The pipes are integrated into the ground. The tile is not done yet, there is yet a lot to be added, such as vines and undergrowth.
Overhead sprinklers would look weird on a 2D plane.
Here is a simple image edit of what I thought by the 2-part tile. I didn't want to make it too modular, as the blue marked box is the pump control system, and while the pump is running, the whole yellow-marked area becomes a quagmire (difficult terrain and -1 to hit to all present). Adding extra modularity, it can play too much to one gang's advantage. The pump has to be switched on first, and it is easy to switch it off once it is running.
While the irrigation pump is running, you can imagine there s a thick mist and powerful streams of water coming out of the cracked pipeline. And the ground becoming a slippery mush.