I am on a corner lot and my backyard receives water runoff from my neighbor behind me and my neighbor beside me. I have a french drain installed where the backyards come together and didn't have much of an issue, but then I installed a fence on a downsloping part of my backyard that presented some water pooling issues (see thread here). I was able to get the fence company and come out to shave off an inch or so of the fence on the problematic area, but I still feel like I will need to help this area with drainage as much as possible since water will always continue to flow this direction.
Here is a quick mockup of how the water affects my backyard as well as some draining issues I have in place.
The yellow square is a basin that routes to the street. It does a good job with most of the water that comes from my neighbors yards, however I still have issues with natural runoff. The good thing I notice is that it runs along the backside of the fence, into the back right corner, and then flows down to the closer right corner (blue arrows). The area between the back of my trees and fence line has become somewhat of a valley allowing for water to flow through it. I will likely build a dry creek bed for this, but I also feel like this is an opportunity to do a river rock type of border along the fence that might help, but I don't really know anything about landscaping.
Problem: Water flows (and sometimes pools) on my fence line.
Question(s): Would installing a river rock border help alleviate this at all? Would excavating the grass and playing river rock down be a solution, or would an actual trench need to be dug? If a trench is dug and there's also a gap under the fence, how can I keep rocks from falling out of my yard?