A MAN-MADE WATERCOURSE ABSORBED INTO THE NATURAL LANDSCAPE - ENGLAND’S MANCHESTER SHIP CANAL: A case study in adaptive re-use and brownfield restoration
Introduction: protected areas in the built environment
When thinking about the concept of protected natural areas, there is often a tendency to consider such protected natural areas in contrast to or in opposition to artificial man-made structures. Similarly, when thinking about the concept of protected natural areas, there can be a tendency to assume that the appropriate location for such areas is geographically remote from the more built-up urban environment.
As Anne Whiston Spirn noted, 'The belief that the city is an entity apart from nature and even antithetical to it has dominated the way in which the city is perceived and continues to affect how it is built. The city' must be recognized as part of nature and designed accordingly’ (Spirn 1984: 5). In a similar vein, the International Union for the Conservation Nature (IUCN) advised: ‘As our cities continue to grow, we must not abandon the protection of natural areas to the pressures of urbanization, but should instead defend such places, and indeed try to create new space for nature within the urban fabric—even within the centers of cities’ (Trzyna 2014: p. v).
The story' of the Manchester Ship Canal in England challenges the traditional assumptions and thinking described by Anne Wharton Spirn, and forces us to reassess nature’s place in the urban context as Spirn and Trzyna advocate. With the Manchester Ship Canal, we find an artificial man-made watercourse constructed at the end of the nineteenth century' that, over time, has in both appearance and function become more like a natural river, and that has become the setting for a series of canal-side nature parks that are reshaping the identity and economy' of Greater Manchester. It is an adaptation of industrial infrastructure to new urban uses: a bluegreen space parallel to the creation of greenspaces on brownfield land.
The experience with the Manchester Ship Canal, of an urban man-made watercourse that comes to be viewed as part of the natural landscape, is also happening in other cities, such as
Los Angeles, California and Portland, Oregon in the United States. In Los Angeles, the natural Rio de Porciuncula (also known as the Los Angeles River) was straightened and encased in a uniform concrete trapezoidal cover in the 1940s, and renamed by government authorities as the Los Angeles County Flood Control Channel. Yet, in recent decades, concrete has been removed from portions of the channel, parks and bike paths have been built along its banks, and the greening of the Los Angeles River has become a source of civic pride (Gumprecht 2001).
In Portland, annual floods south of the Columbia River created a network of marshes and wetlands adjacent to the river. From 1919 to 1921, in an effort to drain this area for farming and built structures, settlers built levees to prevent the annual floods (Multnomah County 2016). These levees profoundly affected the character of the floodplain. The natural marsh ecosystem was transformed into a highly managed system of agricultural lands and an earthen channel (which collected rainwater and irrigation runoff). The levees' elimination of spring freshets dried out lakes and ponds and prevented salmon from migrating into and out of the former marsh. Yet more recently, to increase flows into the earthen channel and restore connectivity, water from Columbia River is now being diverted into the earthen channel to support spawning salmon and a dense riparian habitat, and these flows are then returned to the river. The earthen channel has been rechristened with the more poetic name ‘Columbia Slough’ and is now used by the community for canoeing and kayaking (Barthel n.d.; Portland Bureau of Environmental Services 2008; Columbia Slough Watershed Council 2009).
On an even grander scale, there is the Erie Canal in New York State. Completed in 1821 the Erie Canal (formerly known as the New York State Barge Canal) quickly became obsolete as a commercial shipping route when the railroads replaced canal transport (Roberts 2017). However, the Erie Canal is now part of an extensive corridor of parks and trails that extend 584 km from Albany to Buffalo, forming urban blue and greenways through cities such as Syracuse and Rochester. Now sometimes called the ‘Artificial River’, the Erie Canal has been absorbed into the urban and natural landscapes of upstate New York (Sheriff 1996).
In this sense, the Manchester Ship Canal, the Los Angeles River, the Columbia Slough, and the Erie Canal stories represent a new variation of the established architectural concept of ‘adaptive re-use’. Adaptive re-use has generally referred to the ways that older vacant historic industrial buildings have been reclaimed and modified for new uses, such as residences, restaurants, and art galleries. The adaptive re-use concept seems equally applicable to the transformation of use of older underemployed canals, only this re-use takes place in an expansive outdoor landscape rather than within the walls of a building (Zaitzevsky and Burnell 1977; Wong 2017).
This chapter begins with the history of the Manchester Ship Canal, both in terms of its decline as a shipping corridor and as a setting for canal-side open spaces such as Moore Nature Reserve, Wigg Island, Woolston Eyes, and Trafford Ecology’ Park. The chapter then compares the shipping and parks experience of the Manchester Ship Canal with that of the Erie Canal in the United States.
With both the Manchester Ship Canal in England and the Erie Canal in the United States, what we see is a changing landscape and new emerging open space roles for shipping canals that have outlived or expanded beyond their originally intended economic purpose. The stories of the Manchester Ship Canal and Erie Canal hold potential lessons for other cities that may also be looking to re-envision and repurpose deteriorating older underemployed man-made watercourses as new urban environmental amenities.
