A diagram illustrating the concept of a layered road. [Seoul Metropolitan Government]
A diagram illustrating the concept of a layered road. [Seoul Metropolitan Government]

The Seoul Metropolitan Government has established new criteria to allow more flexible use of land that has long been difficult to develop because of roads running through it, including the conversion of space beneath roads into parking facilities.

The city announced Monday it will implement the "criteria for three-dimensional designation of urban planning facilities (roads)," aimed at making more efficient use of limited land resources and expanding transportation infrastructure.

Seoul has long pursued policies to combine urban planning facilities such as roads and parks with other uses through layered and mixed-use development. However, roads have been subject to stricter limits on such arrangements, given the need to preserve their public function and allow for future expansion.

The city said it drew up the new criteria in response to growing demand for three-dimensional use of road space within the city. The core of the framework is to spell out consistent planning standards and safety-based scale requirements so that roads retain their primary function and avoid maintenance problems when used in a layered configuration.

A layered road designates only a portion of the vertical space occupied by a road as an urban planning facility, rather than the entire column of space. Transportation infrastructure such as roads can be built above private land, while the space below can be used for parking and similar purposes, allowing public and private parties to share a single parcel of land.

Eligibility is limited to three situations: cases where a road has divided a plot of land, leaving a remainder too small for efficient use; cases where large-scale development creates a need for additional connecting roads between surrounding areas; and cases where improvements to the pedestrian environment are deemed necessary.

The road's spatial dimensions must cover the full above-ground portion and secure at least 3 meters below the surface. The city also plans to make information on three-dimensionally designated roads publicly accessible through land-use confirmation documents. The guidelines are designed to minimize confusion in private-sector projects and improve administrative predictability by incorporating the concept and standards for layered roads, while taking into account both the public nature of roads and housing supply.

The city said it expects the new standards to give private landowners more efficient use of their land while enabling the public sector to build a seamless transportation network, ultimately increasing the flexibility of urban space.

In addition, Seoul said it will actively support the application of the new system in major urban renewal projects — including its fast-track integrated planning and Moa Town initiatives — to accelerate housing supply and other project goals.

Kim Chang-gyu, head of the Seoul Metropolitan Government's Urban Space Bureau, said the move "will serve as a turning point for using Seoul's urban space in a flexible and innovative way, going beyond simply dividing road space."


ikson@heraldcorp.com