Take out a thick-bottomed 5-6 quart pot, and place the bacon in it. Heat on medium to medium high heat and cook until it's lightly browned, and the fat is mostly rendered out of the bacon. It will take about 5 to 6 minutes.Remove all but one tablespoon of the bacon fat.
Add the celery and leeks to the bacon now, and cook on medium heat until it is softened. It will be about 5 to 6 minutes.
Now add the diced potatoes, chicken stock, water, 1/2 teaspoon salt, bay leaves, and thyme into the pot. Now increase the heat to bring it to a simmer. Then lower the heat to maintain a gentle simmer. Simmer this for 10 to 15 minutes or until the potatoes are cooked through.
Now prepare the salmon. Place it in a bowl and sprinkle with flour and black pepper. Toss it and coat it. Melt 1 tablespoon of butter in a non stick skillet on medium high. Work in batches if needed, lightly brown the salmon on the side. (Salmon doesn't have to be cooked through.)
Once potatoes are cooked through use a slotted spoon to move the salmon to the pot with the potatoes, bacon, leeks, and stock. Stir in corn if you are using it. Now cook gently for 5 minutes then remove this from the heat. Stir in the cream and lemon zest, and now you can add salt to taste.
Now garnish with chives, and serve.