Yeah I hope OP didn't use amnesiac system to sign that requires entering seed phrase everytime, his wallet is still intact in his device if that isn't the case.

Having 1 backup is no go, write it down maybe 3 times and store it in each different locations.

Pen and paper is cheap and it's not that much of work.

Despite storing in a metal sheet I also write it down in paper and store it in several places.

But I hope OP can recover the bitcoins.

Creating a wallet, making wallet backup, testing backup for recovery are all important steps to back up a wallet but it's not enough. To make sure that you won't lose all fund by a single failure of your device, one wallet backup, you must do make and save multiple wallet backups at different places.

How to back up a seed phrase.
Cryptocurrency security checklist.
The dos and don'ts of bitcoin key management.

The following article has important reminders about security and privacy.
Tips to avoid $5 wrench attacks.

OP you won't be needing the recovery seed until you want to import into another wallet,  so before the flood you have a hardware wallet or a hot wallet? And if the flood destroys the seeds you still have the devices right?

So you can still move the coins or edit your recovery and write it down again, I don't believe you lost anything unless you deleted it uninstall your wallet after you wrote down the recovery seed.

If this story actually happens for real then get a steel next time and use nail or sharp object to write your seed on the steel, water won't be able to destroy it again.

Well I will agree to some length bit still wonder if many don't secure their seed phrase or key by just keeping it in only one place or documents if it's written, such risk is not worth taken for me diversifying by having it two or three places possibly different locations but ensure its well secured because I know too well an African person hardly domicile only one place some have house in village as well reside in the city all this has way of keeping your key phrase safe if through the person want to safe gaurde. All this depends on individual and how it handle things natural disasters can happen at any time and may not take place all locations such can secure your investment without passing much stress of recovery if one throughly uses good safety measures.

You all talking about different locations like someone who have more than one house, the different location that's making sense here is to keep one in House A and keep another in House B.

Many people don't even have two houses, locations that you are talking about is still under one roof and what would the flood do?the exact result will unfold again, there is no point having all your seeds in different locations in the same house.

Now I need someone to tell us what to do in this situation then, don't just keep saying different locations it's not making any sense in this discussion.

But since OP seems down, I think he really uninstalled his wallet. I also think it's his only wallet or maybe his main. He should have memorized it if it's just his wallet. 24 words aren't hard to keep in mind, especially if you practice a few times daily. It doesn't take so much time either. It's even more secure from fire, water, or thieves. Unless you have a hard time memorizing, but still, that's just 24 words. It shouldn't be that hard with daily practice.

For OP, I'm sorry to hear that, but if you really don't know your seed phrase and have no way to access it, then your money is lost, that's it.

There is always a lesson to learn from most of the threads in this forum and for this one the lesson is that you shouldn't rely only on one location to hide your seed phrase, nowhere is completely safe from disasters, because a disaster hasn't happened where you wrote down your seed phrase doesn't mean that it cannot happen. If natural disasters like flood and earthquake doesn't happen man made disaster like fire outbreak can also happen so no matter how secured a single location is you should also find atleast one more location to hide your seed phrase. We as Bitcoin holders must be security conscious, your Bitcoin device can be lost or compromised at anytime and if you cannot account for your seed phrase all your Bitcoin is gone forever which will be heartbreaking.

Sorry to hear about your loss, OP, and this is another lesson for us to always keep multiple backups of our seed phrases in different locations because we never know what might happen. Natural disasters are a part of our world, and they could come unexpectedly sometimes, which is why we should always be prepared for such things and make sure that we either have enough protection for our important stuff such as seed phrases, or at least have multiple backups in different places, even better if it can be done in different cities so that if something happens in one city, the backup in the other city should still be available for you to use in such situations.

Another good idea would be to use metal for it. Engrave your seed phrase in the metal and then keep it in the safe, in that case, unless the safe itself gets washed away in a flood or something, it wouldn't be wasted even if water gets inside the safe. One can also dig a hole in the land and bury the seed phrase in it that is written on the metal, it should be kept inside something so that it can stay safe under there, and then it will at least be safe from such natural disaster. Just make sure that it is buried deep enough so that it doesn't come out after a flood or something, and once the water is out, you can dig it out.

I absolutely understand how you feel, but you can never kill yourself because you have tried enough to keep our investments details safe. But to the fact that nobody can easily predict what will happen in the next minute, that is exactly why it happened. At least you have learned from it, and I think you will definitely make more provision next time, because just like they normally say, "not where you expect is where you will fall", because at first you were even preventing fire without knowing that flood was around the corner.

It's actually a heartbreaking, but just keep pushing.

This is really unfortunate and I can imagine how painful it would be to lose access to your bitcoin in such a way, I know it would be difficult for you to ever think that a natural disaster can take away your seed phrase. Your experience is a good reminder that keeping a seed phrase in a secured place is not enough, having a proper backup in another place is very important. But please try not to be so down about this too much, you were trying to keep things safe and I hope you find a way to recover your funds.

So it is very important to have more than one secured backup in different locations, self custody comes with responsibility and experiences like this remind us that we should really take backup planning serious and fast before anything happens