Place bacon in a thick-bottomed 5 to 6 quart pot. Heat on medium to medium high heat.
Cook until lightly browned and the fat mostly rendered out of the bacon, about 5 to 6 minutes.
Remove all but 1 Tbsp of the bacon fat. (Do not put bacon fat in your sink drain, it will clog the pipes.)
Add the celery and leeks to the bacon and cook on medium heat until softened, about 5 to 6 minutes.
Add diced potatoes, chicken stock, water, 1/2 teaspoon salt, bay leaves, and thyme to the pot. Increase heat to bring to a simmer. The lower the heat to maintain a gentle simmer. Simmer for 10 to 15 minutes, until the potatoes are cooked through.
While the potatoes are cooking, prepare the salmon. Place salmon in a bowl, sprinkle with flour and black pepper. Toss to coat. Melt 1 Tbsp butter in a non-stick skillet on medium high heat.
Working in batches if necessary, lightly brown the salmon on one side, then turn over to brown on the other side. (The salmon doesn't have to be cooked through, just lightly browned).
When the potatoes are cooked through, use a slotted spoon to transfer the salmon to the pot with the potatoes, bacon, leeks, and stock. Stir in corn if using. Cook gently for 5 minutes then remove from heat. Stir in the cream and lemon zest. Add salt to taste.
Garnish with chives to serve.