by Rick Pruetz, Vice President, Ecocity Builders

Rotterdam’s Ecocity World Summit 2021-22, like its 13 predecessors, created the forum for a priceless exchange of ideas and learnings from throughout the world. Over 80 papers contributed to Summit 21-22 have been collected in Conference Proceedings within four chapters spanning the four pillars of the Ecocity Framework and Standards: urban design, buildings and transportation; bio-geophysical conditions; socio-cultural features; and ecological imperatives. In addition, a fifth chapter incorporates nine papers prepared for a simultaneous conference held in Cairo, Egypt on sustainable development after the Covid era.

At 990 pages, few people are likely to sit down to read the EWS 2021-22 Proceedings from cover to cover. But anyone browsing the abstracts will be impressed by the scope of the worldwide ecocity movement and will inevitably dive into individual papers on case studies, new approaches, or scholarly analyses of strategies being tested in every corner of the globe.

I was particularly drawn to a paper exploring the multiple benefits of active transportation in two cities in India (Mahadevia et. al. 2022). Prior to reading this study, I was primarily aware of the many ways that walking and bicycling in the U.S. and Europe promote mobility justice, health, transportation options, community cohesion, and economic development as well as reductions in GHG emissions (Pruetz 2016; Pruetz 2021). Darshini Mahadevia and two colleagues from Ahmedabad University confirm many of these conclusions by estimating the impact of existing and proposed non-motorized transport in the cities of Surat and Udaipur in the categories of access, safety, and health. In Surat alone, the active-transportation improvements are estimated to improve access by 34 percent, reduce crashes by 37 percent, and cut GHG emissions by 28 percent. The study notes that almost half of all trips in these two cities are currently accomplished by walking or cycling but that travel is shifting toward personal motorized vehicles. Improving active-transportation infrastructure would help keep these and other cities in India from repeating the mistakes made in the US and many other countries that have heavily favored personal motor vehicles and now find themselves having to restore a more balanced mode split in order to achieve the various benefits resulting from a robust active transportation network.

In Chapter Two, one paper notes that the benefits of shifting from concrete and steel construction to wooden structures are widely recognized but that many jurisdictions are not yet quantifying these benefits at the municipal level in order to achieve ambitious targets for GHG mitigation and carbon sequestration. In a case study in Menden, Germany, the authors applied a geodata-based web-GIS system called “Holzbau-GIS” to six types of development and calculated significant GHG emission reductions and carbon sequestration increments when timber construction was compared with conventional building practices (Zernicke 2022).

In Chapter Three on socio-cultural features, architect Peter Engel uses a thought experiment to illustrate how the toxic polarization of today’s societies is largely generated by physical separation into uniform blocks segregated by race, ethnicity, religion, or political persuasion. With a computer model, he demonstrates that segregation can be unwound using inspiration from tide pools, where diverse creatures mingle in an environment characterized by a combination of four characteristics: mixing, flow, porosity, and change. He then shows how tide pool features can be applied to human environments by replacing rigid, compartmentalized boxes with spaces in which various activities mix, blend, and blur together, generating changes in human interactions much like the dynamic that happens when surges of water add and swirl various creatures into contact with each other (Engel 2022).    

In Chapter Four on the ecological imperative, a professor of urban planning at the University of Tehran reports on methods of evaluating progress toward sustainability using the Greener Cities Partnership and the City Prosperity Initiative (Arbab 2022).

Finally, nine papers, assembled under the title of Exploring Horizons of Sustainable Development Post-Covid-19 Era in Egypt, examine diverse aspects of the need to plan public spaces, neighborhoods, and cities with mental and physical health in mind.

To freely download this treasure trove of all things ecocity, use this link:


Arbab, P. 2022. The Outlook for the Greener Cities Partnership (GCP). In Ecocity World Summit 2021 Conference Proceedings. Oakland: Ecocity Builders.

Engel, P. 2022. A Lesson from Tide Pools: Designing Social Spaces with Flow. In Ecocity World Summit 2021 Conference Proceedings. Oakland: Ecocity Builders.

Mahadevia, D., K, Gounder, and S. Lathia. 2022. Exploring Co-Benefits of Active Transportation in a Low Carbon Future: A Case of Two Indian Cities. In Ecocity World Summit 2021 Conference Proceedings. Oakland: Ecocity Builders.

Pruetz, R. 2016. Ecocity Snapshots: Learning from Europe’s Greenest Places. Arje Press.

Pruetz, R. 2021. Prosperity Comes in Cycles: Bikeways and the Virtuous Cycle. Arje Press.

Zernicke, C., C. Mattes, C. Jolk, A. Hafner, and A. Abecker. Holzbau-GIS: Presenting First Results of GIS-Based Modelling on Reduction of Greenhouse Gas Emissions through Constructing and Renovating with Timber on a Municipal Level. In Ecocity World Summit 2021 Conference Proceedings. Oakland: Ecocity Builders.

About the author

Rick Pruetz

Rick Pruetz, FAICP, is Vice President of the Ecocity Builders Board and an urban planner who writes about sustainability, most recently Ecocity Snapshots: Learning from Europe’s Greenest Places and Smart Climate Action through Transfer of Development Rights.