Saturday, December 31, 2011

20120101 Fundamental Resolutions to Singapore Floods

Referring to so frequently repeating flood 20111223 Orchard Road Flood Again - Media Report & PUB Findings

Singapore frequent floods can be fundamentally resolved.

Our flood is due to downstreams ponding, not due to
1. Immense water cathment upstreams, like Kuala Lumpur (Conventive Effect from Immense cathment Upstreams) , better
2. No intensification by Orograhpic effect in Thailand (Orographic effect from immense cloud up North blocked by Northern mountains tapering off Mount Everest)

PUB using the right word, "Ponding."
Ponding means water stayed stagnated as a pond, not flowing.
Therefore the solution is quite clearly implied, we must make the water flow, we must therefore break this stagnation.

There are two level of "Ponding"
Micro-scopic - Choked filter, drains.
When there are too many filters, drains than necessary, they are too costly, if not impossible to clean frequent enough. The retired Chief Engineer of Munciple New Delhi educated me  " Covering of drains has many operation hazards. Regular inspection & maintainenance become difficult"

Macro-scopic -
1. Excessive deep drains upstreams, resulting in no gradient even at mid streams Gradient is the fundamental requirement for water to flow. "人往高出,水向低流" (following blogs provide more details).
2. High water level down streams, easily adjusted by barraged Marina Bay (Marina Bay water is not yet ready for treatment for drinking, therefore there is incentive to expedite the discharge of water. But how to discharge the saltier and keep the fresher one, easy solutions will be provided. Inventor learnt from EDB founders on how they face the challenge when they barrage up Jurong River, where fresh water flow away from the top, while saltier are retained at the bottom, he did not find easy solutions then.)

Raising orchard road will they break this stangation?
A one month ahead warning was given on 20110505 prior to 20110605 floods.
The potential impact were then listed including leakage to basement and underground infrastructure, MRT included.
20110505 Multi-billion Dysfunctional Waterway - Reasons & Solutions

Therefore proposed new barriers, revising building codes will they solve the problem?

In Engineering, there is no perfect solution, as we can always improve on even the best solutions, even assuming situation does not change.

However, there are
1. Costly Solutions - cover the drains, adding construction, maintenance cost.
2. Ineffective solutions - enlarge drains without increasing gradient
3. Worsening solutions - deepen drains by sacrificing gradient, therefore slow flow down, silting and choking of drains resulting. 
4. Complicating solutions - raising road level that move flood upstreams.

Solutions have been prescriebed below and i thank Dr Vivian for he has keep this inventor encouraged that he has held discussion with PUB leaders, on the importance of speedying up the flow.

Speedying up flow, compare to the year long raising orchard road and building motorized barriers, 
1. The most expedient, as it address the root cause
2. Least costly (land, labor and construction upfront, inspection and maintenance in future).

It must be done, even Bukit Timah, Newton, Kampong Java can be resolved. This is after studying 1880 Singapore maps.

Immediately the solution, is to lower the Marina Bay water level to lower than the ten years lowest tide.
So that we have enough time to activate the pumps, if the heavy storm sustain longer than half hours.

May i clearly stated:
1. Installing sensors
2. Modeling water flow without speeding the flow
3. Raising road level like Orchard Road
4. Building barriers like Wheellock place

No matter how much, how fast, how high tech they are, they are irrelevant.
Irrelevant solutions are not changing the root cause of the problem - water stagnation, succintly as PUB put it "Water Ponding"

20110920 SASC1 -  Waterway Design for Global Warming 

20110920 SASC2 Singapore Unique Advantage
20110920 SASC3 What Impede Flow - Over-sized Excessive Depth 

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