Flood disaster management practices and vulnerability in Japan, the Netherlands and elsewhere.
Friday, December 30, 2016
Final post
A new job in the field of energy based on nano-materials is taking me back to the core of environmental sciences, but sadly outside the field of water related hazards (for the most part). That is why this will be the final post in this blog for the time being. Let's do our best to prepare for the days yet to come!
Friday, December 23, 2016
News in Japan - December
USA
Netherlands
Dutch coast ‘superstorm’ proof for the next 50 years The embankments that protect the marina have been topped with Xblocs to break high waves. Xbloc is an innovative concrete armour unit which has been developed by Dutch contractor BAM - under its trade name Delta Marine Consultants - for shore protection and breakwaters. Xblocs have a high hydraulic stability and requires considerably less concrete compared to other armouring systems and furthermore the units can be placed faster. This is the first time Xblocs have been used along the Dutch coast.
PhD-student experimented with 10.000 plastic river plants in waterlab, the Netherlands In the main channel of the waterlab at Delft University of Technology in the Netherlands, PhD-student Andrés Vargas-Luna simulated the shaping of rivers including the effects of vegetation. He did this by putting 10.000 small plastic plants in the channel. "Problems arise when trying to calculate their extension as there are no models for this. It is often assumed that the land that erodes from one bank, expands the other. I want to know which role vegetation plays in the development of riverbanks.” The outcomes of his research emphasize the relevance of considering the effects of vegetation on the river management and on the designing, planning and maintaining of restoration projects.
Other
Most UK coastal flooding caused by moderate, not extreme storms The researchers also identified four main storm track pathways approaching the UK (mainly from the westerly and northerly directions) and four broad corresponding footprints of extreme sea level events (four sections, which together, make up most of Britain's mainland coastline). Clustering of storms, such as happened during the 2013 -- 14, or even 2015 -- 16 season, is an important issue. It can lead to large socioeconomic impacts and cumulative insurance losses. Before now, knowledge of this area has been limited, but our study will help better inform flood management, the insurance sector, and national emergency and infrastructure resilience planning to minimise the impact of successive storm events. The team has also developed a new database of coastal flooding for the UK called 'SurgeWatch' (http://www.surgewatch.org) which contains records, including photographs, of coastal flooding events over the last 100 years.
Thursday, December 1, 2016
Joso flood - ICHARM publication
My colleagues have just published an article in the Journal of Disaster Research, titled "The 2015 Flood Impact due to the Overflow and Dike Breach of Kinu River in Joso City, Japan" (doi: 10.20965/jdr.2016.p1112). You can access the full article for free by registering on the website for free as a member. This article discusses not only the geographic features making the area prone to flooding, but also the lead time to evacuation per district.
Abstract:
Heavy rainfall in September 2015 inundated the Kinu River basin and caused an overflow and dike breach of the river in the eastern part of Joso City, Ibaraki Prefecture, Japan. The area, which is bounded by the Kinu and Kokai Rivers, experienced deep inundation of more than 2.5 m, which continued for more than 3 days at the maximum level. Although the estimated maximum inundation depth and duration were basically related to the elevation and distribution of topographic surfaces, strong flood flow washed buildings away near the overflow and dike breach sites and caused deep inundation even though these sites were located on a relatively higher natural levee. In addition, serious damages such as interruption of emergency transportation routes and deep inundation over floor level occurred, isolating evacuation centers and important facilities including a municipal hall and hospitals. Few residents utilized the pre-prepared flood hazard map or understood the local geography, and evacuation orders were not fully transmitted to the local residents, which might have increased the flood’s impact.
Abstract:
Heavy rainfall in September 2015 inundated the Kinu River basin and caused an overflow and dike breach of the river in the eastern part of Joso City, Ibaraki Prefecture, Japan. The area, which is bounded by the Kinu and Kokai Rivers, experienced deep inundation of more than 2.5 m, which continued for more than 3 days at the maximum level. Although the estimated maximum inundation depth and duration were basically related to the elevation and distribution of topographic surfaces, strong flood flow washed buildings away near the overflow and dike breach sites and caused deep inundation even though these sites were located on a relatively higher natural levee. In addition, serious damages such as interruption of emergency transportation routes and deep inundation over floor level occurred, isolating evacuation centers and important facilities including a municipal hall and hospitals. Few residents utilized the pre-prepared flood hazard map or understood the local geography, and evacuation orders were not fully transmitted to the local residents, which might have increased the flood’s impact.