step-by-step procedures that befit the needs of the existing city, site conditions, construction period and so on. At the same time, the overall shape and size of the soft-landed water city vary according to changeable also at even the same site in consideration of future needs, the site condition of lower-lying land areas, population and so forth. Fig. 3 shows the schematic diagram for the water city in various stages. Fig.3① shows the initial stage of the water city where various housings are located independently. Fig.3② and Fig.3③ show the next stage where the public waterfront area including a canal for waterborne transportation has been developed. Fig.3④ indicates the final developed stage with usage of the very large floating structure such as "Mega-float".