River Division

Last Update: Mar. 21, 2008

Basic Hydraulic Experimental Facilities

: 2-Dimensional Flow Channel

　There are channels of various sizes with various accessories, which are needed for proposing and revising hydraulic design methods of river structures, studying habitats of river organisms, etc.

Diffusion Channel
2-Dimensional Flow Channel
Sediment Transport Channel
Inclination-variable Sediment Cycle Channel
Structure Channel
Meandering Channel

Large Scale Experimental Channel

: High Drop Channel

　Studies that need full-scale experiments are conducted using the following three large channel models, which are largest in Japan.

Large Scale Channel
High Drop Channel
High-speed Flow Channel

Outdoor Model Experiment Facilities

: Shigenobu River Model

　Reduced sized models of sections of rivers are constructed to experimentally investigate channel designs and problems related to the designs of river structures, such as weirs and revetment. Reduced sized models of sections of rivers are constructed to experimentally investigate channel designs and problems related to the designs of river structures, such as weirs and revetment.

Shigenobu River Model
Tama River Model

Indoor Model Experimental Facilities

: Kariyata River Model

　Small ripples produced by wind on the surface of a model are huge waves of several meters when converted into an actual size, and thus phenomena shown in a model may differ from those in actual rivers. This 50-m wide and 200-m long facility is roofed to minimize the effects of wind. It is used for model experiments that need particularly precise water level measurements and for studying diverging points and river mouths.

Hii River Model
Kariyata River Model

Water Quality Analytical Lab.

: Water Quality Analytical Lab.

　Rivers transport sediments, nutrients and toxic substances from land and flood plains together with water collected from the basin. The water quality analytical laboratory is equipped with various kinds of analytical instruments and refrigerators and analyzes substances contained in turbid water collected from several target rivers in Japan during floods.

Hinuma River Flood Observatory

: Hinuma River Flood Observatory

　The observatory is located at 28.1 km point on the Hinuma River of the Naka River System. It consists of a 30-m span support constructed across the low-flow channel, a 15-m span elevating stage on the support, and an inspection bridge. The elevating stage is on the low-flow channel and moves vertically within a range of 6 m to facilitate flowing water to be observed from a short distance even during a flood.