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Ecommerce and Environmental Justice in Metro Seattle

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Publication: Research in Transportation Economics
Volume: 103
Publication Date: 2023

Urban distribution centers (UDCs) are opening at unprecedented rates to meet rising home delivery demand. The trend has raised concerns over the equity and environmental justice implications of ecommerce’s negative externalities. However, little research exists connecting UDC location to the concentration of urban freight-derived air pollution among marginalized populations.

Using spatial data of Amazon UDCs in metropolitan Seattle, this study quantifies the socio-spatial distribution of home delivery-related commercial vehicle kilometers traveled (VKT), corresponding air pollution, and explanatory factors. Results reveal that racial and income factors are relevant to criteria air pollutant exposure caused by home deliveries, due to tracts with majority people of color being closer in proximity to UDCs and highways. Tracts with majority people of color face the highest median concentration of delivery vehicle activity and emissions despite ordering less packages than white populations. While both cargo van and heavy-duty truck emissions disproportionately affect people of color, the socio-spatial distribution of truck emissions shows higher sensitivity to fluctuations in utilization.

Prioritizing environmental mitigation of freight activity further up the urban distribution chain in proximity to UDCs, therefore, would have an outsized impact in minimizing disparities in ecommerce’s negative externalities.

Recommended Citation:
Fried, T., Verma, R., & Goodchild, A. (2024). Ecommerce and Environmental Justice in Metro Seattle. Research in Transportation Economics, 103, 101382.

How Many Amazon Packages Get Delivered Each Year?

Publication: The Conversation
Publication Date: 2022

How many Amazon packages get delivered each year? – Aya K., age 9, Illinois

It’s incredibly convenient to buy something online, right from your computer or phone. Whether it’s a high-end telescope or a resupply of toothpaste, the goods appear right at your doorstep. This kind of shopping is called “e-commerce” and it’s becoming more popular each year. In the U.S., it has grown from a mere 7% of retail purchases in 2012 to 19.6% of retail and $791.7 billion in sales in 2020.

Amazon’s growing reach
For Amazon, the biggest player in e-commerce, this means delivering lots of packages.

In 2021 Amazon shipped an estimated 7.7 billion packages globally, based on its nearly $470 billion in sales.

In 2021 Amazon shipped an estimated 7.7 billion packages globally.

If each of these packages were a 1-foot square box and they were stacked on top of one another, the pile would be six times higher than the distance from the Earth to the Moon. Laid end to end, they would wrap around the Earth 62 times.

Back in the early 2010s, most things bought from were shipped using a third-party carrier like FedEx or UPS. In 2014, however, Amazon began delivering packages itself with a service called “Fulfilled by Amazon.” That’s when those signature blue delivery vans started appearing on local streets.

Since then, Amazon’s logistics arm has grown from relying entirely on other carriers to shipping 22% of all packages in the U.S. in 2021. This is greater than FedEx’s 19% market share and within striking distance of UPS’s 24%. Amazon’s multichannel fulfillment service allows other websites to use its warehousing and shipping services. So your order from Etsy or eBay could also be packed and shipped by Amazon.

The supply chain
To handle that many packages, shipping companies need an extensive network of manufacturers, vehicles and warehouses that can coordinate together. This is called the supply chain. If you’ve ever used a tracking number to follow a package, you’ve seen it in action.

People who make decisions about where to send vehicles and how to route packages are constantly trying to keep costs down while still getting packages to customers on time. The supply chain can do this very effectively, but it also has downsides.

More delivery vehicles on the road produce more greenhouse gas emissions that contribute to climate change, along with pollutants like nitrogen oxides and particulate matter that are hazardous to breathe. Traffic congestion is also a major concern in cities as delivery drivers try to find parking on busy streets.

Urban freight solutions
Are there ways to balance the increasing number of deliveries while making freight safe, sustainable and fast? At the University of Washington’s Urban Freight Lab, we work with companies like Amazon and UPS and others in the shipping, transportation and real estate sectors to answer questions like this. Here are some solutions for what we and our colleagues call the “last mile” – the last leg of a package’s long journey to your doorstep.

  • Electrification: Transitioning from gasoline and diesel vehicles to fleets of electric or other zero-emission vehicles reduces pollution from delivery trucks. Tax credits and local policies, such as creating so-called green loading zones and zero-emission zones for clean vehicles, create incentives for companies to make the switch.
  • Common carrier lockers: Buildings can install lockers at central locations, such as busy transit stops, so that drivers can drop off packages without going all the way to your doorstep. When you’re ready to pick up your items, you just stop by at a time that’s convenient for you. This reduces both delivery truck mileage and the risk of packages being stolen off of porches.
  • Cargo bicycles: Companies can take the delivery truck out of the equation and use electric cargo bicycles to drop off smaller packages. In addition to being zero-emission, cargo bicycles are relatively inexpensive and easy to park, and they provide a healthier alternative for delivery workers.

To learn more about supply chains and delivery logistics, check with your town or city’s transportation department to see if they are testing or already have goods delivery programs or policies, like those in New York and Seattle. And the next time you order something for delivery, consider your options for receiving it, such as walking or biking to a package locker or pickup point, or consolidating your items into a single delivery.

Package delivery can be both convenient and sustainable if companies keep evolving their supply chains, and everyone thinks about how they want delivery to work in their neighborhoods.

Recommended Citation:
Goodchild, A. How many Amazon packages get delivered each year? The Conversation.
Student Thesis and Dissertations

Micro-Consolidation Practices in Urban Delivery Systems: Comparative Evaluation of Last Mile Deliveries Using e-Cargo Bikes and Microhubs

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Publication Date: 2021

The demand for home deliveries has seen a drastic increase, especially in cities, putting urban freight systems under pressure. As more people move to urban areas and change consumer behaviors to shop online, busy delivery operations cause externalities such as congestion and air pollution.

Micro-consolidation implementations and their possible pairing with soft transportation modes offer practical, economic, environmental, and cultural benefits. Early implementations of micro-consolidation practices were tested but cities need to understand their implications in terms of efficiency and sustainability.

This study includes a research scan and proposes a typology of micro-consolidation practices. It focuses on assessing the performance of microhubs that act as additional transshipment points where the packages are transported by trucks and transferred onto e-bikes to complete the last mile.

The purpose of the study is to assess the performance of delivery operations using a network of microhubs with cargo logistics and identify the conditions under which these solutions can be successfully implemented to improve urban freight efficiencies and reduce emissions. The performance is evaluated in terms of vehicle miles traveled, tailpipe CO2 emissions, and average operating cost per package using simulation tools. Three different delivery scenarios were tested that represents 1) the baseline scenario, where only vans and cars make deliveries; 2) the mixed scenario, where in addition to vans and cars, a portion of packages are delivered by e-bikes; and 3) the e-bike only scenario, where all package demand is satisfied using microhubs and e-bikes.

The results showed that e-bike delivery operations perform the best in service areas with high customer density. At the highest customer demand level, e-bikes traveled 7.7% less to deliver a package and emitted 91% less tailpipe CO2 with no significant cost benefits or losses when compared with the baseline scenario where only traditional delivery vehicles were used. Cargo logistics, when implemented in areas where the demand is densified, can reduce emissions and congestion without significant cost implications.

Authors: Şeyma Güneş
Recommended Citation:
Gunes, S. (2021). Micro-Consolidation Practices in Urban Delivery Systems: Comparative Evaluation of Last Mile Deliveries Using e-Cargo Bikes and Microhubs, University of Washington Master's Thesis.

Using the Truck Appointment System to Improve Yard Efficiency in Container Terminals

Publication: Maritime Economics & Logistics
Volume: 15
Pages: 101-119
Publication Date: 2013

This article considers the effectiveness of a truck appointment system in improving yard efficiency in a container terminal. This research uses the truck appointment information obtained from an appointment system to improve import container retrieval operation and reduce container rehandles by adopting an advanced container location assignment algorithm. By reducing container rehandles, the terminal could improve yard crane productivity and reduce truck transaction time. A hybrid approach of simulation and queuing theory was developed to model the container retrieval operation and estimate the crane productivity and truck turn-time. Various configurations of the truck appointment system are modeled to investigate how those factors affect the effectiveness of the truck information. The research results illustrate a clear benefit for terminals utilizing a truck appointment system to manage their yard operation. Reducing the duration of the appointment time window or increasing the appointment lead time could further enhance system performance. Furthermore, the truck information is still effective in improving system efficiency, even if a good portion of trucks miss their appointments.



Authors: Dr. Anne Goodchild, Wenjuan Zhao
Recommended Citation:
Zhao, W., & Goodchild, A. V. (2013). Using the Truck Appointment System to Improve Yard Efficiency in Container Terminals. Maritime Economics & Logistics, 15(1), 101-119.

The Isolated Community Evacuation Problem with Mixed Integer Programming

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Publication: Transportation Research Part E: Logistics and Transportation Review
Volume: 161
Pages: 102710
Publication Date: 2022

As awareness of the vulnerability of isolated regions to natural disasters grows, the demand for efficient evacuation plans is increasing. However, isolated areas, such as islands, often have characteristics that make conventional methods, such as evacuation by private vehicle, impractical to infeasible. Mathematical models are conventional tools for evacuation planning. Most previous models have focused on densely populated areas, and are inapplicable to isolated communities that are dependent on marine vessels or aircraft to evacuate. This paper introduces the Isolated Community Evacuation Problem (ICEP) and a corresponding mixed integer programming formulation that aims to minimize the evacuation time of an isolated community through optimally routing a coordinated fleet of heterogeneous recovery resources. ICEP differs from previous models on resource-based evacuation in that it is highly asymmetric and incorporates compatibility issues between resources and access points. The formulation is expanded to a two-stage stochastic problem that allows scenario-based optimal resource planning while also ensuring minimal evacuation time. In addition, objective functions with a varying degree of risk are provided, and the sensitivity of the model to different objective functions and problem sizes is presented through numerical experiments. To increase efficiency, structure-based heuristics to solve the deterministic and stochastic problems are introduced and evaluated through computational experiments. The results give researchers and emergency planners in remote areas a tool to build optimal evacuation plans given the heterogeneous resource fleets available, which is something they have not been previously able to do and to take actions to improve the resilience of their communities accordingly.

Recommended Citation:
Krutein, K. F., & Goodchild, A. (2022). The isolated community evacuation problem with mixed integer programming. In Transportation Research Part E: Logistics and Transportation Review (Vol. 161, p. 102710). Elsevier BV.
Technical Report

Structural and Geographic Shifts in the Washington Warehousing Industry: Transportation Impacts for the Green River Valley

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Publication: Transportation Northwest (TransNow)
Publication Date: 2009
Establishment level employment data indicate that the warehousing industry has experienced rapid growth and restructuring since 1998. This restructuring has resulted in geographic shifts at the national, regional, and local scales. Uneven growth in warehousing establishments across the Pacific Northwest has likely exerted a significant impact on the regional transportation system, but the extent of these transportation impacts remains unknown. Identifying these impacts is the goal of our proposed study. Recent and ongoing research indicates that growth in the warehousing industry is profound. County Business Patterns data published by the US Census Bureau indicates that at the national level, the number of warehousing establishments grew by just over 100 percent from 1998 to 2005. In 1998 there were 6,712 warehousing establishments in the US. By 2005, that number had increased to 13,483. Although a wide range exists within the warehousing industry, interview data collected by the authors of this proposal indicate that each warehouse handles between 25 and 100 trucks, or 50 and 200 trips, hence the location of warehousing establishments has a significant impact on transportation systems. At the county level, we see that in Washington, King County experienced the strongest absolute growth, adding 59 establishments to the 61 reported in 1998. In relative terms, however, Pierce County added warehousing establishments at a faster rate (159 percent) than any other county. The preliminary data produced in Goodchild and Andreoli’s report clearly indicate that there has been strong growth in warehousing establishments at the national and state levels, but that the growth has not been even across states and counties. From a transportation perspective, these findings suggest that future research needs to focus on how these structural and geographic shifts impact regional and local transportation systems.



Authors: Dr. Anne Goodchild, Derek Andrioli
Recommended Citation:
Goodchild, A., & Andrioli, D. (2009). Structural and Geographic Shifts in the Washington Warehousing Industry: Transportation Impacts for the Green River Valley (No. TNW2009-04). Transportation Northwest (Organization).

Mapping the Challenges to Sustainable Urban Freight

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Publication Date: 2022

Just as there has been a push for more climate-friendly passenger travel in recent years, that same push is building for freight travel. At the same time ecommerce is booming and goods delivery in cities is rising, sustainability has become a policy focus for city governments and a corporate priority for companies.

Why? Cities report being motivated to be responsive to residents, businesses, and the goals of elected leaders. Companies report being motivated by cost reduction, efficiency, branding and customer loyalty, and corporate responsibility.

For its part, Amazon in 2019 pledged to become a net-zero carbon business by 2040. In the wake of that pledge, Amazon financially supported this Urban Freight Lab research examining two key questions:

  1. What is the current state of sustainable urban freight planning in the United States?
  2. What are the challenges to achieving a sustainable urban freight system in the United States and Canada?

Because the research literature reveals that denser, more populous cities are the areas most impacted by climate change, we focused our analysis on the 58 cities representing the largest, densest, and fastest-growing cities in the U.S. found within the nation’s 25 largest, densest, and fastest-growing metro areas. Our population, growth, and density focus resulted in heavy concentration in California, Texas, and Florida and light representation in the Midwest.

Within those 58 cities, we reviewed 243 city planning documents related to transportation and conducted 25 interviews with public and private stakeholders. We intentionally sought out both the public and private sectors because actors in each are setting carbon-reduction goals and drafting plans and taking actions to address climate change in the urban freight space.

In our research, we found that:

  1. The overwhelming majority of cities currently have no plans to support sustainable urban freight. As of today, ten percent of the cities considered in this research have taken meaningful steps towards decarbonizing the sector.
  2. Supply chains are complex and the focus on urban supply chain sustainability is relatively new. This reality helps explain the myriad challenges to moving toward a sustainable urban freight system.
  3. For city governments, those challenges include a need to adapt existing tools and policy levers or create new ones, as well as a lack of resources and leadership to make an impact in the industry.
  4. For companies, those challenges include concerns about the time, cost, technology, and labor complexity such moves could require.

“Sustainability” can mean many things. In this research, we define sustainable urban freight as that which reduces carbon dioxide emissions, with their elimination—which we refer to as decarbonization—as the ultimate end goal. This definition represents just one environmental impact of urban freight and does not include, for example, noise pollution, NOx or SOx emissions, black carbon, or particulate matter.

We define urban freight as last-mile delivery within cities, including parcel deliveries made by companies like Amazon and UPS and wholesale deliveries made by companies like Costco and Pepsi. We do not include regional or drayage/port freight as those merely transit through cities and face distinct sustainability barriers.

Authors: Urban Freight Lab
Recommended Citation:
Urban Freight Lab (2022). Mapping the Challenges to Sustainable Urban Freight.
Technical Report

Cost, Emissions, and Customer Service Trade-Off Analysis In Pickup and Delivery Systems

Publication: Oregon Department of Transportation, Research Section
Publication Date: 2011

This research offers a novel formulation for including emissions into fleet assignment and vehicle routing and for the trade-offs faced by fleet operators between cost, emissions, and service quality. This approach enables evaluation of the impact of a variety of internal changes (e.g. time window schemes) and external policies (e.g. spatial restrictions), and enables comparisons of the relative impacts on fleet emissions. To apply the above approach to real fleets, three different case studies were developed. Each of these cases has significant differences in their fleet composition, customers’ requirements, and operational features that provide this research with the opportunity to explore different scenarios.

The research includes estimations of the impact on cost and CO2 and NOX emissions from fleet upgrades, the impact on cost, emissions, and customer wait time when demand density or location changes, and the impact on cost, emissions, and customer wait time from congestion and time window flexibility. Additionally, it shows that any infrastructure use restriction increases cost and emissions. A discussion of the implications for policymakers and fleet operators in a variety of physical and transportation environments is also presented.

Authors: Dr. Anne Goodchild, Felipe Sandoval
Recommended Citation:
Goodchild, A., & Sandoval, F. (2011). Cost, Emissions, and Customer Service Trade-Off Analysis In Pickup and Delivery Systems (No. OR-RD 11-13). Oregon Department of Transportation Research Section.

Urban Freight Innovation: Leading-Edge Strategies for Smart Cities

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Publication: Coast Guard Journal of Safety & Security at Sea, Proceedings of the Marine Safety & Security Council
Volume: 78:02:00
Publication Date: 2021

Competition throughout the urban freight supply chain is steadily growing. Companies need to devise innovative methods for the transportation of goods from raw materials all the way to the final consumer. From concept to practice, it can be challenging to identify affordable solutions. This article highlights recent research conducted by the University of Washington’s Urban Freight Lab and its partners to explore new methods to reduce transportation costs, improve the customer experience, reduce carbon footprint, and reduce urban congestion after goods leave the shipping docks.

Recommended Citation:
Bill Keough, Anne Goodchild, & Giacomo Dalla Chiara. (2021). Urban Freight Innovation: Leading-Edge Strategies for Smart Cities. Proceedings of the Marine Safety & Security Council, 78(2).
Technical Report

Characterizing Washington State’s Supply Chains

Publication: Transportation Northwest Regional Center X (TransNow)
Publication Date: 2012

The University of Washington (UW), Washington State University (WSU), and Washington State Department of Transportation (WSDOT) recently developed a multi-modal statewide geographic information system (GIS) model that can help the state prioritize strategies that protect industries most vulnerable to disruptions, supporting economic activity in the state and increasing economic resilience. The proposed research was identified after that project as an important step in improving the model’s ability to measure the impact of disruptions. In addition to developing the model, the researchers developed two case studies showing the model’s capabilities: the potato growing and processing industry was chosen as a representative agricultural sector and diesel fuel distribution for its importance to all industry sectors. As origin-destination data for other freight-dependent sectors is added to the model, WSDOT will be able to evaluate the impact of freight system disruptions on each of them. Moving forward, it is not cost-effective to develop case studies in the manner used for these case studies, therefore, the state is currently supporting activities at the national level that will provide methods for collecting statewide commodity flow data. However, this commodity flow data will still lack important operational detail necessary to understand the impacts of transportation changes. This research will begin to fill that gap by developing a transportation-based categorization of logistics chains. The goal is not to capture all of the complexity of supply chain logistics but to identify approximately 15-20 categories within which supply chains behave similarly from a transportation perspective, for example, in their level of scheduling and methods for route selection. Researchers will use existing publicly available data, conduct an operational survey, and analyze GPS data collected for WSDOT’s freight performance measures project to identify the categorization.

Authors: Dr. Anne Goodchild, Andrea Gagliano, Maura Rowell
Recommended Citation:
Goodchild, A., Gagliano, A., & Rowell, M. (2012). Characterizing Washington State’s Supply Chains (No. TNW2012-13).