This is a 125 feet long swale! Swales are a permaculture technique that catch water run off in a level trench with a berm that can be planted into, the water then stay put for the plants to drink from. This is helpful for the plants, but also stops water run off from going where it’s undesired, and in this case helps a lot with storm water management. Before this the house’s crawlspace kept filling up with water during a heavy rain. This swale, along with a few other earthworks, should solve this issue. Yeehaw!