water , sewer , and gas infrastructure ?

Thread Starter

Mathematics!

Joined Jul 21, 2008
1,036
I am curious of how the infrastructure of these systems are from outside the house to the gas company , water/sewer company. I already know the infrastructure of building/commercial/residential housing of these systems but am now curious how the rest of these systems back to the supply companies.

I know the pipes get bigger as you get farther from the house I would imagine. In houses you typically have the 1/2 in pipe for water , sewer can range 1 1/4 , 1 1/2 , ...etc but farther out the bigger. Gas I am not sure if the pipes get alot bigger as you go out.

Questions
1) water infrastructure : what are normally the size changes of pipe going from the house back to the supply company. And how do they typically connect these I would imagine it would be different the how home pipes are connected with solder , or pvc primer/glue but maybe I am wrong. For gas I would imagine the pipes no matter what sizes would have to be thread on based or clamp screw down based.

2) Other then the pipes themselves back to the supply company and maybe the meters / shut off valves along the way is there any other devices needed in between the house/building and the supply company?
Or is that pretty much it. I would imagine depending on how close you are would determine the pressure you are going to get so is there pressure reducers/ amplifiers/pumps or are these devices normally installed at houses not the infrastructure before the endpoint.

3) For people that work for the utility companies water/sewer , gas , electrical is there any tools need that one couldn't get at a home depot or harbor freight to do repairs on the big infrastructure based fixes of the systems. I know for the most part if you are doing building/home repair / installations home depot or other building suppliers provide mostly any tool that you would need to fix anything at the house/building level but when it comes to passed the house back to the generator , supply pump ,...etc of the supply company I am not so sure. I would imagine in most cases they would just need bigger versions of the same tools , bolts ,...etc

But maybe closer to the company they uses specific proprietary tools , bolts so it would make it harder for one to muck with the system.
But if they did that then there would be a small learning time for seasoned electricians , plumbers to get uses to the non-traditional tools if they wanted to work for the supply companies them-self instead of residential home building.

My thought on this is it would be ok provided they only changed the bolts or small changes which do not effect a total new theory/knowledge of how the system works. If it took different theory of how it all works then it would take electricians , plumbers a steeper learning curve as opposed to just learning a few new bolts..etc. And from the electrical engineers that build the systems infrastructure I would imagine they want to keep it as simple as possible for repair/installation/customization/training. And also for the project managers that have to keep the workers working / doing the correct things in collaboration to build the system in a timely fashion. Say 100 man days for example


Hope there are some utility people that can elaborate on this interesting stuff
I would be very happy to know the whole infrastructure at a high,medium,and low level outside the home.
 
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MaxHeadRoom

Joined Jul 18, 2013
28,704
For starters a residence usually has larger than 1/2" for water supply, 3/4" min.
As a general rule, anything from residence up to the disconnect or meter, water gas etc is the responsibility of the home owner, after this the municipality or service company.
On a side note, the water supplies for many years between the service and the dwelling was of metallic in origin, and the electrical service used this as the local Earth Ground, with the advent of composite materials used for water supplies, it required the use of a Earth leakage trip or similar device to be used at the service entrance in conjunction with ground rods.
In the case of implementation of gas, it is required that the amount of pipe junctions be kept to an absolute minimum.
Obviously there are also many other regulations regarding natural gas.
Max.
 

Thread Starter

Mathematics!

Joined Jul 21, 2008
1,036
Ok but was kind of wondering the infrastructure of the gas , water/sewer.
If it is anything like the electrical infrastructure then there is a transmission and distribution sector with sub-stations that lower or higer the pressure thru pumps.

For gas if you are correct with them trying to min the number of connecting pipes reaching you from them. Then the distance between you in them would be a big factor. Curious is there like a diameter max supported for gas company customers before another gas company supplier must be created for the customers outside the diameter. Because you can only make long large pipe in all one piece so big before you must join?

The other question is about once the water is used from your house and goes into the sewer. Does the sewer system have any pumps to pump the dirty water back to a water sanitation company or do they just rely on gravity to get it back. Also I would imagine there is a max distance one can be away from a water sanitation plant before the resistance of the pipe to the pressure of the new waste would be an issue to get it back to the company. (Thats way I was wondering if there is some pumps or on/off valves for the sewers like there is for the clean water supply lines)

My understanding is you can either be totally disconnected from the sewer company and have a standalone leech field/tank or you can have a sewer drain that drains directly into the sewer lines back to the sanitation company. (of course for storm/gutter drains and excess clean water/environmental water one could just have a storm drain to a pond or other system since it is not going to hurt the environment/not polluted .
 

tcmtech

Joined Nov 4, 2013
2,867
The sewer systems have smaller lift stations all over the place. There could be one next to your house and you might not even know that it is what it is.

If you have ever seen what looks like a large round or rectangular vault along a street that has a fair sized electrical panel with a set of lights on it and in many cases have a sort of small single arm crane or lifting hoist permanently mounted to swing over a manhole cover on the vault the odds are thats a local sewage lift station.

Smaller ones look similar to this.

Lift station img.jpg
 

Thread Starter

Mathematics!

Joined Jul 21, 2008
1,036
So the lift stations are like the pumps that pump sewer back to the waste treatment company and the picture you showed me is one of these.

Cool makes since that you would need pumps both for sewer and clean water supply lines at some point. Gravity can only do so much i.e toilet to street eventually for longer runs pipe resistance would be an issue...

Curious normally is the water treatment/water supply companies the same company as the waste treatment companies. Basically are they pumping waste back to the suppliers or to a different location for waste treatment. ( I guess I should phrase this normally since it could be done anyway they wanted to)

And if a different location is it owned by the same water company ?
 

sirch2

Joined Jan 21, 2013
1,037
I can't speak much for the USA situation but I used to work for a UK Water/Waste Water Co. Here we use gravity as much as possible, the electricity cost is 40% of the domestic water bill, water is heavy. So sewage treatment plants are next to rivers generally lower down stream than a town. Water treatment plants are, where possible, at the higher part of a town, close to a reservoir or river. Treated water is pumped up into a service reservoir or water tower from where it feeds the town by gravity. As tcmech says, wastewater may require intermediate pumping to get it down to the treatment works.

As for pipes there is a huge range of sizes. Sewers are not generally under any significant pressure (most only flow part full) and are generally, clay, concrete, brick etc. I have walked though some London Sewers and some are vast - 10 or 12 feet. Potable water pipes are under pressure and for larger sizes they were mainly ductile iron but plastic is much more common now for sizes up to around 12". Iron pipes have push-fit socket joints, even in sizes like 42" and they are an absolute pain to "push" together. Plastic pipes are often heat welded.

Pipes are sized to suit the requirement, friction losses are higher in smaller pipes and at higher flow rates so bigger diameter pipes are more economic than lots of small pipes.
 

Thread Starter

Mathematics!

Joined Jul 21, 2008
1,036
One other thing is in the sewer pipes I would imagine you could run into the same problem as a septic tank/leech field system where the solids need to be pumped out of the systems. If correct how often does this happen and where do they go to clean this out. Like does the lift/sewage pump stations ever get clogged with to much solid waste not breaking down.

And I get that they uses gravity alot and pumps and the location is at the lower points near rivers ,...etc all makes since. ( the clean water treatment places at the top land...etc )

But what about solids in the sewer systems how are these dealt with normally.
And if pumped out where do they dispose of it and how.

Maybe this is not really an issue since 95% of the stuff is either paper based , food based , cleaning based (tooth paste ,cleaners ) and crap which seems to all break down into liquid pretty quick I would imagine. Though maybe there is to many people using that could effect the rate of break down
 
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tcmtech

Joined Nov 4, 2013
2,867
Most of what you find in sewage is soft solids or items that can easily be chopped up and broken down by the effluent pumps at the lift stations.

From there it's at most a runny sludge with fine solids in suspension that easily flows through the piping systems.
 

sirch2

Joined Jan 21, 2013
1,037
Sewers are generally laid at gradients that ensure self cleaning, i.e. the velocity is such that it will move the solids down the pipe. Egg shaped pipes are also used (narrow at the bottom, wider at the top) to ensure good flow rates at flow volumes. As tcmech says macerating pumps are often used to break up the solids at pumping stations.

Fat is a big problem though, people and businesses tip hot fat down the drain which then cools and solidifies in the sewer. Because it floats it tends to stick to the walls and crews do have to go in and shovel this out.
 
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