Does the Breville Nespresso coffee machine have a plug or anything in the bottom? My machine is leaking from the bottom from a small neat hole directly under the water tank.

It is covered in this link

https://www.google.com/search?q=Breville+xl+830+drain+leaking+in+bottom+pan

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The seal at the bottom of the water tank is rotted out from age, you must replace the machine

Call the Nespresso Club for advice. You should have a toll free number for the Club, which is manned 24/7, and they're very knowledgeable and very helpful. Good luck!

Try gluing the seam with lock tight glue or similar plastic gluing compound. Let it dry overnight and try again.

These are available on line. Just search Breville, then enter the model number, and it should provide you with all the info you need.

I had the same problem. All of a sudden my kitchen top counter got filled with water. The water was leaking from the Nespresso C190 water resevoir at the bottom. Exactly where the reservoir meets the coffee machine base. I had by chance an "O" rubber ring left from a faucet which I inserted at the base of the water rervoir right on the small **** which when it sits on the C190 base lets a valve open in order the water to flow through. The "O" ring was 2 to 3 mm in diameter and about 1 mm thick, You might experiment with different ones until you solve your problem.

The Leakage in Nespresso Machine happens because some of the damage in components or seals in one of following
The water tank
Thermo block or heating component
Internal water pipework
This article might help:
https://coffeeabout.com/why-nespresso-machine-leaking/

I opened mine when this did this - it also happened to my second Magimix Nespresso Manual machine. A short pipe carrying pressurized water had burst. I called Nespresso . parts were not available and they offered me a new half-price machine. We are talking a 4 inch piece of plastic tubing here. Shame on you Nespresso for encouraging me to throw what is otherwise a fine machine....

I have a nespresso type D90 which does exactly the same thing so it is probably not just yours

800-562-1465 is the phone number for Nesspresso.
They can direct you to the local parts outlet.