The water race and helpful chickens

I have a water race at the far end of my back paddock.  Somewhere uphill to the north, there's a river and some of the water is redirected down this water race.  The neighbours have animals grazing in their paddocks, and they just walk up and drink from it.   And through it, and back, and certainly defecate in it while they're there.

Unfortunately, as time passes it fills in with muck the animals send downstream, the clay at the sides eroding and water weeds growing on top, and it fills in. The end result is that the water is now at the level of the ground alongside the water race, and it floods areas of the paddock.  At this point it needs to be dug out.  If I had grazing animals in my paddock, I wouldn't have this problem. What I would have though, is grazing animals rubbing up against and breaking my orchard trees.

Here's a comparison shot which shows my dug out area on the left, and the overgrown area on the right.

The length I've cleared so far.  Really, in an ideal world I'd dig it all a meter wide all the way along, and I'd do it while it's all sodden from being flooded all the way along.  But in this world, the less hours I spend digging muck is better.

The area on the right-hand side between the olive tree and the water race, back to the fence was the where the worst of the flooding was.

What I really like though, is the brown area in the foreground.  It's where the chickens have scratched the grass clear and now there's hay on top of powdery dirt.  This is a huge advantage to me for the upcoming spring, as it means I don't need to clear grass to make new garden beds.  The area ahead will likely be used to plant bloody butcher corn or a range of broad bean varieties.  While they've scratched up that area all on their own, I might see if I can start sections in the foreground and get them to clear more of that area.

Here are the chickens at work scratching up another area of grass they've already cleared pretty well.  This area and all around where I am standing to take this photo will likely be where I plant a wide range of pumpkins, all of which are cucurbita maxima varieties.

Some time in the coming week, the chickens will be getting treated with diatomaceous earth.  This involves putting them up to their necks in a pillowcase, and shaking the pillowcase around them.  Classic internet advice.  Maybe it will work, or maybe it won't.