1,000 Boats To Push Flood Waters From Chao Phraya River

[Scott]

Several off-topic posts have been deleted.

[TAWP]

To speed up the river's flow, the boats' propellers were helping propel the water. A recent experiment in the Noi River in Ayutthaya showed the method helped accelerate the water flow by 20%.

The government has decided to use more boats and carry out the method when the tide is still low. Science and Technology Minister Plodprasop Suraswadi said the 30 boats have increased the flow rate by three times.

I wonder if this Science minister has ever heard of a double-blind test...

[MaxYakov]

Not even taking into account what it would do down-stream to embankments and houses in the risk-zone.

i would not like to be in a ground floor condo on the banks of the river when 1000 large boats all turn on their propellars ...............when 1 longtail river taxi boat drives down it creates a wave that hits and splashes off both banks

somebody didnt think this through ..............

Who could that be? I've looked at boat wakes on the Phraya with Google satellite maps lately and it appears to me that the large wakes are from the hulls and not the propellers. Probably the same for longtails or they wouldn't be propelling themselves efficiently. You do bring up a good point about positioning the large (one would think) velocity-increasing vessels.

Phraya Boat (Note the two hull wakes and the single propeller turbulance going straight back):

[MaxYakov]

To speed up the river's flow, the boats' propellers were helping propel the water. A recent experiment in the Noi River in Ayutthaya showed the method helped accelerate the water flow by 20%.

The government has decided to use more boats and carry out the method when the tide is still low. Science and Technology Minister Plodprasop Suraswadi said the 30 boats have increased the flow rate by three times.

I wonder if this Science minister has ever heard of a double-blind test...

Maybe he just has a different definition for it: Blind politicians and people. TiT :jap:

[ThaiCozy]

I think guys you are a bit cynic with Thai, fluid dynamics does say that a flow can be speed up : Navier-Stokes equations state that changes in momentum (force) of fluid particles depend only on the external pressure and internal viscous forces (similar to friction) acting on the fluid.

I think they can do it!

Edited October 9, 2011 by ThaiCozy

[GazR]

No, this is not the only thing that is planned. They are having a ceremony to ask for mercy from the Water Goddess!

Don’t forget the bear party they will have while thinking they actually effecting the flood

What's a "bear party" ? A beer party they have in NZ?

[GazR]

This is the land contour from north of Auttaya South to the bay. A flood control channel although expensive would protect all of the communities south of it's inlet if sized appropriately. The slope shows it would be a very simple construction project. It would not need to be a concrete structure. The first southern 75 km stretch would protect Bangkok and the rest of the northerly section would protect Auttaya. If they were serious about flood control they have to invest in more than the gasoline for motorboat taxis. The path of the channel could be adjusted to minimize impact on the public and as it would remain dry during the major portion of the year could be crossed in many places without bridges. The laminar flow would transport water very quickly from the north to the bay. The extreme northern inlet could be located close to Pa Mok and the inlet south could be located close to Ratchakham.

Utilizing a straight path as you show will be much more efficient flowing water than the meandering river, which normally would adjust itself if the banks didn't constrain it.

Since there is such a slight elevation change and tidal levels acting against the flow, planning for the 100, 300 or 500 year flood volume would make a bypass fairly wide.

Bangkok is in a precarious locale, like the delta of Bangladesh.

A new or full moon tidal flow will make more difference both positive and negative than putting boats on the river.

A flood control channel may or may not work, but would need something like the Thames barrier to avoid problems at strong flows, high tides, storms, any combination. Furthermore the waterfront left and right of the end of the channel would also need extra protection to avoid just moving problems. All doable, just a bit of planning, consistency, some money, political will to make difficult decisions, etc., etc.

The Dutch have some experience in this. Models calculating risks and change-of-flooding even put a price on a human life (2.2 million Euro, 2008 level).

http://en.wikipedia....iki/Delta_Works

From your local Dutch uncle

You forgot one thing - unlike Holland, life is cheap here (and I'm not talking about the cost of living).

[bigbamboo]

Maybe they could drain a big lake and divert all the water into that. Well, Plod started it!

[MaxYakov]

I think guys you are a bit cynic with Thai, fluid dynamics does say that a flow can be speed up : Navier-Stokes equations state that changes in momentum (force) of fluid particles depend only on the external pressure and internal viscous forces (similar to friction) acting on the fluid.

I think they can do it!

So ... you think the Thais are operating under the same physical laws and that they can actually use boat propellers to accelerate water? I'm think I'm detecting cavitation here.

[GazR]

This is the land contour from north of Auttaya South to the bay. A flood control channel although expensive would protect all of the communities south of it's inlet if sized appropriately. The slope shows it would be a very simple construction project. It would not need to be a concrete structure. The first southern 75 km stretch would protect Bangkok and the rest of the northerly section would protect Auttaya. If they were serious about flood control they have to invest in more than the gasoline for motorboat taxis. The path of the channel could be adjusted to minimize impact on the public and as it would remain dry during the major portion of the year could be crossed in many places without bridges. The laminar flow would transport water very quickly from the north to the bay. The extreme northern inlet could be located close to Pa Mok and the inlet south could be located close to Ratchakham.

So what would you say is the degree of difference between the laminar flow of the Chaophraya and the mooted flood control channel and how much difference would that actually make, do you reckon?

Meandering rivers have chaotic flow where flood channels should result in laminar flows. Big difference in how energy is expended and the overall speed of the volume of water. I have given you enough to go on to Google the differences for yourself as I can give you no specifics.

Yep that would help the flow considerably especially if they added REAL pumping stations.. It need not be concrete but should have rock banks to prevent erosion, I've noticed there are several rivers here in Bangkok that have natural banks and roads running next to them one in particular has a drainage klong on one side and a wide flowing river on the other and they are constantly rebuilding the roads and the river bank as the flowing river erodes the bank below water level.

The fact that the drainage klong is only a few meters from the flowing river adds even more erosion as the water is leeching underneath between the 2. After only a year or 2 of erosion the road begins to get that washboard effect again and the river banks are flattening out, using large rocks to support the river bank would economically curb this process and pay for itself with years of maintenance free service from the road and the river bank....

Depth, width and bottom inconsistency create resistance to flow of which all have extreme effects on the rate of a rivers flow.. Done right and they could even install low flow, electric generating turbines to make good use of the additional water flow in the season without adversely effecting the intended purpose of faster water evacuation.

I'll tell you something else, this would give those poor folks in the line of these floods far more to like the government for then tax refunds on new cars or tablet computers all of which may end up underwater the next rainy season..

But won't this wash away the island Thaksin promised to build in the gulf?

[GazR]

ummm...what about the left and right sides of the river?

Hope those soi dogs know how to surf....This really has to be the stupidest thing I've heard during the 15 years I've been in LOS.

You'd have to be travelling at the speed of sound for it to be effective.

Where's the moron smiley when you need it?

It surpasses the previous stupidest idea... which, coincidentally, was by the same man... so now he's got #1 and #2

Pheu Thai Party-list MP and former Chiang Mai Night Safari Project Director, Plodprasop Suraswadi

Chiang Mai Safari: Rare Animals On The Menu At Zoo, Eat lion, tiger, elephant, giraffe meat

CHIANG MAI: -- Visitors offered daily buffet of lion, tiger, elephant and giraffe meat; conservation groups outraged. Lovers of “wild” cuisine are in for a treat when Chiang Mai’s Night Safari opens next year, Project Director Plodprasop Suraswadi said yesterday. Visitors to the park’s Vareekunchorn restaurant will have the option of tucking in to an “Exotic Buffet” of tiger, lion, elephant and giraffe, for just Bt4,500 a head.

http://www.thaivisa....post__p__549707

Yet another clown from Thaksin Town: What IS it about Chieng Mai ??

[GazR]

How they can be so stupid.They just have to drill a deeeeep hole in the bottom of the river and all the water will flow into the south pacific ocean.

They already thought of that, but then they realized that when the aircraft carrier was sucked into the giant vortex it would plug the hole.

[rubl]

Meandering rivers have chaotic flow where flood channels should result in laminar flows. Big difference in how energy is expended and the overall speed of the volume of water. I have given you enough to go on to Google the differences for yourself as I can give you no specifics.

Yep that would help the flow considerably especially if they added REAL pumping stations.. It need not be concrete but should have rock banks to prevent erosion, I've noticed there are several rivers here in Bangkok that have natural banks and roads running next to them one in particular has a drainage klong on one side and a wide flowing river on the other and they are constantly rebuilding the roads and the river bank as the flowing river erodes the bank below water level.

The fact that the drainage klong is only a few meters from the flowing river adds even more erosion as the water is leeching underneath between the 2. After only a year or 2 of erosion the road begins to get that washboard effect again and the river banks are flattening out, using large rocks to support the river bank would economically curb this process and pay for itself with years of maintenance free service from the road and the river bank....

Depth, width and bottom inconsistency create resistance to flow of which all have extreme effects on the rate of a rivers flow.. Done right and they could even install low flow, electric generating turbines to make good use of the additional water flow in the season without adversely effecting the intended purpose of faster water evacuation.

I'll tell you something else, this would give those poor folks in the line of these floods far more to like the government for then tax refunds on new cars or tablet computers all of which may end up underwater the next rainy season..

But won't this wash away the island Thaksin promised to build in the gulf?

Stupid question, not build yet, meant for foreigners mostly anyway, so who cares. This apart from the fact that all should know that the Gulf and the Ocean behind are soo big, no one will notice the extra water

[GazR]

If they all reverse down the river.......nah forget it!

Best idea I've heard so far, actually.

[MaxYakov]

This is really sad. For the sake of Bangkok residents I hope the government isn't relying just on this plan to alleviate the flood waters....

Absolutely not! They're going to convert that abandoned highway/mass transit construction at and about Chaeng Wattana into a runoff aqueduct.They just have to work out how to get the water to that height.

[WarpSpeed]

I think guys you are a bit cynic with Thai, fluid dynamics does say that a flow can be speed up : Navier-Stokes equations state that changes in momentum (force) of fluid particles depend only on the external pressure and internal viscous forces (similar to friction) acting on the fluid.

I think they can do it!

There ya go!! The power of positive thinking!!

[GazR]

I'm surprised that our beloved politicians have not suggested pushing the moon away so that the high tide changes by a week, thereby allowing the water from the North to flow into the sea. It seems so obvious!

Come Come Now Foolish Farang - The Powers That Be Are On Best Terms With Rahu AKA The God Of Darkness So It Shall Be Done, Chop Chop !!

(BTW does Rahu get off on zebras or elephants or what? He's gonna need a lot of whatever it is!)

[GazR]

Meandering rivers have chaotic flow where flood channels should result in laminar flows. Big difference in how energy is expended and the overall speed of the volume of water. I have given you enough to go on to Google the differences for yourself as I can give you no specifics.

Yep that would help the flow considerably especially if they added REAL pumping stations.. It need not be concrete but should have rock banks to prevent erosion, I've noticed there are several rivers here in Bangkok that have natural banks and roads running next to them one in particular has a drainage klong on one side and a wide flowing river on the other and they are constantly rebuilding the roads and the river bank as the flowing river erodes the bank below water level.

The fact that the drainage klong is only a few meters from the flowing river adds even more erosion as the water is leeching underneath between the 2. After only a year or 2 of erosion the road begins to get that washboard effect again and the river banks are flattening out, using large rocks to support the river bank would economically curb this process and pay for itself with years of maintenance free service from the road and the river bank....

Depth, width and bottom inconsistency create resistance to flow of which all have extreme effects on the rate of a rivers flow.. Done right and they could even install low flow, electric generating turbines to make good use of the additional water flow in the season without adversely effecting the intended purpose of faster water evacuation.

I'll tell you something else, this would give those poor folks in the line of these floods far more to like the government for then tax refunds on new cars or tablet computers all of which may end up underwater the next rainy season..

But won't this wash away the island Thaksin promised to build in the gulf?

Stupid question, not build yet, meant for foreigners mostly anyway, so who cares. This apart from the fact that all should know that the Gulf and the Ocean behind are soo big, no one will notice the extra water

Thanks again for pointing out the bleeding obvious i.e. that you have no sense of humor.

[letitbe]

he must be part of new government since its hard to believe anyone can believe this total nonsense but sort of idea we can expect from Taksins sheep Talk about laughing stock

[phetaroi]

Wow they're actually going ahead with this sadly embarrassing folly then.

Thailand gets an enema!

[OzMick]

May I introduce a concept - water gradient.

Part of my former occupation was pumping fairly large volumes of water from a 3km (more or less) canal with a dam at one end and pumps at the other. Before starting the water in the canal would be level. After the 1st pump was started there was an observable drop at the pump end, and as water was released from the dam (increasing the level at that end) and more pumps started, this level difference would increase peaking at around 1m at maximum flow. The height differential was the cause of the water moving - it was running downhill in a level canal.

Form a line of boats across a river. If the impulse from the propellers on the stationary boats is going to increase the flow of the river, there should be an observable decrease in the river level before the propellers (to increase the water gradient and hence flow rate TO the propellers) and an observable increase in height after the propellers (to increase the flow rate AWAY). If you like, a standing wave.

Also consider the huge amount of kinetic energy of millions of tons of water currently flowing in the Chao Phraya. The formula for kinetic energy is

e= 0.5 x mv² If you want to double the speed of the flow, you would need to add 3 times the energy the water currently possesses. Good luck with that.

IMHO boat propellers will give a localised increase of flow rate, which will be dissipated as friction with slower water molecules. What this will do is heat the water so marginally as to be unobservable.

Edited October 9, 2011 by OzMick

[daiwill60]

The series of shots shows the construction of LA's flood control channel, it's finished operation during non flood periods, and fully functioning during flood conditions. The bottom shot show a channel which is not lined with concrete.

The top shot is the original LA River, which was paved over (very early shot, notice the old car on the right). It would have been better to allow some leakage back into the ground along the way, like the bottom picture which is the San Gabriel river. Both have dams at the base of the mountains which act as part time flood collectors and most time recreational areas. Even Sepulveda Dam (seen in many commercials and TV shows) is a flood control (usually) dry dam.

In the old times in areas like Thailand or Egypt, flooding was good for the fields as new rich silt was deposited to make farming better. Now with the control of the rivers, more silt goes out to sea, in Egypt the Aswan dam collects the silt, probably making the situation worse by raising the seabed, reducing the flow, like what happens in the US by New Orleans.

River management and flood mitigation are expensive and often have unintended consequences. Building for the eventual Maximum flood is more expensive, and usually not approved due to costs. And large projects often, regardless of where you live, are breeding grounds of corruption.

River bypasses are used commonly throughout the world. A small example can be seen below. This particular bypass is in Bad Oeynhausen in Germany. They can be quite benign and are simply used to provide a short clean path for flood waters.

I would liken the construction of such a flood bypass for Bangkok as similar in scope to the building of a major roadway.

Your comments on graft and corruption are indeed true but it appears that you advocate no solution is the best solution?

Perhaps they should move Bangkok to the Khorat Plateau?

Apparently that already seems to be happening, as more and more Thais from Bangkok are buying up and building on land all over the place up here in areas like Khon Kaen, Mahasarakham, RoiEt etc maybe they know something others do not. Maybe Mr Dropaplop ( because he really has with this idea ) is one of them.

In fact my missus keeps showing me some internet map image projection of Thailand in about 10 years i think its , where Thailand is all but cut in half from Bangkok to Khorat plateau by water level increases caused by global warming ( sorry ) Climate Change, as it now known.

Edited October 9, 2011 by daiwill60

[atyclb]

May I introduce a concept - water gradient.

Part of my former occupation was pumping fairly large volumes of water from a 3km (more or less) canal with a dam at one end and pumps at the other. Before starting the water in the canal would be level. After the 1st pump was started there was an observable drop at the pump end, and as water was released from the dam (increasing the level at that end) and more pumps started, this level difference would increase peaking at around 1m at maximum flow. The height differential was the cause of the water moving - it was running downhill in a level canal.

Form a line of boats across a river. If the impulse from the propellers on the stationary boats is going to increase the flow of the river, there should be an observable decrease in the river level before the propellers (to increase the water gradient and hence flow rate TO the propellers) and an observable increase in height after the propellers (to increase the flow rate AWAY). If you like, a standing wave.

Also consider the huge amount of kinetic energy of millions of tons of water currently flowing in the Chao Phraya. The formula for kinetic energy is

e= 0.5 x mv² If you want to double the speed of the flow, you would need to add 3 times the energy the water currently possesses. Good luck with that.

IMHO boat propellers will give a localised increase of flow rate, which will be dissipated as friction with slower water molecules. What this will do is heat the water so marginally as to be unobservable.

Interesting engineering perspective.

What if they were to dredge the rivers? would that not increase the flow volume?

[rubl]

IMHO boat propellers will give a localised increase of flow rate, which will be dissipated as friction with slower water molecules. What this will do is heat the water so marginally as to be unobservable.

So what you are saying is that the Science Minister Plodprasop is at least partially right. Looking at the OP that would be "water three times faster". Just skip any on 'drain' and 'prevent floodwater pouring into Bangkok'

Edited October 9, 2011 by rubl

[ryladie99]

This is really sad. For the sake of Bangkok residents I hope the government isn't relying just on this plan to alleviate the flood waters....

Thanks for posting.. and I agree with you 100% .I would urge the Farangs in Thailand to help donating money to he or she's Red Cross...so we can help the Thai...any amount will do you all can send to the Red Cross in your country...and make sure where the money goes..

I myself will do the same...I am going to donate to the flood in the Philippine as well as Thailand...

Any amount will make a difference...time to help people who are suffering and some lost everything...

Thank you and I appreciate everyone who read my post..

Grateful...

[canuckamuck]

You can't push water past an area without increasing flooding when a river is already flooding. If they were able to move the water faster they would simply increase the height of the flood crest. Is this not the opposite result they are hoping for?

Dams work because they they slow the flood not speed it up.

[DavidHouston]

To speed up the river's flow, the boats' propellers were helping propel the water. A recent experiment in the Noi River in Ayutthaya showed the method helped accelerate the water flow by 20%.

The government has decided to use more boats and carry out the method when the tide is still low. Science and Technology Minister Plodprasop Suraswadi said the 30 boats have increased the flow rate by three times.

I wonder if this Science minister has ever heard of a double-blind test...

Maybe he just has a different definition for it: Blind politicians and people. TiT :jap:

Thank you for that thoughtful reply. Question. If a boat is floating in a river; the boat is pointed directly upstream, and the engine in the boat is running at a speed at which it is neither moving downstream nor powering upstream, will the propeller be moving water downstream faster than the current, or is the power merely sufficient to keep the boat from being pushed downstream?

Alternatively, if the boat is tied to a tree or a bridge, and therefore the engine is not being used to propel the boat forward or to keep the boat from moving downstream, then is the motive power of the engine being used to force water faster downstream? (An inherent assumption is that friction of the water against the hull of the boat and the inefficiencies of the motor and propeller (e.g. cavitation) are not being taken into account.)

What do you think? Is there a difference in the utility between a tethered and un-tethered boat?

[MaxYakov]

May I introduce a concept - water gradient.

Part of my former occupation was pumping fairly large volumes of water from a 3km (more or less) canal with a dam at one end and pumps at the other. Before starting the water in the canal would be level. After the 1st pump was started there was an observable drop at the pump end, and as water was released from the dam (increasing the level at that end) and more pumps started, this level difference would increase peaking at around 1m at maximum flow. The height differential was the cause of the water moving - it was running downhill in a level canal.

Form a line of boats across a river. If the impulse from the propellers on the stationary boats is going to increase the flow of the river, there should be an observable decrease in the river level before the propellers (to increase the water gradient and hence flow rate TO the propellers) and an observable increase in height after the propellers (to increase the flow rate AWAY). If you like, a standing wave.

Also consider the huge amount of kinetic energy of millions of tons of water currently flowing in the Chao Phraya. The formula for kinetic energy is

e= 0.5 x mv² If you want to double the speed of the flow, you would need to add 3 times the energy the water currently possesses. Good luck with that.

IMHO boat propellers will give a localised increase of flow rate, which will be dissipated as friction with slower water molecules. What this will do is heat the water so marginally as to be unobservable.

Best post I've seen on this, IMHO. It looks to me like it's also localised in another way in that the amount of water accelerated is a small percentage of total river flow even with a large number of boats. Unless they use some very big boats with very big propellers (or maybe I'm simply restating in another way the relatively large amount of energy that would be required).

Plus, it seems to me also that since the boats are tied up at shore, part of the accelerated water is reacting with the shore's boundary layer which has much less velocity, increasing the friction and rate of deceleration of the water.

This does not seem to jibe with the Minister of Science and Technology's claim of fairly dramatically increased flow rate using a smaller number of boats (Sept. 22nd Bangkok Post article). Makes me wonder how and where the measurements were being made.

I have a tendency to not go with the flow regarding his measurements. (Sorry. Couldn't resist.)

Edited October 9, 2011 by MaxYakov

[Thai at Heart]

Everyone should go to the mouth of the river and the beach in the Gulf of Thailand and take one bucket of water out to make space for the oncoming flood.

Obviously this is in jest, but who knows, maybe the science minister has a brother with a bucket factory.

[Colin Yai]

An anagram of Plodprasop is Sad Plop Pro.

Yeah the face that launched a thousand boats