Field Trip to Tone weir and ADCP

Despite the cloudy weather, we had a very educational day outside at a Tone river weir and doing some Acoustic Doppler Current Profile experiments.

This weir in the Tone river is near Gyoda city, in Saitama prefecture. It divides part of the water from the Tone river in 3 new river sections, flowing to different areas for drinking water and irrigation. This water is brought to the majority of Tokyo city! The weir also features the most nature friendly fish ladder I have seen so far. What's more, it shows actual proof of success: you can go downstairs next to the fish ladder and look at the jumping fish through a series of windows. They jump so fast, it wasn't possible to catch one on photo, but we saw small fish like sardines and a white fish of about 30 cm long. The MLIT office itself was retrofitted but still showed cracks from an earthquake (or more).

In the afternoon we met an ICHARM researcher at the Taisho Bridge on the Tone river and learned about the ADCP technique. This floating measurement device costs more than a Ferrari, we were told. During an actual flood it must be far more difficult to perform these measurements. The best part of the rainy day was that the bus driver provided us all with umbrellas.