@StLL
Farmers usually have a lot of extra food, but low on money as selling food is their source of income.
In medical times the big cities were almost always sounded by farmland that supplied the city itself with food.
It's not that unlikely that because of the flood transporting the food to the city has become a problem for them, so they are unable to buy materials for the repairs.
Also, we don´t really know how big the flood really was, it doesn't have to be on a huge scale for it to be a big problem for a few farmers.
@anggitoz
well, depending on how he does it, it's possible to do without a pump.
If there is ( or he can create ) a plot of land on a lower altitude/hight then the dungeon, then the water is naturally going to flow there because of how water pressure works.
This is why water towers are always placed on mountains and stuff because you don´t need a water pump and only need to open the faucet to get water out
( still might need a pump to get it inside the tower though )