Flood In Penang
Copied from IEM members group.
1. Why do floods happen in Penang?
Very simple. The rivers and streams cannot contain the large volume of surface runoff generated by the rain. Every river and stream has a certain capacity – once the capacity is exceed, floods happen.
2. Why do floods happen in KL, Selangor, Kelantan, Pahang and all other places?
For the same reason.
3. Does development makes the flood worse?
Yes. The more concrete you have, the less chance for the water to seep into the ground and hence more water flows as surface runoff.
4. Are developers the main culprit?
Not necessarily. A lot of things contribute to the worsening of the floods, including you and I. When we pave our lawn with tiles instead of planting grass, we increase surface runoff. When we build roads, we increase surface runoff. When we build shopping malls, we increase surface runoff. People also make floods worse by throwing rubbish and clogging up drains and streams.
5. Are development in the hillslopes such as that in Penang bad for floods?
Yes. Because of the steep slopes, the surface runoff is generated at a higher pace and will aggravate floods more.
6. Should we stop all development and live in caves?
7. Did it flood because of Oktoberfest?
How did you escape from the mental hospital?
8. What other factors worsen floods?
High rainfall coinciding with high tides can make floods worse. Movement of rain clouds in certain direction can make floods worse. Wrongly designed structures like bridges or culverts can aggravate floods.
9. What can we do to minimise floods?
Control surface runoff at source. All development projects should have their own retention ponds. There should be retention ponds at strategic locations. Minimise areas that are paved – don’t try to concretise everything. Minimise development in hillslopes. There are new materials that are porous that can be used for roads and pavement. The guidelines by Dept of Irrigation and Drainage has many measures to contain surface runoff and minimise floods – adopt some of them.
10. Is it easily done?
11. Is depening and widening the rivers a good solution?
No. Deepening and widening rivers cause many other problems including the destruction of the river ecosystems. You only do it if you are desperate. Controlling surface runoff at source is the best way forward.
12. Can we prevent floods 100%