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April 29, 2021

Mobility Changes in the Spread of Coronavirus in Dense Urban Environments

By Dr. Peng Chen, Assistant Professor, Urban & Regional Planning

Coronavirus (COVID-19) infections have surged worldwide and this ongoing crisis reminds us of the importance of evaluating its impact on human mobility and understanding the disease diffusion pattern in urban spaces. In the United States, the coronavirus first presented in Seattle, then outbroke in New York City (NYC) at a larger scale with increasingly explosive growth in large cities such as Los Angeles, Miami, and Houston, and eventually spread across the U.S. Most states issued stay-at-home orders in late March 2020 to intervene in the spread of the virus. People’s daily lives have been greatly impacted. Given the financial pressure, many states took a stepwise path to reopen the economy in late May/early June 2020. Despite the related actions ordered to protect people from infection—such as social distancing, wearing face masks in public spaces, and canceling non-essential events—several states soon experienced the sharp increment of positive COVID-19 cases after reopening the economy.

Transit and public bike operations have a profound impact on people’s daily mobility. It is worthy of investigating the joint effect of transit ridership, public bike usage, and responsive policy tools on the coronavirus diffusion. Besides, early studies had attended to the effect of density and sociodemographic factors on the coronavirus infection. In NYC, density and mixed land-use appear to be significant variables for the spread of the disease. Nevertheless, there are high-density and mixed land-use world cities that have effectively mitigated the spread of COVID-19, such as Hong Kong, Singapore, and Tokyo. Urban form factors alone cannot explain the diffusion of coronavirus. Public policy plays an important role in slowing down disease diffusion. After the first case was confirmed back in March 2020, NYC took a series of actions as responses, such as the PAUSE order and multi-step economy reopen.


Figure 1: Modeling framework

This analysis examines the coronavirus diffusion in relation to mobility changes under the joint impact of the external event (coronavirus outbreak) and the internal events (responsive policy tools, such as reduced transit and economy reopen) at a microscopic level, where the effect of socioeconomic factors, medical facilities, and the built environment are controlled for, as shown in Figure 1. The unit of analysis (zip code) is the smallest geographic unit that the city has documented, as shown in Figure 2.


Figure 2: The spatial distribution of positive coronavirus cases in NYC

Transit, Bikeshare, and Telecommuting
This analysis incorporated daily subway ridership and the policy of reduced transit services during the pandemic to model the impact of transit operation on the coronavirus infection. The results suggested that reduced transit services helped prevent disease diffusion, while transit operations facilitated the spread of coronavirus, and such an effect continued over time. The implication of this finding is debatable. To avoid infection, transit must operate cautiously with well-designed preventive strategies and sanitary measures. However, most people from the vulnerable group cannot afford a car in NYC, and transit is the most affordable transportation mode to obtain mobility services for jobs and critical activities. The Metropolitan Transportation Authority (MTA) can only place additional regulations on transit riders—such as wearing face masks, making hand sanitizer available to riders in stations, encouraging riders to travel during less busy times, and creating passenger limits—to avoid overcrowding and support social distancing. The public needs safer and more alternative mobility options.

Public bike use suggested a negative relationship with the number of coronavirus cases. As noted, public bike use was tripled during the three months in 2020. People who are concerned with the risks of riding transit may switch to using public bikes. This result provided support to the expansion of Citi Bike in NYC by adding more stations and bikes.

Areas with a higher percentage of telecommuting suggested a negative association with the number of coronavirus cases. The percentage of individuals working from home increased to 42% during the pandemic. The outbreak of coronavirus provided an opportunity to explore the potential of telecommuting. Working from home has many advantages, such as saving operational costs and rent, reducing travel time, mitigating road congestion during peak hours, and giving individuals the freedom to manage their schedules. If employees can maintain the same level of work performance, companies are encouraged to keep telecommuting as an option.

Is the built environment guilty?
This analysis partially confirmed the second hypothesis that coronavirus is more likely to diffuse in a dense urban environment. Population, residential areas, and the sum length of streets—which represent measures of density and connectivity—showed positive effects on coronavirus cases. The other built environmental factors were insignificant. Human activity concentration was greatly reduced at workplaces and public spaces during the pandemic, possibly due to the stay-at-home orders. Mixed land-use showed no significant effect on coronavirus cases. In contrast, people may feel safe in their neighborhoods, and consequently, they may not keep the same level of preventive awareness when they walk and ride bikes on streets near their homes. Additionally, even if people are infected in another place, the location where they were initially infected is mostly unknown, and their records will simply mark their home zip code as the infection site. Alternatively, infected individuals that lack identifiable travel history or exposure signals contribute to community transmission. The way of reporting brings difficulties to tracking the disease diffusion pattern and this misleads scholars and practitioners to consider some neighborhoods as more risky environments.

According to the modeling result, a high-density urban environment like NYC was not resistant to disease diffusion. The performance of NYC in this pandemic informed us to have additional reflections on conventional urban planning thoughts. A dense neighborhood with mixed land-use and connected streets is what planning scholars have advocated for decades. All good features seem to be the conditions for disease diffusion, and suddenly makes them undesirable planning principles. Yet, is density a core determinant for disease spread? Cities like Los Angeles, Miami, and Houston are all low-density cities where the coronavirus wave is explosively rising. In comparison, in high-density Asian cities like Singapore, Hong Kong, and Tokyo the coronavirus is much controlled. Therefore, density is only a sufficient condition, but not a necessary condition for disease diffusion. The core determinant of coronavirus diffusion is face-to-face contact without adequate protection.

A recent study argued that people may favor isolated neighborhoods, sprawled urban form, and decentralization post-pandemic without providing solid evidence to support such claims. Another claim is that "rural is not the answer." Residential mobility is a complicated decision outcome and the reasons are greatly varied by individuals. Most people relocate for job placements, promotions, retirement, affordability, school quality, and life course events such as marriage, divorce, and the birth of children, etc. Panic may only exist for a short period of time and coronavirus can hardly be a cogent reason for mass relocation. For more affordable housing opportunities and a better quality of life, given the increased popularity of telecommuting, there are many other stronger reasons for relocation. However, it is not reasonable to place excessive criticisms on conventional planning thoughts and discourage compact development.

Planners lead public processes and effect social change, in addition to envisioning the future of a city/community. When facing possible harm to the public, planners in local agencies should collaborate with other departments, bringing the risks of each policy tool to the table and negotiating with related stakeholders to sort out the best solutions. No generalizable rule can be applied to all settings. Planners in local agencies should engage people and present the needs of senior citizens, low-income, and people of color to the public.

Examining the relationship between the built environment, mobility changes, and highly infectious diseases contributes to the development of safer and cleaner cities. Individual-level data with contact tracing is desired for improving the accuracy of analytical results and informed decision-making from a behavioral perspective. The U.S. Census is implementing a three-phase Pulse Survey. More microscopic data is expected, which can facilitate the examination of the disease diffusion pattern at a finer spatial granularity. Qualitative research is highly encouraged to better understand the needs of people from the vulnerable group, gain knowledge from an individual level, and provide additional insights into the process of the coronavirus infection.

With lessons learned from NYC, decision-making is challenging during the pandemic, and each decision presents a comprised solution by weighing benefits against costs. Solutions can greatly vary by case. There are rooted political, financial, cultural, and physical differences across different cities and states. Planners should actively participate in the decision-making process, engage people online, collaborate with all related departments, and reach reasonable solutions with adequate considerations on all aspects in the local environments.


April 20, 2021

Fiscal Impacts of COVID-19 Mitigation Policies: Why the American Rescue Plan Act is a Major Relief for U.S. Local Governments

By Dr. Stephen Aikins, Associate Professor & Program Director, Public Administration

The COVID-19 mitigation measures put in place by state and local governments resulted in severe revenue shortfalls for many county and municipal governments, forcing them to take measures aimed at operational efficiency and cost savings. This stems from the fact that COVID-19 caused the steepest decline in economic output and unemployment in the United States since World War II. In March 2021, President Biden signed into law the $1.9 trillion American Rescue Plan Act that includes $350 billion in aid for state and local governments, many of whom have been stretched to their limits by the pandemic. Of this amount, $120 billion was earmarked for county and city governments – a much welcomed relief due to the financial impacts of COVID-19.

The policy responses to the pandemic also made clearer the political divide in America and how such a divide manifested in policy actions initiated by various local jurisdictions across the United States. In a nation-wide survey conducted by this researcher in Fall 2020—and reported in March 2021—49 percent of the respondents said their local governments mandated face masks, while 49 percent said their local governments only recommended it. This finding is reminiscent of the political debate in the U.S. that has characterized the use of face masks since the onset of the pandemic. The survey results also show that while local jurisdictions were evenly split on face mask mandates and recommendations, 65 percent of them recommended citizens stay at home unless it was necessary to go out, and the same percentage recommended self-isolation after exposure. Additionally, 68 percent of jurisdictions recommended citizens avoid crowded places, while 65 percent of them recommended self-isolation after exposure to COVID-19, compared to the 34 percent of jurisdictions that mandated self-isolation.

The COVID-19 mitigation policies implemented by local governments—such as lockdowns and sheltering in place, closure of nonessential businesses, school districts, colleges, and universities, and restrictions on public gatherings—were of varying durations across jurisdictions. While 22 percent of jurisdictions closed nonessential businesses for 16 to 30 days—between March 1, 2020 through June 30, 2020—31 percent of them had the policy in place for 31 to 45 days, and 23 percent closed those businesses for 46 to 60 days. Twenty five percent allowed restaurants to remain open for delivery only for 16 to 30 days, while 29 percent and 25 percent implemented that policy for 31 to 45 days and 46 to 60 days, respectively.

The link to the online survey was sent to a stratified random sample of 1,000 local government officials in the U.S. and 245 of them completed the survey, representing a 25 percent response rate. Forty-eight of the respondents are in the Northeast region of the U.S., 51 are in the Southeast, 50 are in the Midwest, 43 are in the Southwest, and 53 are in the West. This distribution implies that respondents were evenly spread in all five regions of the United States. Jurisdictions of all sizes were also represented in the survey.

Analysis of the survey responses shows that the COVID-19 mitigation policies have had some impact on the FY 2020 budget revenue of county and city governments, including declines in sales tax revenue and personal income tax revenue.

The decline in consumption and spending on services and durable goods stemming from the COVID-19 mitigation policies implemented by state and local jurisdictions has put many of these jurisdictions in difficult financial positions. The following illustrates some of the revenue shortfalls, the actions taken by local governments, and why the $120 billion aid is a welcome relief for county and city governments:

Budget Revenue Loss in FY 2020: Figure 1 shows that the governments of 74 of the 245 survey respondents (30 percent) had an estimated budget revenue loss of less than 5 percent in FY 2020 as a result of COVID-19, 68 respondents (28 percent) had between a 5 and 9 percent revenue loss, 52 respondents (21 percent) had a revenue loss between 10 and 14 percent, and 20 respondents (8 percent) had a revenue loss between 15 and 19 percent. This implies that 87 percent of the respondents had up to a 19 percent budget revenue loss due to the impacts of the COVID-19 pandemic.


Sales Tax Revenue Loss in FY 2020: Figure 2 shows that 57 of the 245 survey respondents (23 percent) said their governments had an estimated revenue loss of less than 5 percent in their FY 2020 sales tax revenue, 66 respondents (27 percent) had between a 5 and 9 percent sales tax revenue loss, and 30 respondents (12 percent) had between a 10 and 14 percent revenue loss. This shows that 50 percent of the local jurisdictions had up to a 9 percent revenue loss in sales tax due to the COVID-19 pandemic.


Income Tax Revenue Loss in FY 2020: Figure 3 shows that 61 of the 245 survey respondents (25 percent) said COVID-19 had no effect on their FY 2020 income tax revenue. Forty-five respondents (18 percent) said their governments had an estimated revenue loss of less than 5 percent, 71 respondents (29 percent) said they had an estimated revenue loss between 5 and 9 percent, and 13 respondents (5 percent) experienced a revenue loss between 10 and 14 percent. This implies that 52 percent of respondents said they had up to a 14 percent revenue loss in income tax due to the COVID-19 pandemic. Thirty-six respondents (15 percent) said that income taxes are not applicable in their state.


In response to the revenue shortfalls, various local governments have adopted measures to deal with such impacts. The measures include reducing funding and FTEs for various administrative services in FY 2020 and planned reductions in FY 2021. Forty nine percent of respondents said their governments reduced funding for police in FY 2020 and 42 percent said their governments did the same for fire, healthcare, and mass transit services. Additionally, governments have performed various other actions aimed at expenditure reductions and efficiency of operations, including reviewing programs to eliminate waste, postponing certain expenditures, and scrutinizing operations for savings.

The findings from the survey show that—the above-mentioned responses notwithstanding—local governments need more financial help from the federal and state governments. Twenty two percent of local jurisdictions anticipate between 5 and 9 percent of their FY 2021 total budget revenue to come from the federal government, compared to the 15 percent who actually received between 5 and 9 percent of their total revenue from the federal government in FY 2020. The percentage of local governments who anticipate between 5 and 9 percent of their total budget revenue from the state government in FY 2021 has also risen to 22 percent, from the 14 percent of jurisdictions who actually received between 5 and 9 percent of their total revenue from the state government in FY 2020. The percentage of jurisdictions who anticipate less than 5 percent of their FY 2021 revenue from state governments has also increased to 71 percent, compared to the 46 percent who actually received such help in FY 2020.

It is important to note that the fiscal distress on local governments is exacerbated by the fact that county and city governments had to carry a higher financial burden in dealing with the public health crisis, as they struggled to provide support for their vulnerable citizens at the time when their own-source revenue plummeted. As a result of the revenue shortfalls, many local governments cut funding for administrative services such as fire, police, public housing, healthcare, education, and mass transit. According to the federal Bureau of Labor Statistics, about 1.4 million state and local government workers—many of them employed by schools—have lost their jobs since the beginning of the pandemic.

Unlike the $150 billion state and local government aid provided under the CARES Act that was signed into law in March 2020—which provided direct aid to counties and cities with a population of at least 500,000 and could only be used as a response to the pandemic—the amount provided under the American Rescue Plan Act is meant to help alleviate the COVID-19 imposed financial stress on all county and city governments. Consequently, the $120 billion federal aid to local governments provided under this act will not only replenish the lost revenue mentioned above, but it can also help to restore local services that were cut and the rehiring of essential public workers who were laid off as a result of the pandemic.

View the full survey results here.