Trenk Reservoir   Be the first to submit input for Trenk Reservoir. If you have info on Trenk Reservoir, Carter County, Montana please submit it here to improve this web site.          These outdoors activities are available near Trenk Reservoir.   Public Lands Near Trenk Reservoir: Medicine Rocks State Park, Montana, 24 miles away Devils Tower National Monument, Devils Tower - WY, 53 miles away   Ski Areas Near Trenk Reservoir: Terry Peak, South Dakota, 91 miles away       1100 foot drop, 6 lifts, 24 runs