I see… Currents and waves are travelling in opposite directions. Thanks for.your detailed explanation!

Thanks for commenting! What I meant (but I see that this is totally not coming across from what I wrote :-)) is that the waves are coming in from the far right, passing underneath the bridge. On the other side of that bridge there is a large open space, so plenty of area for the wind to create waves on. By the time the waves pass underneath the bridge, they’ve had quite some time to grow. They propagate towards the lower left of the picture, where they meet a current. The current is fast enough to “sweep” the waves away with it, so they can’t propagate across the current. On the other side of the current, waves only develop slowly from local interaction with the wind, because (a) the fetch is not very large (they now have to start from scratch on the lee side of the current) and (b) that area is relatively sheltered from the wind by the bridge and shape of the coastline. Does this make sense?