Carpenter ants clean up rotting wood, not healthy wood. Being near a lake you probably have wood that is moist a lot of the time?? Is there a possibiilty that you have a leak somewhere? There is DE, orange oil spray, hot pepper spray and vinegar wash as a solution. Also a diluted application of Dr. Bronner's peppermint soap & water.
If you have a lot of moisture around the base of your home, try some plants that need a lot of water to help keep it more dry. Elephant ears are used for this often, but they spread and if they get out in the wild they wreak havoc. Check out Aquarena springs in San Marcos to see what can happen when they go wild.
Boric acid is never recommended for outdoor use as it will alter the soil chemistry and it doesn't go away. Like we always say, you can use a quick fix to solve the problem temporarily but it will recur so long as you don't solve the root problem. Good luck and let us know how it goes.