Aluna Channel Bridge-Tunnel

The Aluna Channel Bridge-Tunnel, officially the Aluna Channel Bridge-Tunnel and Causeway System (ACBT), is a 59.4 km crossing over the Aluna Channel between the Cartadanian states of Alexandria and São Ricardo. Connecting the city of New Venceia and Ricardo County, it forms the western portion of the larger Fortuna Expressway and more largely, IH-68, the major east-west interstate of Cartadania, traveling along its northern coastline.

Completed in 2014, the ACBT is the second-most expensive individual federal highway project in the country, preceded only by its sister-system, the Marée Channel Bridge-Tunnel, which adjoins the Fortuna Expressway and connects São Ricardo to Maresia.

Ferry
Before the construction of the Aluna Channel Bridge-Tunnel, a different, historic era prevailed in Cartadania's transportation landscape, marked by the legacy of ferry transport. This intricate web of ferry routes across the Aluna Channel held a distinct place in the minds of travelers, connecting the states of Alexandria and São Ricardo. Two prominent routes provided a lifeline of sorts for residents and visitors alike.

The first of these routes operated between the rapidly growing Port District of New Venceia in Alexandria and the more suburban town of Sanova in São Ricardo. The course it followed was nearly identical to the path currently occupied by the Aluna Channel Bridge-Tunnel, acting as a pivotal connection that now forms the western portion of the Fortuna Expressway.

The second vital route linked the town of Adonis Wharf in Alexandria to the quaint town of Cerasia in São Ricardo. This particular connection served as a vital artery for the transportation of people and goods, fostering interconnectivity and economic exchanges.

This era of ferry travel persisted until 2014 when an ambitious endeavor resulted in the construction of the Aluna Channel Bridge-Tunnel, which ultimately transformed this region's transport dynamics. With the advent of this engineering marvel, the ferry routes were gradually replaced by the efficient and modern bridge-tunnel system. However, these routes still retain their legal status, serving as backup travel options in the event of unforeseen damage or emergencies on the bridge-tunnels.

Planning for fixed crossing
The origins of the Aluna Channel Bridge-Tunnel as a system, as well as the sister system, both marvels of modern transportation when they were constructed, trace back to the emergence of the idea for a fixed crossing over the Aluna Channel. The concept was catalyzed by a complex interplay of factors, prominently driven by the need for a secure and efficient transportation link between the states of Alexandria and São Ricardo that traditional diesel ferries weren't able to reliably and constantly offer.

As discussions unfolded, it became evident that a bridge-tunnel hybrid, accommodating both road and rail traffic, was the optimal solution. This choice was informed by multiple considerations, with key input from the Department of Transportation, the Department of Defense, and Congressional influence. Notably, the Department of Defense and Congress underlined the importance of ensuring the safety of military vessels during transit through the Aluna Channel. This concern was pivotal in steering the project towards a bridge-tunnel configuration.

The multi-modal functionality of the Aluna Channel Bridge-Tunnel, featuring four lanes for vehicular traffic with an expandable capacity of up to eight lanes, alongside dedicated rail tracks, facilitated the seamless movement of both passengers and cargo, contributing significantly to the nation's economic and infrastructural objectives. The rail section, designed for overhead electrification, ensured the versatility of the transport system for both freight and passenger rail services. Additionally, the bridge-tunnel design provided unrestricted overhead clearance for cargo ships, assuaging concerns about limiting vessel height.

The project was under the collective jurisdiction of three prominent agencies: the Alexandria Department of Transportation, the São Ricardo Department of Transportation, and Cartadania's federal Department of Transportation. This triumvirate of oversight entities was instrumental in ensuring that the project adhered to a unified vision while accommodating the specific needs of the individual states and the nation at large.

In the initial stages, the project's development was steered by influential figures, including renowned engineers, transportation experts, and government officials. Their dedication and vision laid the foundation for this extraordinary undertaking. Notably, the dynamic design of the Aluna Channel Bridge-Tunnel was entrusted to Neptune Engineering Group, a Cartadanian firm hailing from the state of Lombardia. Their innovative prowess was essential in shaping the bridge-tunnel hybrid, accommodating both road and rail traffic.

Construction of the project was assigned to the distinguished Pelaxian firm, Burgons and Osfings, celebrated for their engineering acumen and proficiency in executing large-scale infrastructure projects. This collaboration transcended national borders and contributed to the project's international recognition.

The decision to proceed with the bridge-tunnel configuration, rather than a continuous bridge, was grounded in a pragmatic assessment. Concerns surrounding the safety of military vessels during their passage through the Aluna Channel, as well as the imperative to provide unrestricted overhead clearance for cargo ships, played a pivotal role in influencing this choice.