Talk:Water tower

It seems to me that the statement, "...constructed at a height sufficient to pressurize a water supply system...", does not go far enough in explaining the main purposes for using a water tower in modern water distribution systems.

First and foremost, a water tower is a PRESSURE REGULATOR with no moving parts. When a fluid, like water, is pumped with a mechanical pump there can be unacceptable pressure fluctuations. Water, like most fluids, is not compressible so when there are no open faucets in the system, the water pressure can very quickly go very high with a piston pump. Perhaps even high enough to break the pistons or cylinders. So the pump must be stopped almost immediately when the flow is stopped or decreased. And the pressure will go down very quickly when the pump is off and the faucets are opened so the pump must also be restarted very quickly when the pressure drops. This is a very difficult thing to accomplish with mechanical devices.

By storing the water at a relatively constant height in the tank of the water tower, the pressure in the pipe leading to the faucets is also relatively constant. Thus, the tower acts as a pressure regulator and there are no moving parts to wear down. And the pump can be run for relatively long periods to bring the level in the tower up to a high point and then shut off until it drains to some mid point. Thus the pump runs in a better cycle. This greatly simplifies the design of a water distribution system and lowers the cost of maintenance.

The second main reason for water towers is to provide a emergency or back-up supply of water for conditions when it can not be pumped; such as a power or pump failure. This provides time for the maintenance personnel to repair the problems with no interruption to the flow of water to the customers.

The height of the water level in the tower determines the water pressure at the base of the tower. The formula for this is:

Pressure in PSI = 0.0360911906567 PSI X height in inches^[1]

The pressure will change by about five to fifteen percent with most towers as the water level changes from the highest to the lowest level, but this is far less than the fluctuations that may be present without it.

The water tower must be higher than the highest point where water is to be distributed without any additional pumps. Thus many high rise structures that exceed a significant fraction of the height of the local system's water towers must have their own means of pumping the water to the upper floors.

These are the two primary purposes of water towers.

I hesitate to edit the basic article, but offer this so that others can consider it in future changes.

EPA3 (talk) 06:31, 25 December 2014 (UTC)

You should go ahead and edit the article, per WP:BOLD. Dicklyon (talk) 06:42, 25 December 2014 (UTC)

As quoted from the article: Alternatives to water towers are simple pumps mounted on top of the water pipes to increase the water pressure.[31] This new approach is more straightforward, but also more subject to potential public health risks; if the pumps fail, then loss of water pressure may result in entry of contaminants into the water system.[32] Most large water utilities do not use this approach, given the potential risks.

Here’s what I would say to that:

A Server Administrator’s approach to this problem:

Have two pumps side by side that are in-line for supply (via a splitter with valves), and output (via a splitter with valves), but not in-line with each other. Both have capacity that far exceeds normal throughput. Both operate all the time, but at half capacity (slower, but lines still fully charged), so the combination output equals 100 percent. Should one pump fail the other ramps up to full 100% capacity immediately and automatic valves isolate the bad pump side until fixed. Sensors automatically alert the Water company to start the fix. Have two pumps ready in reserve for immediate replacement, re-order new pump to restock while still having a backup just in case. Result, no downtime, no loss of pressure to allow introduction of contaminants, no loss of service, no loss of capacity. Problem solved.

BTW, This would surely be much less expensive than the cost of a water tower! Indigob2016 (talk) 04:42, 4 March 2016 (UTC)

Pumping stations generally do have two or three pumps and a generator. Some small systems don't have any elevated storage and are able to get by like you describe. It's still better to have a tower. The tower gives more regular downstream pressure than is possible with pumps. One of the problems with using only pumps is, there is a relationship between pressure and flow rate, you can't increase or decrease one parameter as you desire without affecting the other parameter. The controller can only increase or decrease the pump speed. Pumps are not equally efficient throughout their whole operating ranges; they have a best efficiency point. If operating very far from the best efficiency point, the pump might even have problems like cavitation which will damage it. A system with a water tower will be designed to keep the pump operating as close as possible to the best efficiency point at all times while the pump is on.

Another issue with having the pumps run all day long every day, is they wear out faster. Pumps are very expensive and the purchase of a new set of pumps is a big capital investment that may require months for delivery. You generally can't order a new one immediately when one breaks.

Another alternative to a water tower, is to use a tank at ground level which is pressurized with air pressure (called a hydropneumatic tank). These can have a bladder to separate the air side from the water side, but more often it's just an air-and-water tank with no bladder. The volume of the tank helps even out fluctuations in the system pressure just like a water tower would, but they tend to be a lot smaller because they have to be pressurized (thousands of gallons, instead of hundreds of thousands of gallons), and they won't cut it for big systems. Baller McGee (talk) 19:30, 3 March 2023 (UTC)

This article starts: "A water tower is an elevated structure supporting a water tank constructed at a height sufficient to pressurize a water supply system for the distribution of potable water, and to provide emergency storage for fire protection." Why the qualification "potable"? What about a water tower to provide water for steam locomotives for example - clearly potable water wasn't required, nor were they for water protection. Suspect you'd also find water towers at some industrial sites, etc. to provide water for manufacturing processes, etc. In any case, this lead sounds a lot like original research to me... — Preceding unsigned comment added by 68.50.90.64 (talk) 21:18, 7 January 2017 (UTC)

In the title and list of contents, the word "Weird" is misspelled as "Wierd" (but the correct spelling is used in the text). I would change this myself, but it's a title and is presumably linked to the list of contents, so I'll leave this to someone with the necessary technical knowledge.84.243.236.9 (talk) 14:57, 14 March 2019 (UTC)

The article starts off mentioning that the terms "water tower" and "standpipe" can be used interchangeably, and then goes on to have a whole section devoted especially to "standpipes". This certainly needs some explaining. --BjKa (talk) 22:45, 8 May 2019 (UTC)

It's a very generic term, "a vertical pipe that is connected to a water supply". A standpipe may not have a significant amount of storage but is used for pressure regulation, an example being Philadelphia’s Spiral Standpipe. Larger diameter standpipes could also store a volume of water, they were later called water towers when they were built with long metal legs instead of a single pipe rising from the ground. Dougmcdonell (talk) 00:53, 13 November 2019 (UTC)

In that case - why does the article say that very few standpipes remain? I see "standpipes" (that is, cylindrical water towers) all over the place in the midwest. John D. Goulden (talk) 19:33, 17 June 2024 (UTC)

The cited references don't support that claim either. It looks like someone added a note about elaborately decorated Victorian-era standpipes in St Louis many years ago, with sources saying that not many are left, and over the years that statement was edited to broadly claim that very few of any standpipes are left in the US (which is obviously untrue), but still citing those St Louis-specific references.

That section should either have some discussion of old-fashioned standpipes in early city infrastructure vs modern usage in rural areas, or else that claim should just be removed entirely. FlyingScientist (talk) 00:44, 20 January 2025 (UTC)

this table should have a column for actual water tank height. The water height is unlikely to be much over 100m (for feeding a public water system) as the pressure would be too high. Gjxj (talk) 12:37, 22 January 2020 (UTC)

The "Pinnacle height" column should be changed to "Greatest height at which water is stored."

For example, the Swisscom tower, currently "tallest" in the table, reaches 250 m only because it's topped by a 98 m antenna – which has nothing to do with the tower's secondary function of water storage. For those interested in the heights at which towers store water, the 250 m figure is irrelevant.

The "tallest table" section on this page argues for the same thing, using a different argument. 2601:281:D47E:1920:81BB:8350:3633:63F2 (talk) 01:10, 13 October 2022 (UTC)

There were notable and interesting uses of water towers in ancient times, and the History section should not gloss over this. For example, there was a water tower 1700 years ago at Mediana – and that was probably not the first. 2601:281:D47E:1920:81BB:8350:3633:63F2 (talk) 01:17, 13 October 2022 (UTC)

I am requesting clarification on the (uncited) "tall, exposed, N-shaped" standpipes used in the United Kingdom in the 19th century. In what way are they N-shaped? Uppercase N or lowercase n? My conception of a standpipe is just a vertical cylinder extending up from the ground to a great height. Baller McGee (talk) 19:58, 3 March 2023 (UTC)

Reverted to the old image since there didn't seem to be a reason to change it, but the replacement of the old image seems odd to me. Is there any reason why the old image was replaced with two images of water towers with cellular equipment on them? jan Janko (talk) 01:40, 7 August 2024 (UTC)