We live on a hill. Due to poor lanscaping design our yard was not draining properly so we added a french drain. Now the lower neighbor is getting run-off and just complained. If we removed a raised flower bed border then the water would all flow downhill into his yard. With the border in place we use the fench drain to remove the water and send it out of the backyard. The water exit point is on our yard but does flow down onto his.
Are we obligated to respond to his complaint?