Spatio-temporal variations of traffic congestion under work from home (WFH) arrangements: Lessons learned from COVID-19.

Traffic congestion has been a persistent problem in cities globally. Theoretically, commuting-related congestion can be relieved by promoting working from home (WFH). Amid the COVID-19 pandemic, WFH arrangement has been encouraged or enforced to reduce the spread of the coronavirus. Under these circumstances, it was reported that traffic congestion has been alleviated in many cities. However, changes in congestion patterns within a city have not been studied in-depth. In this study, we analysed the congestion index (CI) at peak hours, when commuting-related congestion is typically most serious, throughout different waves of the pandemic in Hong Kong. Results show that under WFH arrangement, peak-hour congestion has been alleviated. Within a day, morning peak congestion was more relieved. Spatially, significant drops in CI were found not only in the central business district and urban cores but also in some new town areas. This paper has significant implications for urban planners in creating more sustainable cities that duly consider the commuting needs of residents, and cautions against the optimism that WFH can relieve urban transport problems despite jobs-housing imbalance. While the WFH arrangement has potentials to ease commuting congestion, future e-working and transport measures need to take spatial and temporal dimensions into account. • Spatio-temporal dynamics of urban traffic congestion under COVID-19 were captured. • In Hong Kong, work from home had a bigger impact on morning than evening peak. • Morning peak congestion relief was not only limited to the CBD. • The two commuting peaks were identifiable even during work from home periods. • About 25% of planning units had lower peak-hour congestion under the "new normal". [ABSTRACT FROM AUTHOR]