1) Negotiate with the landowner; 2) If negotiation does not work, then you can sue the landowner in small claims court for trespass. If the landowner is putting water on your land, that landowner is trespassing using water and the landowner is liable for damages. 3) You could hire a property lawyer to sue the landowner for trespass. Here is the cmall claims court information in PA:http://www.consumeraffairs.com/consumerism/small_pa.html
Good luck and I hope that you can resolve this matter.
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