Over the past 20 years, with the rapid growth of urbanization nationwide (excluding Hong Kong, Macao, and Taiwan, same below) and the large-scale incremental expansion of cities, the operating mileage of urban rail transit (hereinafter referred to as ′urban rail′) has been growing at a high rate. From 2005 to 2024, the urbanization rate of permanent resident population in China increased from 43% to 67%, a growth of 24 percentage points; during the same period, urban rail operating mileage expanded from 545 km to 12,161 km, an increase of approximately 21 times. Along with the drastic expansion of operating network scale, urban rail now faces severe challenges in achieving high-quality and sustainable development.First, low passenger flow intensity: network expansion leads to diminishing marginal returns in terms of passenger flow intensity. Between 2015 and 2024, urban rail operating mileage increased by about 236%, while passenger intensity declined from 12 100 passengers/(km·day) to 6 100 passengers/(km·day), a decrease of 49.6%. For example, when the Guangzhou Metro network was about 250 km in 2015, the overall network passenger intensity reached about 26 000 passengers/(km·day). However, it has since continuously declined, dropping to about 15 100 passengers/(km·day) by 2024.Second, low utilization of line system capacity: the supply and demand mismatch. In 2023, statistics covering 39 cities and 195 high-capacity urban rail lines nationwide showed: only 36 lines (18.46%) had peak-hour maximum cross-section passenger flows greater than or equal to 30 000 passengers/hour; 70 lines (35.90%) had peak-hour maximum cross-section flows less than or equal to 10 000 passengers/hour. The share of lines with peak-hour capacity utilization above 70% was 15.9%, while 40.51% of lines had utilization below 30%.Third, poor financial performance: high-quality and sustainable development affords heavy burden. In 2023, among 40 cities with available data, only 10 cities (25.64%) had fare revenue covering more than 50% of their basic operating costs, while 17 cities (43.59%) had coverage ratios below 30%. Even when including ancillary business revenues, only two cities in China had urban rail operating income sufficient to cover basic operating costs. By comparison, fare revenues for Tokyo Metro as well as urban rail systems in Hong Kong and Taipei generally cover operating costs in full. In New York City, fare revenues covered 77% and 80% of operating costs in 2018 and 2019 (pre-pandemic), respectively. In London, the figure is generally between 60% and 70%.Fourth, insufficient agglomeration advantages around stations: the integration with urban functions is inadequate. The average level of agglomeration around urban rail stations is relatively low, with many stations surrounded by inefficient or even ineffective land use. Especially within the 300-meter core attraction radius of many stations, the density of both population and employment is far too low, leading to poor alignment between the network and functional urban space. Urban development has long been dominated by automobile traffic, with car ownership and usage culture prevailing. The areas around stations often lack refined design; pedestrians, non-motorized vehicles, and motor vehicles interfere with one another, resulting in low circulation efficiency, prominent safety hazards, and difficulties in organizing high-quality urban public space.The Central Urban Work Conference emphasized that promoting high-quality urban development should be the overarching theme, with connotative urban development as the main trajectory, and urban renewal as a key approach. Efforts must be made to advance urban structural optimization, encourage transformation of growth drivers, enhance urban quality, promote green transition, carry forward cultural continuity, and improve governance efficiency. Urbanization in China is shifting from a phase of rapid growth to one of stable development, while urban development is moving from large-scale incremental expansion to a stage primarily focused on enhancing and optimizing existing stock. Correspondingly, the role of urban rail is evolving from leading incremental urban expansion to driving urban stock renewal—an inevitable outcome of meeting the needs of different stages of urban development.High-quality and sustainable development of urban rail is reflected primarily in passenger flow benefits and financial sustainability. Urban rail ridership mainly originates from areas within a certain radius around stations. A reasonable scale of population and employment density in station catchment areas is the fundamental prerequisite for increasing passenger flow, improving network efficiency, boosting fare revenues, and supporting the high-quality and sustainable development of urban rail. According to statistics from the Tokyo metropolitan region, among all rail transit trips, 49.7% originate within the Tokyo metropolitan area, 45.1% from station catchment areas in surrounding suburban regions (core metropolitan areas and designated major cities, as well as near-core suburban areas), while only 5.2% come from other areas.Taking urban renewal as the lever, allocating limited incremental land resources around urban rail stations, and guiding the concentration of urban population, employment, and functions toward existing station areas can increase the scale of population and employment agglomeration around stations. This is a practical choice at the present stage for promoting high-quality and sustainable urban rail development. At the same time, by integrating ′Rail+Community′ development, it is possible to build continuous, convenient, safe, and comfortable integrated transport systems around stations, effectively coordinating urban functions with residents′ travel, thereby further enhancing the competitiveness and passenger appeal of urban rail.In today′s era of high-quality urban development, urban rail should not only serve as an efficient means of transportation, but also as a vital force in leading urban renewal and connotative development. Urban renewal represents the last opportunity to drive the high-quality and sustainable development of urban rail.

Translated by ZHANG Liman