An Anglian water employee suggested changing the main water stop cock in the chalet that I visited. The incoming mains' pipe is black plastic that reduces to a small diameter internal pipe under the sink. We have lots of water towers around here to supply consumers. It concerns me that the towers are liable to imminent collapse what with all of those heavy aerials on the top.

Z.

In my teens and twenties I lived in my parents house that was supplied from a water tower, basically the same set up.

we had oversized water storage tanks in the roof and generally everything worked at our house, however neighbours complained so the eater board had a fiddle and upped the pressure.

As general builders we were going around replacing ball valves and installing hammer arrestors because of the issues caused by the higher pressure.

Eventually the water board dug a trench and linked two radial mains together to create a ring thus increasing the flow, then they reduced the pressure again.

Oh yes the water is mains' fed as it supplies the kitchen cold tap first. It is potable water.

You can get potable water from a tank (cistern) - originally it was covered by "Bylaw 30" of the water regs - basically it demands a bit of thermal insulation to keep the water cool, a lid and a few fly-screens over vent and overflow holes to prevent insects getting in. I'm sure the regulation has been renumbered by now, but the parts to convert a cistern are still often sold as "Bylaw 30 kits".

  - Andy.

 During the winter with the tank on the flat roof outside it may freeze.

Z.

perhaps instead of trying to boost the supply to individual chalets, you should look at restricting the flow to all the chalets using something like this Water Flow Regulators (robertpearson.co.uk), can be done at individual appliances or at the chalet stopcock position

Its a nice idea, but if it is anything like seaside places I have stayed at, I suspect there is no appetite to either spend much money or limit the "customer experience. " The real solution would have involved putting in fat enough pipes to deal with a bit of load creep from the outset. It is far too late ;-) 

Swapping the stop cock for a full-flow ball valve may increase the flow a bit relative to a 'tap' type of thing, but it is  not a big effect, the problem will be 10s of metres of 15m pipe, that should have been 50mm or larger.

when we do things like the taps at the jamboree camps we borrow techniques from the simplified designs recommended in 3rd world countries.  leads to a bit of a mis-sized design, but is quick and adequate.

example

And lots of normal design rules are irrelevant as it will all be rolled up and taken away after a few weeks. It just needs to be safe from an environmental health perspective.
Note that pipe resistance is not very like ohms law, it is non-linear, or the resistance is current dependent if you like.

The Hazen Williams approximation is commonly used for simple clean water pipe runs.

The coefficient C is perhaps 100-120 for a rough concrete pipe and 150 for a smooth bore plastic one.
The two killer facts are that the pressure drop rises almost as the square of the flow rate, so to double the flow in the same pipe almost quadruples the pressure drop;  and is divided by almost the 5th power of pipe diameter, so doubling pipe diameter gives you ~ something like 26 times the volume per minute for a given pressure drop.

The counterpart for wastewater would be
simplified sewage  less use on a camp but still OK for inspiration for initial estimates of pipe sizes to portacabin toilet blocks etc.
(think of a scout Jamboree with 20 thousand scouts...)

Mike

Well I would be giving thought to a communal water tower  or three .

Of course the basic premise is mere schoolboy physics and the towers if same height might have an interlink pipe too.

However thats just the physics of water level etc. Then you gotta consider "can it freeze" and water bye-law issues which might cloud the waters a bit. But might all beat re-piping in bigger dia bore