Hello Dhananjay,
After going through your query, I understand your grief about the destruction and the situation you are facing. I would like to offer you some advice that might help you out.
First of all, I would like to tell you to calm down as you are not at fault as the destruction has been done by a natural disaster, that is not under the control of an ordinary human being, and you have the protection by law that will save you from paying the compensation to the aggrieved family.
If the family files a lawsuit against you for the breach of the contract, then you can seek protection under Section 56 of the Indian Contract Act of 1872, which tells us about the Frustration of the contract.
Let me tell you what FRUSTRATION OF CONTRACT IS.
This is a concept that tells us about situations where the performance of the obligation becomes impossible. Here in your case, you can state this concept as the flood destroyed all the necessary things and equipment, the performance of the contract became impossible.
In this way, you will not have to pay the compensation to the family, and this will subsequently release you from liability.
You can also refer to the case of Satyabrata Ghose v. Mugneeram Bangur & Co. (1954), as in this case, the Supreme Court held that the contract can be considered frustrated if some unforeseen circumstances make the performance of the contract impossible.
At last, I would like to tell you that you don't have to worry about the compensation as you are absolutely not at fault. And please don’t forget to grab the evidence of the flood and its destruction.