“Eco-tank” is a system in which underground pre-cast (PC) water storage tanks comprehensively support flood control measures whilst protecting urban environments and people’s lives from flood damage.
- With spans of either 5 or 10m coupled with 2 types of beams that are assembled both vertically and horizontally, various sizes are possible.
- In comparison to conventional types, because the number of columns has been reduced, (a) the water inhibition rate at the columns and walls is lessened, (b) the water storage level is greater than tanks of comparable size, and (c) the depth of the tanks is lower than those of comparable surface area.
- In an effort to store the same water volume, due to the reduced level of columns, the requisite excavation volume is decreased leading to lowering of total costs.
- Because the spacing between columns is comparatively wide, cleaning vehicles are able to move throughout the system more freely.
- Because the main members are created in pre-cast concrete and pin-type structures are used to join members together, such as those within the roof structure, reduction of the overall construction duration is realised.
- As tensioning work between the assembled pre-cast concrete beams and slabs is not required, construction becomes simplified.
The “Eco-tank” can be installed underneath various types of public spaces such as school playing fields, parks, baseball grounds, tennis courts, and parking lots (installation underneath commercial facilities is also possible). Because the “Eco-tank” system utilises pre-stressed long-span structures whilst possessing few total members, the construction works are completed in an exceptionally quick manner making it suitable for adoption underneath areas such as school playing fields, which are generally constructed within a short time frame.
Water storage tanks are established underneath the flood control basin, which is situated directly adjacent to the river. By effectively integrating the flood control basin with the water storage tanks, improvements can be realised in the handling of increased water storage volume and the efficient usage of the existing land.
Overflow water from the river is initially trapped within the underground water storage tanks; however, as the overflow water levels rise, the rainwater is effectively captured by the flood control basin.
The flood control basin area is typically employed for multi-purpose usage such as for parks and playing fields in which the city residents can enjoy at their leisure.
The underground water storage tanks within the “Eco-tank” system are designed to effectively handle the relative frequency of flood damage over many years.
This method will combat the rare occurrence of major scale flood damage by employing an open reservoir which can catch possible water overflow. By decreasing the size of the underground water storage tanks whilst simultaneously efficiently using the available space directly situated above, initial investment costs can be minimised. Kawada is able to provide a system, recognised for its cost performance, in which the underground water storage tank’s operation and maintenance costs are kept at a minimum level.
