Water ingress from adjoining property

Other

The party wall of a terraced property I rent out, has damp from floor to ceiling. I have been told by a surveyor it is probably due to the neighbours boiler or bath seal leaking.
The tenant has recently moved out telling my tenant that she was going because of the damp and the landlord who lives in Spain does not want to know.
The surveyor who looked at the wall said the wall could be tanked but this is not a full solution the water ingress needs treating. Do I have any way of finding out who the owner is and compelling him to repair the leak or leaks?
Thanks
Lynda Grundy