Causes & Types
What are overflows of large amounts of water?
Floods
New Orleans is vulnerable to flooding because much of the land has sunk and at it is easy for coastal floods to enter the sunken city. Why is is vulnerable?
It is below sea level (height above sea level)
What type of effect is loss of life?
Social
Which river, due to its location and size, was the focus of our case study in Jakarta?
Ciliwung
If you deepen or widen a river and repair its banks, what are you doing?
Channel improvements
Which flood is dangerous because it can happen anywhere and anytime, often with no warning.
Flash Flood
Shanghai is ripping up concrete and creating new "green" areas. How are they becoming less vulnerable?
Increasing permeability of the ground so water will be absorbed instead of pooling.
What type of effect is damage to machinery and equipment?
economic
Why is Jakarta sinking?
1. Reliance of pumped water over piped water (due to neglect during colonial periods)
If you prevent anyone from living within 50 meters or a river (should be much further), what are you doing to prevent destruction?
What are the main causes of river floods (there are 2)
1. Rainfall
2. Snowmelt
Seoul's Han River often floods even though the river has been expanded and "normalized". Why is the city vulnerable to floods.
Seoul has close proximity to water, rivers naturally flood.
Which social impact is caused by widespread destruction or lack of access of homes?
Homelessness
What is controversial about the river "normalization" projects?
Eviction of residents
If you require residents to build homes an businesses on a higher elevation above the river, what are you doing?
minimum platform requirements
Failure of these can worsen floods or even cause them.
Man-man structures: dams, levees, dikes, floodwalls
Houston often floods because drainage canals haven't been completed due in part to rapid population growth and development. What should the city focus on?
channel capacity
Why might you not want to be drinking water after a flood?
contamination from sewage or chemicals
Why will a sea wall built around the north end of the city fail?
The city is sinking, the wall will sink as well. The sinking must stop first
What would be a solution to impermeable ground cover?
pervious asphalt/concrete, adding: rain gardens, trees, grass, green/garden roofed house/apartment, restoring wetlands, overall more green spaces.
What are the three main causes of coastal flood (aside from floodwall failure)
1. storm surge
2. tsunami
3. high tide
Identify all ways in which Jakarta is vulnerable to floods.
1. below sea level
2. proximity to several bodies of water
3. impermeable ground cover
4. poor channel capacity
You may die after a flood has occurred if emergency services can't get to you. What is the most likely reason they will not be able to access you?
damage to transport infrastructure
What is the shape of the original giant seawall intended to protect Jakarta? (abandoned now due to ecological, economic, and political factors)
Garuda
What would be a solution to coastal flooding?
Flood walls, storm water inlets, oyster beds, mangrove forests, stilt houses, or barrier islands