Transformer Foundation and Drainage

That is NOT enough information for any knowledgeable answers.

You should consult a LOCAL civil engineer and do the installation correctly, instead of trying to do it on the cheap.

Transformer Basics-Working principle, Construction, Types, Applications
Controlled Drainage – Transforming Drainage | Project Funding

Of course the design of the transformer foundation and surrounding area are key. The foundation should not be in a drainage of low spot. Uphill from the site should be addressed first to make sure any water (runoff or otherwise) is properly diverted around foundation. Gravel and French drains are mandatory to keep site dry. Any water piping should go around the site. Water will not stay in pipes forever.

I wouldn't put the opening of a drainage pipe above a transformer.

Good practice requires knowing the local codes where this transformer resides. We don't know your location to tell you what your local codes say.

Above the actual transformer, or above the transformer bund wall? Much assumption and misreading being accounted in this forum.

You said 'Much assumption and misreading being accounted in this forum.'

Well what do you expect when you only give a bit of the story? If you are a regular visitor to our little band of misfit engineers, who like to exercise the grey matter muscle, that grey matter does tend to run amuck, at a tangent, without proper data, facts and figures!

We will assume the unseen, unread and unannounced, then concoct a wonderful story to suit our imagination!

So tell us the truth, the whole truth, and nothing but the truth and we will attempt to give you the benefit of our collective years of experience!

If you can't....... expect the worst!

"Is it a good practice to keep drainage pipe below the foundation of transformer?" No interpretation required. Clearly the answer is Yes or No.

I agree, the English language is most confusing and assuming. Even more so for the English.

Above the actual transformer, itself is not a good place for the drainage opening. I was dissuading the OP from this ridiculous option that would funnel the runoff to the worst place possible.

As for others concerns about putting the drainage pipe below the foundation, I can think of situations where this would be preferred. This is particularly true if the drainage pipe is part of the initial transformer and bund installation. If instead this is a drainage upgrade on an existing system then this still might be the best option but can easily induce unforeseen complications. In either case, the licensed engineer site plan based on the geological/hydrological survey should be followed!

Ye Gods... re-route it so you don't have to dig beneath the foundations!

surely you cannot be that blind to the obvious!

Pipes eventually require repair. It would be better to not have to dig up the foundation if possible to repair the pipe.

Also, if the pipe leaks, you run the risk of undermining the foundation, also not the best to assure service continuity.

Is the transformer pen fully tanked? If not oil seepage can get in to water courses. I don’t know the laws in your country but here in the UK you would be facing enormous fines imposed by the law courts.

25 years ago our company contaminated water courses with quarry slurry. The courts imposed a fine of £1.25M, added to that was the clean up bill.

Think long and hard about what you plan to do.

If the transformer, (and it should be), is fully tanked with oil, the bund should be of sufficient capacity, that is, at least 10% more capacity of the transformer tank and reservoir tank on top of the tranny. This is the same in all countries, including the UK.

To install drainage below a tranny bund is acceptable and normal in may builds, espcially substation drainage, as long as the clearance is sufficient and the rainwater drainage does not flow into the tranny catchment tanks that may be installed, The tow drainage systems must remain separated and never connected to one another.

If the bund exists, a direction bore could be used to go underneath the transformer bund. It is not a good idea, but Yes, it can be done ad it is not an infraction of any rule/laws. it may be odd, but it is prefectly fine to do so as rerouting could cause a flood in a station or undermine gantries and equipment.

Agreed, information is insufficient and only the poster knows his conditions, risks, and station layout, and enviro. It may be his only option to go below the tranny bund.

No there is not enough information.

We have pipes that are well over 100 years old as well as pipes that are well over a hundred feet deep as well as pipes that are layered between multiple utilities.

Rerouting and making turns that are not necessary exasperate issues that otherwise would have not been.

If done correctly. The infrastructure will outlast all of us.

If installed incorrectly it doesn't matter where the pipe or the transformer is located.

How many pipes and utilities cross at a 90 degree angle above and below each other?

If none of it were permissible and all of it was deemed a bad idea... Nothing would ever be accomplished.

Hundred year old pipes are made of what?

You name it.

How about, rusty steel, concrete, and lead. And 100' down, I imagine gravity.

Yes indeed. And right outside some 1800 era water main was replaced last year.

I was surprised at the decent condition of sections.

We also have brick pipes.

Most homes in my neighborhood are well over 100 years old.

The deep tunnel drains can be over 300' deep . Not as old, but under everything.

The intakes for the city water are a modern marvel of yesteryear.

New would be nice.. and expensive.

I can count on on one hand with no fingers or thumb the number of times I've witnessed new work undermined by a sinkhole.

I would expect that the excavator drivers sphincters are pretty tight, and adrenaline is brown

The excavators always seem to have holes in the seat,even new ones.

I asked why,and was told that the sphincter muscles were very powerful under stress and kept pinching holes in the seat covers.

100 Year old clay.

I have been involved in construction work at power plants where digging any hole resulted in a change order because of buried treasure. These plants were only 30 years old but not much was done to track buried utilities. After the initial construction was complete the original construction office trailers were buried on site because it was cheaper than moving them.

Something I have notice about American companies and military, they throw equipment away and leave it behind without thinking anything of it. Where, in all other countries I have worked, equipment is removed, including brick buildings and foundations and all is reused or recycled elsewhere. And left over aggregate and sand is donated to the community, they just arrive with a pickup, shovel it up and go build something at home. Even spoil gets collected by the community and used as fill for building sites for anyone who needs it.

You guys certainly throw away a lot of money and the client at days end, pays for all that waste in the initial costs. Like the UK, you seem to be a 'throw away society' or, your material are so cheap and profits so high, you can afford to waste. Bemused by these actions. But I guess you mark up the buried treasure on site plans!!!!!! Of course it is marked up.....

Usually the markings are just graffiti.

When a train derails in the USA,sometimes the entire cars are buried on site beside the tracks to save the money for hauling them away.What a waste.

Since the 1970's transformers are required to have retainer wall around their bases.

Gates in the wall were allowed to pass rain water but required to be closed at the first sign of an oil leak.

This was to prevent PCB Contamination of the environment.

The PCB oils were heavier than water,and would quickly sink into the ground.

In regard to old underground pipes,there is a method now where they inflate a long plastic liner into the tube without digging it up.

This method is being used in many cities now.

Tunneling under a transformer is not a very good idea. Redirecting the route from the beginning to avoid it is the best way.

Don't be penny wise and pound foolish.

Apparently you are not very proud of your question, #1.

How about providing a Site Plan, with all existing relevant water course(s), and all appropriate cross-section(s), etc., with all relevant dimensions and elevations, with enough relevant details, features, info, etc., included to define the situation well enough for us to make specifically relevant suggestions, instead of just trying to make intelligent guesses?...

If <...We have to...> then <...Is it a good practice...?...> doesn't matter.