Supply Welsh water to south east England, says GMB union

[mark99]

3rd runway - lots of displaced homes. On that basis we assume those who object such things will refuse to fly Heathrow?

[Murflynn]

Never mind who 'owns' the water, w.t.f. is a trade union doing proposing major infrastructure projects?  Why don't they do what they were constituted to do?  If we are not careful they will become a non-parliamentary force like, for instance, the teamsters' union in America. ...........  god forbid.

[Bee]

36 minutes ago, Murflynn said:

 they will become a non-parliamentary force like, for instance, the teamsters' union in America. ...........  god forbid.

Or the religious right ........ God forbid (eh?!)

[Pluto]

On 09/06/2018 at 17:44, StephenA said:

Depends on how much water you want to pump through - the LLangollen carries quite a volume per day (12 million gallons) and that's narrow....

As Londoners use 600 million gallons per day, that amounts to a 2% increase, so hardly significant. It would allow every Londoner to flush the toilet every other day. As I suggested, to move significant amounts of water in a canal would make that canal virtually unnavigable.

[furnessvale]

4 hours ago, Pluto said:

As Londoners use 600 million gallons per day, that amounts to a 2% increase, so hardly significant. It would allow every Londoner to flush the toilet every other day. As I suggested, to move significant amounts of water in a canal would make that canal virtually unnavigable.

My calculations are probably wrong, but they come out as a flow of 1.4mph to put 100m gallons of water down an average narrow canal in 24hrs.  Obviously, bridge holes etc would speed the flow and some measures such as piston relief tubes could be required.

 

I will now recheck my figures and will probably come back to say what spherical objects I am talking! ?

 

George

[Pluto]

A narrow canal bridge hole is around 7 feet by 3 feet, so adding a little clearance is around 25sqft. 1 sqft is 7.5 galls, so I ft of water in a bridge hole is around 200 gallons. 200 divided into 100m gallons requires 5m feet of water of cross section equal to a bridge hole. So around 1000 miles length of water per day are required for 100m galls of water. Divide 1000 miles by 24hours and the speed is 40mph.

[furnessvale]

1 hour ago, Pluto said:

A narrow canal bridge hole is around 7 feet by 3 feet, so adding a little clearance is around 25sqft. 1 sqft is 7.5 galls, so I ft of water in a bridge hole is around 200 gallons. 200 divided into 100m gallons requires 5m feet of water of cross section equal to a bridge hole. So around 1000 miles length of water per day are required for 100m galls of water. Divide 1000 miles by 24hours and the speed is 40mph.

I'm having a little trouble with your dimensions and workings.

 

Even a tightly built canal like the macc, has bridgeholes 9ft wide and 4ft deep (more if properly dredged as would surely happen as part of a water transfer scheme.  Say 36 sq ft.

 

There are 6.6gals to a ft cubed so that figure helps your case, but applying that to my (opinion) more realistic cross section gives 237 gals.  Divide into 100m gals gives 421,940 ft length of cross section area equal to a bridge hole (I think a decimal point slipped in your calcs).

 

Divide down to the 24 hrs and you finish up with 3.33mph.

 

The full cross section of the canal would be considerably slower and I did say some piston relief work could well be needed in bridge holes.

 

Again I will double check after I have dined and may well be coming back with a totally different figure.

 

George

 

 

[mark99]

They just need to dredge the canals with a slope and the water will fall down to London.

[David Mack]

The Thames and Severn has locks about 12 ft 6 wide so presumably the bridges are about the same. At 4 ft depth that provides 50 square feet of cross sectional area.

The Llangollen flow of 12m gallons per day equates to 500,000 gallons per hour or about 80,000 cubic feet per hour. That results in an average speed through h bridges of 1600 feet per hour or about 0.3 miles per hour.

 

Or to look at it another way, a water speed of 1 mph corresponds to a flow of about 40m gallons per day.

[b0atman]

Forget HS2 the new tanker train will be H2O

 

 

[Pluto]

16 hours ago, furnessvale said:

There are 6.6gals to a ft cubed so that figure helps your case, but applying that to my (opinion) more realistic cross section gives 237 gals.  Divide into 100m gals gives 421,940 ft length of cross section area equal to a bridge hole (I think a decimal point slipped in your calcs).

 

George

 

 

Decimal points are always moving when you do calculations in your head, well in mine anyway. I still think that the flow in an open channel would be significant if moving significant mounts of water. The other problem is the cost of pumping when using an open channel which goes up and down locks, something which can be overcome to a great extent if a closed pipeline is used, especially when the delivery end is lower than the supply. Things could be improved if London's water usage was reduced - it is the highest per head of population in the country. They suggest that is because of leakage, but southerners just need to learn to live like the great unwashed in the north - and we have plenty of water.

[Machpoint005]

On 09/06/2018 at 16:03, Pluto said:

Such a scheme would probably make those canals used unnavigable. Surely the cheapest way to solve the water supply problems of the South East is to move jobs, and those that do them, to wetter, less inhabited areas.

Oi! We don't want another influx of Suvvennas in Manchester!

16 hours ago, furnessvale said:

I'm having a little trouble with your dimensions and workings.

 

Even a tightly built canal like the macc, has bridgeholes 9ft wide and 4ft deep (more if properly dredged as would surely happen as part of a water transfer scheme.  Say 36 sq ft.

 

There are 6.6gals to a ft cubed so that figure helps your case, but applying that to my (opinion) more realistic cross section gives 237 gals.  Divide into 100m gals gives 421,940 ft length of cross section area equal to a bridge hole (I think a decimal point slipped in your calcs).

 

Divide down to the 24 hrs and you finish up with 3.33mph.

 

The full cross section of the canal would be considerably slower and I did say some piston relief work could well be needed in bridge holes.

 

Again I will double check after I have dined and may well be coming back with a totally different figure.

 

George

 

 

If only we had gone fully metric, we would be able to do the calculations... if you want a speed in mph you can always convert at the end of the process, from m/s.

[Machpoint005]

On 11/06/2018 at 07:58, mark99 said:

3rd runway - lots of displaced homes. On that basis we assume those who object such things will refuse to fly Heathrow?

I never fly to Heathrow. I can get almost anywhere from Manchester without going to London, eg via Schipol or CDG.

[furnessvale]

3 hours ago, Pluto said:

Decimal points are always moving when you do calculations in your head, well in mine anyway. I still think that the flow in an open channel would be significant if moving significant mounts of water. The other problem is the cost of pumping when using an open channel which goes up and down locks, something which can be overcome to a great extent if a closed pipeline is used, especially when the delivery end is lower than the supply. Things could be improved if London's water usage was reduced - it is the highest per head of population in the country. They suggest that is because of leakage, but southerners just need to learn to live like the great unwashed in the north - and we have plenty of water.

I have been known to stand out on the towpath with a bar of soap in a torrential downpour to have a shower.

 

Certainly saves water, but I shudder to think what the washoff into the canal does for the wildlife!

 

George (northerner)

[Pluto]

Standing on the towpath washing means YOU are the wildlife.

[Peter X]

It surprises me a little that Londoners use more water per head, particularly if that statistic is for total use including industry, not just domestic use? I very much doubt that we use much more or less for washing!

I guess that if suburbia is included we use more water per head than other areas for parks and gardens, partly because our weather is warmer and drier than the national average. On the other hand millions of people in inner London have little or no garden, and to some extent we may be adapting to climate by growing more drought resistant plants such as herbs. My front garden never gets watered, it's mostly lavender and some big Mexican shrub that seems to laugh at drought. My lawn likewise, in a dry year it just goes yellow then recovers when the rain comes.

[Pluto]

Water usage statistics came from this https://www.london.gov.uk/sites/default/files/gla_migrate_files_destination/Water management report pdf.pdf

[mark99]

We London is covered largely by Thames Water who'se pipes leak like a sieve.

[Mac of Cygnet]

The three largest reservoirs by volume in the UK are in England.  The biggest by a long way (Kielder Water) is quite near where I live.  As it is almost at the very top of England, surely it should should be a simple matter to send the water down to London?