Loveland Pass

Loveland Pass carries US-6 over the Continental Divide in Colorado at 11,992 feet (CDOT), the highest pass in the state that stays open through the winter. It sits about 800 feet above the Eisenhower-Johnson Memorial Tunnel that takes I-70 under the divide, and it is the road placarded hazmat loads must take whenever it is open (2 CCR 601-8). When the pass is closed, most placarded classes go through the tunnel under CDOT escort, and a short list of classes is barred at all times. Over-height rigs taller than the tunnel's 13 feet 11 inches detour over the top too.

This is a two-lane mountain road with grades of up to 6 percent (CDOT) and a stack of tight hairpin switchbacks on both sides of the summit. There is little margin and not much guardrail. The Colorado State Patrol describes it as self-policing: trucks crawl up and drivers slow way down, which is part of the point of sending placarded loads over an open road instead of through a confined tunnel. The reason behind the ban is fire. CDOT's analysis found a gasoline fire could put out about 100 megawatts of heat, while the tunnel is built for 20.

• Summit 11,992 ft on US-6 (CDOT), the highest Colorado pass kept open all winter
• The required route for placarded hazmat loads whenever the pass is open; when it closes, most classes are escorted through the Eisenhower-Johnson Tunnel (2 CCR 601-8)
• Grades up to 6 percent (CDOT) with hairpin switchbacks on both sides; about 830 ft higher than the tunnel
• Commercial vehicles of 16,001 lb or more must carry chains on I-70 west of Morrison (MP 259), Sep 1 to May 31 (C.R.S. 42-4-106(5)(a)(I)(C))

Colorado's commercial must-carry rule covers the I-70 corridor that feeds the pass. Every commercial vehicle of 16,001 pounds or more on I-70 west of Morrison at milepost 259 has to carry chains or an approved traction device from September 1 through May 31, and getting caught without them costs a commercial driver $500 plus a $78 surcharge (C.R.S. 42-4-106(5)(a)(III)). US-6 over the summit is not one of the listed carry corridors, but CDOT can post the chain law on it. When CDOT and the State Patrol activate the Code 18 chain law in a storm, anything rated 16,001 pounds or more has to put chains on at least four drive tires before going on. The formal chain stations sit on the I-70 approach, at Herman Gulch, Bakerville, and Georgetown, with the Dillon chain station and brake-check on the west side. US-6 over the summit is a two-lane state highway without that network, so chain up before you start the climb. The pass closes case by case for avalanche control, whiteouts, wrecks, and slides, and because it is higher and more exposed than the tunnel, it usually closes first. When it does, CDOT escorts the hazmat loads through the tunnel in a convoy at the top of each hour and holds the rest of I-70 while they pass.

The pass takes its name from William Loveland, president of the Colorado Central Railroad, and the first usable trail over it was finished in 1879. Crews paved the modern road in 1949 and 1950, decades before the tunnel opened beneath it.

When the Eisenhower-Johnson Memorial Tunnel carried I-70 under the divide, it cut 9.1 miles off the US-6 route, but it left hazmat carriers, over-height trucks, bicycles, and pedestrians up top, and they still climb the pass today. The mountains here are not forgiving. An avalanche near the pass on April 20, 2013 killed five backcountry snowboarders, the deadliest in Colorado since 1962.