National Highways Network
The National Highway System (NHS) is a pivotal framework of strategic highways in the United States, encompassing the extensive Interstate Highway System and the United States Numbered Highway System. This network also integrates various roads serving key transportation and strategic facilities such as airports, ports, military bases, and railway stations.
Components of the National Highway System
The NHS was established under the auspices of the Intermodal Surface Transportation Efficiency Act (ISTEA) in 1991. This act was instrumental in laying down the foundation of a unified, interconnected transportation framework. This system aims to reduce energy consumption and air pollution, thereby promoting economic development and bolstering the nation's position in international commerce.
Interstate Highway System
The Interstate Highway System, also known as the Dwight D. Eisenhower National System of Interstate and Defense Highways, is a core component of the NHS but retains its independent identity. It plays a crucial role in facilitating defense and mobility across the nation.
Other Principal Arterials
These are highways in both rural and urban areas that provide critical access between an arterial road and major intermodal transportation facilities such as ports and airports.
Strategic Importance
The NHS, although comprising just 4% of the nation's roads, carries a staggering 40% of all highway traffic, 75% of heavy truck traffic, and 90% of tourist traffic. This underscores its vital role in supporting the economy and defense.
Major Strategic Highway Network Connectors
These highways facilitate connectivity between major military installations and routes known as STRAHNET, the Strategic Highway Network.
Intermodal Connectors
These routes provide essential links between major intermodal facilities and the various subsystems that make up the NHS.
Development and Funding
The NHS's development and expansion are supported by strategic funding measures. For instance, Ohio was the first state to leverage a state infrastructure bank to expedite road construction projects. However, challenges such as state law restrictions and project appropriateness sometimes complicate this process.
The act that designated the NHS also restored $5.4 billion in federal funding to state highway departments, enhancing the ability to prioritize crucial projects. Moreover, it repealed federal speed limit controls and prohibited the federal government from mandating the use of federal-aid highway funds for converting existing signs to metric units or purchasing new metric signs.