In preparation for the opening of the Hokkaido Shinkansen, the Seikan Tunnel and associated approaches were converted to dual gauge, with both the Shinkansen standard and narrow gauge tracks. Upon the opening of the Shinkansen line the section of the conventional Esashi Line approximately paralleling the same route between and was transferred from the control of JR Hokkaido to a newly established third-sector railway operating company, South Hokkaido Railway Company, becoming the Isaribi Line.
Operations
Service types
Two train service types operate on the Hokkaido Shinkansen: limited-stop Hayabusa services between Tokyo or Sendai and Shin-Hakodate-Hokuto, and semi-fast Hayate services between Morioka or Shin-Aomori and Shin-Hakodate-Hokuto. Under the initial timetable, ten return Hayabusa services operate daily between Tokyo and Shin-Hakodate-Hokuto and one return service operates daily between Sendai and Shin-Hakodate-Hokuto. One return Hayate service operates daily between Morioka and Shin-Hakodate-Hokuto, and one return service daily operates between Shin-Aomori and Shin-Hakodate-Hokuto.
Operating speed
Initially the maximum speed on the approximately dual-gauge section was. There are approximately 50 freight trains utilising the dual-gauge section each day, so limiting the travel of such trains to times outside of Shinkansen services is not an option. Because of this and other weather-related factors cited by JR East and JR Hokkaido, the fastest journey time between Tokyo and Shin-Hakodate-Hokuto was 4 hours, 2 minutes. The new section took 61 minutes from Shin-Aomori to Shin-Hakodate-Hokuto on the fastest services. By 2018, it was proposed to allow one Shinkansen service each day to travel at by ensuring no freight trains are scheduled to travel on the dual-gauge section at that time. To achieve the full benefit of Shinkansen trains travelling on the dual-gauge section at, other alternatives are being considered, such as a system to automatically slow Shinkansen trains down to when passing narrow-gauge trains, and loading freight trains onto special "Train on Train" standard-gauge trains built to withstand the shock wave of oncoming Shinkansen trains traveling at full speed. This would enable a travel time from Tokyo to Shin-Hakodate-Hokuto of 3 hours and 45 minutes. The tunnel speed limit was raised to in March 2019, saving 4 minutes on the Shin-Aomori to Shin-Hakodate trip. In March 2019, JR Hokkaido announced that it had requested permission from the MLIT to increase the speed limit on the line to. If approved, it intends for the entire line to be outfitted for the new top speed by the time the full line opens in 2030, except for the dual-gauge section.
Stations
Rolling stock
All services are formed of 10-car JR East E5 or JR Hokkaido H5 series trainsets. In February 2014, JR Hokkaido placed an order for four 10-car H5 Series Shinkansen trainsets for use on Hokkaido Shinkansen services from March 2016. Based on the E5 series trainsets operated by JR East since 2011, the order for 40 vehicles cost approximately 18 billion yen. The first two sets of the order are scheduled to be delivered to Hakodate Depot by road from Hakodate Port in October 2014, with test running commencing before the end of the year. The remaining two sets on order are scheduled to be delivered in 2015. The vehicles feature the usual upper green and lower white livery, with a purple stripe in the middle. The color purple was chosen to represent the purple flowers of Hokkaido: lilacs, lupine and lavender. Inside, the ordinary-class cars feature wood paneling and carpet with a snowflake motif. Green class features cream-colored walls representing the local dairy industry and carpet with a drift-ice motif. Gran class features dark blue carpets, said to be modeled after the shimmering lakes and bodies of water along the route.
History
In the early 1970s, two other Shinkansen routes were proposed for Hokkaido: Sapporo - Asahikawa and Oshamambe - Muroran – Sapporo. There were also further unofficial plans to connect to Abashiri, Kushiro, and Nayoro/Wakkanai. These plans have been indefinitely shelved. On 1 November 2014, a ceremony was held at Kikonai Station to mark the completion of track-laying for the line between Shin-Aomori and Shin-Hakodate-Hokuto. Test-running on the Hokkaido Shinkansen tracks within Hokkaido commenced from 1 December 2014, initially at low speeds, with the speed raised to the maximum of later that month. Test-running was extended through the Seikan Tunnel to Oku-Tsugaru-Imabetsu in December 2014. Test-running south of Oku-Tsugaru-Imabetsu commenced on 21 April 2015, with the first train reaching Shin-Aomori Station from the north in the early hours of 24 May.
Future plans
JR Hokkaido is extending the Hokkaido Shinkansen from Shin-Hakodate-Hokuto to, planned to open by 2030. Tunneling work on the Murayama tunnel, situated about north of Shin-Hakodate-Hokuto station commenced in March 2015, and is scheduled to be completed by March 2021. The extension will be approximately 76% in tunnels, including major tunnels such as Oshima, Teine and Shiribeshi. When the section to Sapporo opens, the estimated journey time from Tokyo to Sapporo will be at most 5 hours and 1 minute, but the goal is for it to be below 4 hours.
