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Is it common for people on city water in the US to have their own on-site pumping as part of the "standard" delivery system, or is the pressure usually entirely supplied by the municipal infrastructure/water towers etc? How much energy does this use?

What about other on-site costs that I might not be considering? I'm thinking of a low-rise building.

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    Towers or uphill reservoirs. Pressure is relied on to prevent contamination. If it fails they need to flush the mains. Oct 9 '20 at 2:41
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    I am not an expert here (but have a bit of knowledge about speccing water pumps). I expect that the answer depends on the pressure available on the building. For approx every 10 meters you loose 1 bar of pressure - and a typical pressure would be 2-3 bar - so I would expect a typical house would not need a pump but a low rise building would may - to provide reasonable pressure to the upper floors if its more then 3 stories or so depending on the lay of the land.
    – davidgo
    Dec 26 '20 at 3:20
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    In some municipalities it is illegal to have your own water pump if municipal water is available . Having a private water source competes with the municipal source and reduces its income. May 14 at 14:19
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Available data indicates that; 1) electricity usage for water pumping at homes is minimal; and 2) most municipal water systems provide more pressure than required for residential uses

Is it common for people on city water in the US to have their own on-site pumping as part of the "standard" delivery system?

The U.S. Energy Information Agency's 2015 "Residential Energy Consumption Survey" (RECS) includes data on electricity end use by category:

Residential electricity consumption by end use, 2015

Water pumping is not a specific end-use category, so would be lumped in the 13% of "not elsewhere classified," which would also include rural homes that pump their own well water. We can assume that across all homes, water pumping doesn't represent significant usage, otherwise it would likely have it's own category. So pumping water is probably going to represent less usage, on average, than each of these (source):

Category kWh per house per year using the end use
Microwaves 123
Dishwashers 113
Pool pumps 1527
Hot tub pumps 305

Or is the pressure usually entirely supplied by the municipal infrastructure/water towers etc?

Data on municipal water supply pressure standards is hard to come by, but a 2016 paper from the American Society of Civil Engineers provides some interesting details: "Pressure Standards in Water Distribution Systems:Reflection on Current Practice with Consideration of Some Unresolved Issues".

It would seem that most water delivery systems (WDS) in the U.S. supply sufficient pressure for residential uses because there is a higher-pressure constraint: fire flow. Fire flow is water drawn by sprinkler systems and fire hydrants, which require a certain minimum pressure in order to function properly. In fact, meeting fire flow requirements can cause other problems (emphasis added):

Although a [minimum pressure constraint] is enforced in WDS design to ensure supplying adequate demands during periods of peak consumptions (e.g., the greater of the maximum hour demand and the maximum day demand plus fire flow), many systems experience higher pressures than necessary during off peak demand periods. This is so much so that, in certain instances, residential customers might need to install pressure-reducing valves in their homes.

A 2014 paper found that most utilities agree on a minimum pressure requirement, but don't track high pressure events. From "Survey of pressure management in water distribution systems":

Although the majority of utilities recognize the need to maintain distribution system pressure of at least 20 psi under fire flow and emergency conditions, most have no goals to control high pressures in their distribution systems. As a result, their systems are at increased risk of water loss, main breaks, and infrastructure deterioration because of the lack of an effective pressure management system.

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Depending on where the houses are located; in the Mid-West USA, flat ground and raised water towers means most of the water is gravity fed (with only the initial pumping to get the water into the tank).

In my city (Southern California, USA) approximately 40% of our water is gravity fed, the remaining 60% has pump that feed and fill tanks upon the hill, which then are gravity fed back to the upper houses. There is approximately 500' (150 meters) difference in elevation between the purely gravity fed homes and the "pumped to" homes (the upper homes have up to three pump series to get the water into the upper tanks).

Essentially if your home is not directly downhill from a water source treatment plant, your home is being supplied by water which had to be pumped at some point.

There are rare cases where additional private homeowner pumps have been installed where the municipal water pressure was lower than expected (we have a few areas like this).

Depending on how low the initial pressure is, the cost of these pumps is minimal in electricity compared to the initial cost, maintenance, and replacement of the pump itself.

Short answer is it is not common to have an additional private pump system, but if you do, the pump is fairly small so electrical usage is low.

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