Land dispute. Rights of Ingress/Egress owners. Who has the say on what can and can't be done?

We own property in Alabama. The man behind us is telling us that we can't dig a ditch to stop the flooding that the road he put in to his property has caused. He has to cross us and another neithbors prop. in order to get to his land. We can not land lock him, Survay gives a 30ft. easement (15 us and 15 neighbor) . Was told that sense the road he put in caused the flooding problem he is responable to fix the problem. The problem is HE thanks that he has the right to tell us we can't do anything with the prop. but he can. Keep in mind the majority of the easement (right of way) is on us and the other neighbor. This all started due to us wanting to stop the flooding HE caused. By the way he has only been living back there for just over a year. We have been here for 15. The land has been in the family for over 40.

If you know the laws in Alabama about land. PLEASE help.