Koontz Lake is a census-designated place in Starke County, Indiana, United States. The population was 1,554 at the 2000 census. It is named for the nearby lake named after the owner of a nearby mill, Samuel Koontz. Koontz Lake apartments for rent comparison page shows most up to date rent information on Koontz Lake apartments and houses. Rent information is obtained from multiple rental sources but we cannot guarantee their accuracy.