Half Distance Triathlon Boise: A 70.3-Mile Adventure Swim: Lucky Peak Reservoir (1.2 Miles) Start with a 1.2-mile swim in the clear waters of Lucky Peak Reservoir, beginning and ending at Barclay Bay. With an average water temperature of 72°F (22°C), it's the perfect start to your race. Transition 1 (T1) is located at Barclay Bay Parking Area. Bike: Rolling 56 Miles through Rural Boise After an exhilarating downhill from Lucky Peak, tackle the 56-mile bike course through rural Boise roads and ...