01 Jun Alex Karner/Investigating transportation equity in Santiago
Por Alex Karner / Investigador del cluster Acceso y Movilidad
Understanding how residents from different demographic groups use transportation systems is the first step towards determining whether a particular system can be said to be equitable. Much academic work has looked at transportation equity in cities in the Global North, especially the United States, where state and federal laws require transportation planning agencies to analyze who will be affected by policies, plans, and infrastructure projects. These efforts have often focused on the quality of transit service provided to minority and low-income populations relative to that provided to wealthier commuters. In part because of a lack of a coherent legal framework and because of the comparative ubiquity of public transport, transportation equity in cities in the Global South has received less attention.
This is surprising because, although mode shares and settlement patterns are quite different between the north and south, the underlying drivers of inequity may be similar, meaning that there is an opportunity for solutions in one location to inform the other. Looking specifically at Santiago, the region is fairly monocentric in terms of economic opportunities, with most wealth and employment centered on the comunas located in the northeast, as shown in the figure of median household income by comuna. Several poorer comunas are located within the major ring road that encircles the city. Many US regions are polycentric, with increasingly dispersed and suburbanizing economic opportunities and poorer minority populations concentrated in city centers. In both locales, the spatial separation of workers from jobs creates similar problems for low-income workers. Specifically, workers without access to automobiles must endure relatively long commutes by public transit to reach increasingly distant employment opportunities.
SECTRA recently released the 2012 origin-destination survey for the 45 comunas comprising the Santiago metropolitan region. This dataset offers the perfect opportunity to examine transportation equity in the region. SECTRA conveniently divides Santiago into seven internal sectors that can be used to take a broad look at travel patterns. Of particular interest from an equity perspective are the commute patterns of low-income workers traveling from sector poniente (including many lower-income comunas) to sector oriente (including the wealthiest parts of the region). The survey counts approximately 190,000 one-way work trips originating in sector poniente for workers earning in the bottom 50% (with household incomes less than $520,000 CLP per month). About 45% of those trips are captured internally, meaning that almost half of the low-income employed residents in poniente are able to work there. According to the survey results, about an equal proportion of these trips use walking (25%, mean travel time 16 minutes) and Transantiago (25%, mean travel time 47 minutes). Average travel time for all trips captured internally in sector poniente for all modes is 31 minutes.
The second largest destination for sector poniente’s workers is sector oriente, accounting for 41,000 total (22%) one-way work trips. This particular trip presents unique challenges – its mean travel time is 85 minutes. The vast majority (73%) use either entirely Transantiago or transfer to metro with travel times exceeding 90 minutes.
About 22% of low-wage workers employed in sector oriente are able to live there as well. Their travel behavior offers an important point of comparison. A majority of these commutes is made by walking (54%), taking about 13 minutes. The second most popular mode is Transantiago (27% of trips), followed by bicycling (8%), and auto (8%). There are no variables in the survey that capture the proportion of household income allocated to housing costs, but poorer workers living in oriente are likely trading off substantial travel time savings for an increased housing cost burden.
It is thus a pressing matter of transportation equity to solve the problem of long commutes for low-income workers that far exceed what they would expect if they were able to locate closer to their jobs. Similarly, workers should not have to pay more than they can afford to realize a reasonable commute. It is likely that economic opportunities in Santiago will continue to centralize and move further eastward, outside the reach of a quick public transit trip or bike ride from locations where the low-income workforce can afford to live. This trend means that the problem is likely to get worse without appropriate policy and planning interventions.
Providing improved transit service –shorter headways, less crowding– from west to east is one possible solution. But this is physically limited by capital, right-of-way, and multimodal congestion. Other approaches could focus on affordable housing and economic development to both bring economic opportunities to poorer comunas and provide additional opportunities for low-income workers to live close to their jobs. Although this latter approach is likely to meet with public resistance, the long run public health and quality of life benefits could be substantial as workers would spend less time commuting and more time with their friends and families and on other activities that enrich their lives. Achieving transportation equity, in Santiago and in cities across the United States, thus requires approaches that go beyond traffic operations and infrastructure to address long-standing patterns of residential segregation and exclusion to better match residential opportunities to the needs of the local workforce.