The Sotobori of Edo Castle served as three kinds of infrastructures, City defense, Environment (water and wind tunnel), and Logistics.
Even now, when you live on the Sotobori River on the boat, you can feel the temperature on it is a few degrees cooler than the temperature on the ground.
As Tokyo metropolitan Expressway will be partially transferred undergrounded after the 2020 Olympics, the primary issue for Tokyo should be recovering urban environment.
For that purpose, we proposed a reforming project of the riversides of Sotobori, which last for 2km long, as an environmental infrastructure.
The core conception of the project is to redesign the water of Sotobori itself.
It is not well known that the riverbed of the Sotobori is soil since the Edo period instead of concrete.
The project begins with the plan to use the small dredger, which can approach to Sotobori from the Tokyo port with the present water level of Sotobori, to clean the riverbed which has been covered with sludge by the daily life drainage.
So we will create a new ship route in Sotobori which is accessible for a larger boat.
As a consequence, the small tourist boat departing from the Sumida River from Asakusa and Skytree will be able to reach the Nihonbashi through this route via the transfer pier of the Hama-rikyu.
At the same time, small reclamation will be carried out at the riverside with higher land price by making use of the soil generated by the dredging, in this way, it is possible for the project to meet the economic demand as a redevelopment project.
The newly drawn outline of the Sotobori also serves as a revetment line being accessible for small wooden boats to access the wooden commercial facilities such as hotels, shops, and restaurants, on the riverside.