This blog post was written for and first published on the Port City Futures website.

Ports, and their neighboring cities, are dense concatenations of infrastructures. Many of these are things enabling other things to move. Ships bear their loads through bays and, when heading inland, canals; at docks, stevedores load the wares onto lorries, which carry them along roads and across bridges; and all the while, pipes channel water, oil, or gas to and from facilities. Indeed, from a certain point of view these ports themselves appear infrastructures. They are nodes through which many things we use must pass on their way from sea to land; the connections established by these flows make such interior areas what they are. However, as noted in our recent call for papers, port cities also host another type of infrastructure. These are things not facilitating flows inland but preventing them, like seawalls, dikes, and other coastal defense structures. The latter aim, as I have written about previously, to ‘saturate’ space, meaning ensure control by confining all parts and parties to their ‘proper’ places (most notably the sea and rivers, which must be kept separate from the land).

Imagine the color of such infrastructures and you will probably see ‘grey.’ Planners and architects, too, often call them this due to the hue of the materials normally used to construct them (for a definition and examples of ‘grey infrastructure,’ see Kapetas and Fenner’s article). These are steel and concrete, whose spread enabled the massive expansion of infrastructure during the last century. When politicians promise new investments in or “leveling up” of our infrastructure, they normally mean the grey variety: more roads, more bridges, and, in countries like the Netherlands, more coastal defenses. However, both academic and professional planners are increasingly campaigning for what they call ‘green infrastructures’ instead. The University of Idaho’s Gary Austin, for example, writes in his 2014 book that “rivers, streams, lakes and oceans compose a natural infrastructure” that can not only support ecological functions but also, unlike grey infrastructure, generate “pollution mitigation, recreation, economic value, urban structure, scenic and other human benefits”. Green infrastructures emerge, he writes, when the former ‘natural’ or non-human components are intentionally networked with each other and manmade objects in order to provide these and other such services.

It’s not hard to see why people concerned about coastal areas might want to green their infrastructure. For at least a century, such areas have invested in grey infrastructure, often as a sign of modernity. In many countries, however, this graying is now recognized as a significant cause of current environmental problems. For example, in Japan, where I conduct research, 90% of tidal wetlands were drained to enable development between the 1970s and 1990s. This severely impacted biodiversity and may have increased vulnerability to tsunamis. In New Orleans, similarly, channels built to facilitate shipping eroded wetlands that had protected the city from storms. Some also had the unintended consequence of funneling storm surges into the city itself. In both Japan and New Orleans, governments responded with more concrete, building seawalls and dikes to protect places from the effects of their own development. Scholars debate whether these saved lives or created moral hazards (see Adams and Aldrich). What is clear, however, is that they often further damaged ecosystems.

As a result, there is a growing push in many coastal areas to both turn surviving wetlands, coastal forests, and other ‘natural’ phenomena into “green infrastructures,” make new such phenomena or re-make those destroyed during development, and manage the resulting ecosystems in ways benefiting both human and nonhuman populations. Many of these efforts revolve specifically around protection. In Guyana, for example, Sarah Vaughn describes how scientists are attempting to shift coastal protection efforts away from grey infrastructures and towards mangrove forests, which provide a wide variety of ecosystem services to coastal residents. In Japan, similarly, many groups inspired by ecologist Akira Miyawaki proposed planting “coastal protection forests” (bochōrin) instead of building new seawalls to protect ports and their neighboring towns and cities after the 2011 tsunami. This, they hoped, would not only buffer the coastline but provide an opportunity to restore lost ‘native’ forests. While Dutch ports still rely heavily on grey infrastructure for protection, like the Maeslantkering, there has also been a turn here towards the green kind, with the ‘sand engine’ (Zandmotor) a paradigmatic (if yellow) example. Popular with Dutch surfers, it provides a good example of how such infrastructures can integrate ecological, protective, scenic, and recreational functions, as Austin claims.

These are welcome developments, given the damage caused by greying our coastlines. However, green infrastructure projects raise their own kinds of issues. In Japan, Aike Rots (2019) has shown how one effort to plant a new protective forest with evergreen trees ‘native’ to the region faced resistance from locals wanting to restore coniferous woods (imported from the South) associated with shrines. This resistance was rooted as much in competing ideas of local and national identity as ecology. Many ecologists also opposed the plans, however. They argued that, paradoxically, planting new trees could damage other fragile ecosystems. “In [Northeast Japan] as much as elsewhere,” Rots concludes, “there is not a single ‘nature’ that has to be restored; there is a diversity of ‘contested natures’”. The project, unsurprisingly, did not succeed. In the Netherlands, green infrastructure projects have proven more successful. However, efforts to export these as models for other countries have proven controversial. To make ‘room for the river’ in Southeast Asian port cities, for example, Lizzie Yarina describes how governments are evicting their poor, increasing environmental injustice.

These issues recall a basic claim made by anthropologists studying infrastructures. They are not, as those building them often claim, primarily technical objects, decisions about which should be left to engineers and other experts. Rather, they are political artefacts: both products of and arenas for contestation over what we should value (and which ‘we’ gets a voice). Deciding the height of a seawall only through tsunami modeling, for example, neglects the impact of that height on other social and cultural domains. Give people a voice and they may, as I found in the case of North-East Japan, choose to prioritize the latter. All this is as true of infrastructure’s green as grey varieties. Accordingly, in an era where political (in)decisions are leading us to catastrophe, sustainably protecting ports from rising tides requires more than changing the color of infrastructure. We also need to change the decision-making processes and “rule of experts” depoliticizing what are fundamentally political questions regarding which visions of the common good to—often literally—make concrete.

Acknowledgement
This blog has been written in the context of discussions in the LDE PortCityFutures research community. It reflects the evolving thoughts of the authors and expresses the discussions between researchers on the socio-economic, spatial and cultural questions surrounding port city relationships. Special thanks for comments and reviews to Carola Hein, Tianchen Dai, Stephan Hauser, and Hilde Sennema.