Hanuman Digs Water Well

Kesari orders to dig a big well in Sumeru so that the problem of water shortage can be dealt with. Hanuman also wants to do something for his state and requests Kesari to take him to the place where the well digging work is going on. Hanuman on seeing that some problem has halted the digging process, uses his superpower to dig the well. Why is Atibal seeking Hanuman's help?