They’re tidal. The areas with the plants don’t flood every day, else there wouldn’t be anything growing there at all, but I would guess they are underwater when the tide is unusually high. There is a dyke behind the photographer to stop the sea from flooding the farmland and industry here:
The photographer probably stood somewhere near the blue parasol icon. The green near the water is the green in Hanno’s photos, the grey road running east–west is on the inside of the dyke, which is the green line right next to the road.
This whole area has changed a lot since the war, though:
