Monday, June 4, 2012

Field Trip to Kokai river drills

Last month while mount Tsukuba reflected in the watered rice paddies, we ventured to a private flood fighting drill at Kokai river's Asahigaoka town.

Asahigaoka was a rural area in great danger of flooding. As an example to other areas, all the residents were united in the plan to relocate the houses and industries to a concentrated elevated area, and redistribute the remaining land as low lying farm land. Two notable exceptions were a large industrial factory, and a cemetery, both still in the same location albeit on elevated land. The farm land doubles as a retarding basin, and one of the levees at the East side doubles as an overflow levee during high water. Today it was not flooded with water, but rather with firetrucks, as all the local flood fighting teams (suibo), which often double as fire fighters, came to practice their mandatory drills with much enthusiasm and military preciseness.





Much like the Tone river drill, though on a somewhat smaller scale and without helicopters saving people from rafts in the river, the individual groups reported their presences and eagerness to fight the simulated floods. The different types of simulated floods, overtopping, seepage and levee breach, as well as the methods to counteract them (many using bamboo), were much the same as during the Tone river drill. This time however, we got to stand right in the action zone and even got to lift a 20 kg sandbag. Most important was how to practice the knots tied to trees to slow down water.







We conducted interviews with several members of the flood fighting teams. As soon as the final drills were reported complete, everyone packed up and within 5 minutes the fields were clear as if there had never been anyone there. The seriousness and collaboration of the whole morning was very impressive, as many of these people are volunteers.




Sunday, June 3, 2012

Trip to Katori

Today we visited Katori city in Chiba prefecture, and some public water works on the way. 

The day started out rather drizzly, but the weir near Kasumigaura was fascinating nonetheless. We could smell the salt ocean winds blowing across the water, as we were only 5 km from the coast. At one of the 8 prefectural history museums, all the different types of concrete seawall or river levee blocks were displayed. Which shape is your favorite? They each have their own pros and cons: cost of material and difficulty to make, effectiveness of shape in relation to displacement, and fitting together with other shapes, be it similar or not. 













Once inside, it was allowed to take some pictures, except in the most interesting room displaying how rice agriculture was practiced in the last 100 years. There were flat bottomed transportation boats, manual wooden pumping mechanisms, and pictures of children left in floating tubs while the people worked in the fields. It even featured a graph of the necessary water levels in the paddies during rice growth. There was a map displaying historic floods in the Tone river area.


Across the road of the museum is a famous iris garden, where we were just in time to catch a wedding. The bride was floating through the water, surrounded by flowers and random onlookers, wearing a beautiful kimono. The park also features one of the wooden water mills used to irrigate the paddy fields. 
On the way to Sawara, the part of Katori city we were interested in visiting, we stumbled upon another lock gate. Influence from English engineers at the time are still clearly visible.




Sawara town has a lovely canal area with Edo period buildings, and a museum dedicated to one of the first cartographers of Japan, Ino Tadataka. After finishing his career, he started to travel around Japan and measure the coastline precisely using state of the art techniques of that time (around 1800). It took various expeditions to cover entire Japan, and his maps were remarkably accurate and also included an island that is now part of Russia. The very maps he created during his travels are displayed in the museum. Given the displacement following major earthquakes both in the horizontal and vertical direction (the last Tohoku disaster caused 1.2 meter downward and over 5 meter Westward displacement), it would be more fair to compare his maps to the geographical situation at the time, but of course his maps were the most accurate work of that time. The local shops have an incredible amount of crafts, as well as the visitor information center which is located in a former bank.






Friday, June 1, 2012

BSc student final presentation

Today was the final presentation of Babeth Bosma, visiting internship student from the Dutch University of Wageningen, Water Resource Management Group & Disaster Studies, Social Sciences Group. 

Babeth presented her findings from visiting and interviewing various local groups involved in flood management, such as the volunteer flood fighting teams. The topic of her bachelor thesis is titled 'Local Coping with a National and Worldwide Problem, Flood Risk Management in an Ageing Society: The Power of the Elderly. Case Study: Kokai River Basin, Ibaraki Prefecture, Japan'. I have thoroughly enjoyed being her co-supervisor on this challenging topic.