ringing the first barrels of North Slope crude oil to market in the ‘70s required the construction of not one but two economic lifelines. The flashiest, glinting where sunlight reflects from its steel curves, is the Trans Alaska Pipeline System (TAPS). But building TAPS and the facilities to bring oil to the surface at Prudhoe Bay required 414 miles of cross-country road first.

Construction of the haul road began in 1969, but delays in TAPS construction meant that work didn’t resume until 1974. The remaining 390 miles of road were completed in a five-month flurry. Pipeline construction soon followed, and the activity of truckers hauling equipment up the road was nearly constant. Teamsters reportedly could make between $7,000 and $10,000 per month (between $40,000 and $65,000 today) if they were willing to brave the nascent road’s dangerous conditions.

After five years, Alyeska Pipeline Service Company transferred ownership of the haul road to the State of Alaska, and it was named for North Slope oil prospector James W. Dalton. It remained an industry-only road until 1981, when the public was allowed to drive from its junction with the Elliott Highway near Livengood, north of Fairbanks, as far as milepost 211 north of Wiseman. Not until 1994 was the entire length of the Dalton Highway opened to the public, and even today it’s not a trip undertaken lightly.

“The road continues to be challenging,” says John Perrault, spokesman for the Alaska Department of Transportation and Public Facilities (DOT&PF) Northern Region. “But not nearly to the extent it was in 1974.”

While the road is challenging, it is also an essential part of what became the best solution for moving North Slope oil. Even amidst the excitement of discovering oil in the ‘60s, developers were faced with the conundrum of getting the product to market. Several solutions—in varying degrees of expense and feasibility—were proposed, including a fleet of colossal twelve-engine aircraft from Boeing, to be nicknamed the “Flying Pipelines”; an extension of the Alaska Railroad; and a line of submarine oil tankers, envisioned gliding beneath the Arctic ice cap. An ice-breaking tanker, SS Manhattan, was tested in 1969 but deemed too risky.

Even as SS Manhattan made its journey through the Northwest Passage, an overland pipeline was selected as a safer and more efficient solution.

Today, TAPS and the Dalton Highway remain in a kind of industrial symbiosis. In most places along the haul road, this relationship is plainly evident as the pipeline wiggles just a stone’s throw from the roadway.

According to Alyeska Pipeline Service Company, an average of 470,000 barrels of oil flowed through the pipeline daily in the summer months of 2024. Volume is down from a bit more than half a million barrels per day in 2019, and the peak of 2 million barrels per day in 1988 is a distant memory.

However, the flow along the haul road, northward and southward, is increasing. DOT&PF reports that the Milepost 339 traffic monitoring station counted average annual daily traffic of 210 in 2023. This station, located on the north side of the Brooks Range, saw average annual daily traffic of 120 in 2022 and just 80 in 2021. Freight transportation companies like Alaska West Express, Lynden, Carlile Transportation, 49th Freight, Span Alaska Transportation, Black Gold Express, and others regularly run the road.

Truckers endure drastically changing conditions depending on the season. Springtime features rapid snow melt and ground thawing, and breakup season ushers in a summer of potholes and mud. Fall brings colder weather, and by winter, blowing snow and ice are the orders of the day. Freight trucks are equipped with tire chains (sometimes used as frequently in the mud of summer as they are the frost of winter), road flares, spare tires and fluids, and spill containment kits, while drivers carry extra food and winter gear.

Much of the Dalton’s increased traffic is due to larger numbers of tourist travelers, as well, according to Perrault. The Dalton remains one of just two highways in North America that dip a toe in the Arctic Ocean, although driving through Prudhoe Bay oil fields to Oliktok Point is restricted. The other highway, an extension of the Dempster Highway in Yukon Territory to Tuktoyaktuk in the Mackenzie River delta, was completed in 2017.

Motorists looking for the ultimate getaway can spot wildlife roaming along the Dalton Highway corridor, including musk oxen, wolves, peregrine falcons, and more. One of the state’s most accessible caribou populations, the Porcupine Herd, makes its way across the North Slope each summer and fall, so the highway draws appreciable numbers of hunters, as well.

Dalton Highway maintenance requires DOT&PF to track a moving target. DOT&PF has an annual budget of $16.5 million to maintain the Dalton Highway: $10.5 million comes from state funding and the remaining $6 million is federally funded. The goal is to keep the road safe and passable, thereby supplying the key North Slope fields with requisite equipment and support.

Mitigation efforts must adapt to meet these seasonal needs. Daily maintenance activities for DOT&PF include filling potholes, road grading and/or snow plowing, and weather monitoring. These occur along the entirety of the highway’s length.

However, there are also notoriously difficult parts of the highway that require constant vigilance. Commonly known as the crux of the Dalton Highway, Atigun Pass has a steep grade, and in winter months is prone to extreme wind, snowfall, and avalanche danger. One of DOT&PF’s primary concerns is making the tough call to close the road if conditions warrant, according to Perrault. DOT&PF maintains a remote weather monitoring station in Atigun Pass to keep tabs on these conditions, and one of the department’s long-term objectives is to install a second monitoring station.

North of Atigun Pass, from Milepost 362 to 414, whiteout conditions can make the road impossible to see. In 2019, for this stretch of the highway, a project installed and tested road delineators—sturdy, vertical markers planted on either side of the road to mark its edges—which are a common antidote. Embankment construction is another key long-term strategy for managing thawing permafrost and ensuring the road is strong enough to handle heavy traffic.

The department is also exploring the use of thermosyphons to maintain the roadbed. More than 100,000 of these innovative devices are incorporated into TAPS to keep permafrost beneath its pylons frozen. The two-phase closed thermosyphons are vertical, sealed pipes that use evaporation and condensation to maintain ground temperatures and prevent thaw settlement. The technology can be effectively adapted for road use—the only kicker, says Perrault, is their expense.

Several projects are underway at varying stages along the highway to improve its functionality and safety, such as the reconstruction of bridges, the installation of guardrails, and culvert replacement. In total, DOT&PF has invested $160 million in Dalton Highway maintenance north of Atigun Pass in the last five years alone. Estimates put investments over the next half-decade at $175 million for the entire Dalton corridor.

For regular maintenance and major construction, crews are housed at any one of seven DOT&PF maintenance stations along the Dalton Highway. Each maintenance camp ideally consists of two to four workers and is expected to cover between 60 and 70 miles of road. The remoteness of this duty makes the jobs hard to fill, however. In 2023, DOT&PF saw an additional $8 million in its budget to address staffing shortages, particularly along the Dalton’s problem areas.

The 50th anniversary of the Dalton Highway is even more impressive considering what might have been but never was. During Wally Hickel’s first term as governor, the state mapped a road corridor via Anaktuvuk Pass and undertook construction in the winter of 1968. Hickel boasted that he drove the tractor for the first six miles himself and then ordered his crew keep going until they hit Prudhoe Bay.

Hickel’s gateway to the Arctic was completed in March 1969.However, the Hickel Highway soon failed due to poor engineering and intense permafrost thawing. The state discontinued maintenance and abandoned the road by April—the following month. Its alignment, situated to the west of where TAPS and the Dalton Highway exist today, remains a bare scratch on the landscape.

It is a testament to the dedication and quality of Alaska’s engineers and contractors that the Dalton remains today.

Fifty years ago, it was unimaginable that the Dalton Highway would be opened to the public. That happened, of course, in 1994. Fifty years ago, it was downright absurd to think that sections of the road would be paved. As of now, more than 100 miles are asphalt. All improvements, past and future, to the Dalton highway share one thing.

As Perrault says, “Determination is the main ingredient.”