Preheat oven to 375 degrees. Cut bacon strips in half. Open and drain water chestnuts.Wrap each water chestnut in 1/2 strip bacon. Secure with a toothpick and place in baking dish. Bake for 20 minutesIn the meantime, in a mixing bowl, mix together the brown sugar, worcestershire sauce, soy sauce and ketchup.Take wraps out of oven and drain off some grease. Pour sauce over the top and place into oven for another 30-40 minutes. Serve immediately.