The above diagram shows water main connections at Toronto's High Level Pumping Station as they were in 1988. Rather than a simple, gridded system, water distribution mains conform to the location of plants, pumps and reservoirs, as well as the dictates of history and topology.

City of Pressures 1: Water Distribution

Michael Cook

On this website, I have long focused my efforts to revealing the physical spaces contained within underground infrastructure like sewers and utility tunnels, and to countering the general impression of these systems as abstract networks that is promoted by the authorities responsible for their operation and maintenance. However, in what will be an ongoing series I am going to start talking about physical infrastructure systems that can't be apprehended and inhabited in this way — because their physical spaces are thoroughly ancillary, and because their main pipelines are not only pressurized but usually unaccompanied by any sort of human-passable tunnel.

Watermains. The word can only invoke visions of puddled intersections, flooded basements and construction equipment. We haven't been given the opportunity to think about the system when its presence in our lives isn't mediated by disruption and catastrophe.

Already hidden away beneath the pavement, in the fallout of the September 11th attacks our urban water distribution systems became completely unapproachable: North American municipalities that once took pride in their treatment and pumping systems and put them on public display extinguished that last impulse to celebrate their infrastructure. Our most essential of public services, clean water provision, is in most cities now kept locked away behind barbed wire, checkpoints, and nonsensical "No Photography" policies.

As I mentioned recently, Toronto Water has apparently taken a step towards reversing this trend, and will be opening the city's flagship R.C. Harris Water Treatment Plant to tours during this year's Doors Open weekend. I can only hope that this is merely the beginning of a broader infrastructural 'detente' within the organization, that will result in a much deeper commitment to public involvement and engagement of the sort I have recently written about. In the meantime, it at least presents a good icebreaker to thinking about the presence and possibilities of water supply systems in today's urban landscape.

R.C. Harris Purification Plant, Toronto. City of Toronto Archives, Fonds 200, Series 372, Subseries 72, Item 2033.

View of Hamilton, Ontario's Barton Reservoir when it was in service (1859-1958).

Water System Visibility

When it opened in 1941, and really until the post-September 11th security panic put the final nail into the coffin of 'public' works, the R.C. Harris plant was the public face of water service in Toronto. But in earlier decades, urban water service was a visible component of public space in many cities, including Toronto. The Rosehill Reservoir near Yonge and St. Clair was left open to the sky when it was built in 1873, an "organic machine" as Michael McMahon describes it in his contribution to HTO: Toronto's Water from Lake Iroquois to Lost Rivers to Low-Flow Toilets, the reservoir was an artificial lake that employed sunlight, wind action and uncultured micro-organisms to maintain the potability of water drawn from Lake Ontario and pumped up to it in the decades prior to chlorination. Despite public outcry from residents attached to their neighbourhood lake, Metro Toronto chose to cover the reservoir in the 1960s, claiming that the toxic impact of bird droppings and air pollution meant that it would otherwise have to rechlorinate the water leaving the facility before it could be sent to homes.

In Hamilton, Ontario, the remains of that city's first reservoir can still be found on the shoulder of the escarpment, partway up the Kenilworth access. The Barton Reservoir was completed in 1859 to provide 11 million gallons of storage and gravity service for Hamilton's 1857 waterworks, designed by the public works engineer Thomas Keefer. Like the Rosehill Reservoir in Toronto was conceived as the centerpiece of a manicured public park. Replaced in 1958 by the modern, underground Kenilworth Reservoir just down the road, today the Barton Reservoir's rough-hewn stone block walls and rubble basin enclose only marshland, and the overgrown and partially fenced-off area sees few visitors apart from nighttime partiers and the occasional hiker adventurous enough to stray from the nearby Escarpment Rail Trail. In 2009, request was made to the City of Hamilton (PDF) to designate the reservoir site as a historic property under the Ontario Heritage Act. The designation was granted later that fall, although it remains to be seen whether efforts will be made to make the reservoir an authorized part of the city's landscape again, and indeed to return its basin to the open ampitheatre described by John Terpstra in the H Magazine article linked above.

Much of New York City's famed Catskills and Delaware water system remains above ground, in open reservoirs that collect the output of an entire watershed and channel it through spillways, sluices and ultimately tunnels to a thirsty city as much as 200 km distant. While health and security concerns have eroded permitted public access and activities in and around the reservoirs, these physical structures, so evocatively photographed in the 1990s by New York photographer Stanley Greenberg, can in many cases still be seen and visited even in the current era.

In the early decades of urban public works construction in North America, physical structures like reservoirs and filtration plants were crucial sites for celebrating public-funded infrastructure, for encouraging universal use of the services, and for legitimizing the often massive (at least to the era's conservative ratepayers) public expenditures that secured their construction. As access to these services became normalized (although in many places still subject to deplorable forms of institutional discrimination) and the infrastructure thus assumed to be of little general interest, and as we moved to increasingly bureaucratized, managerial and defensive public works institutions (whose interest has rarely been to invite the public in), we stopped making these kinds of grand statements. Chemical treatment and security cultures succeeded in shuttering most of the remaining visible and accessible monuments of water systems, while their buried presence in our neighbourhoods goes unremarked on except when the mains fail or need replacement.

St. Louis Water Distribution System (c. 1908). From "Public Water-Supplies; requirements, resources and the construction of works" 2nd Edition (1908).

Water Distribution

Urban waterworks are more than just their reservoirs and their 'palaces of purification', they are the hundreds or thousands of kilometres of distribution piping that link your house or workplace to the water source (whether a lake or river, well farm, or in the case of New York City and Los Angeles, entire watersheds covering thousands of square kilometers). Despite the fact that in most modern cases the connecting infrastructure consists all but entirely of closed, pressurized piping, we shouldn't think about this system as a black box, as an abstract network that links your tap to the plant with nothing in between. If the frequent water main breaks that create so much disruption aren't enough to convince the reader of the spatial specificity of water service (and catastrophe), consider also that the engineering dreamwish of a perfect, gridded network (see diagram above) is largely a fiction, and that your water system is shaped as much by geography, politics, and historical decisions as any other dimension of the city.

In Toronto, water service may be ubiquitous, but with the supply originating at four treatment plants along the lakeshore, water is sent to the more northerly (and elevated) areas of the city by a comparatively small number of trunk mains that are far more geographically distinguished.

Corporation of Metro Toronto Water Supply System, 1985. The map shows the city's numbered pressure districts and Metro's network of main distribution lines. These mains remain the backbone of the amalgamated city's water system today.

Toronto's Water Distribution System

Toronto, like most cities, is spread across an area of varying topology, with elevation ranging from 75 m above sea level at the Lake Ontario shoreline to 209 m at the intersection of Steeles Avenue and Keele Street on the city's northern boundary. As a result, the city's water system is divided into a series of 'pressure districts' serviced by different pumping stations and gravity reservoirs, in order to maintain an appropriate pressure (generally between 50-100 psi) at street level to serve household and commercial customers and to feed fire hydrants when required. The map above shows those pressure districts as they were designated by Metro Toronto Works in 1985, along with the principal trunk transmission mains and pumping stations serving them.

In 1985, Pressure District 1 encompassed the lower part of the old City of Toronto, along with southeastern Scarbourough (1E) and a small area around New Toronto and Long Branch in south Etobicoke (1W). Pressure District 2 ran across the city in a tight band below the old Lake Iroquois shoreline, from Etobicoke's western boundary to Victoria Park in the east (beyond which the Iroquois shore meets Lake Ontario as the Scarborough Bluffs), and reaching north from there to Eglinton along the valley of Taylor-Massey Creek. Pressure District 3 included most of the former Borough of York, neighbourhoods like Richview in Etobicoke, and reached north along Jane Street and the Black Creek into North York; Don Mills, at similar elevation, was served by District 3E. Most of the rest of the city was served by various divisions of Pressure District 4, excluding the central part of North York (Downsview and Willowdale) which, higher than just about any other part of the city, sat in Pressure District 5. Some changes may have been made to this numbering system after amalgamation (as trunk transmission and local service provision were reintegrated under Toronto Water after years of being the separate domains of Metro Water and local borough works departments), but the broad strokes of the system and its principal mains remain largely unaltered.

The Toronto Star has been chronicling (1, 2, 3) the ongoing process of replacing a major transmission main (built in 1915/1923) that currently runs beneath Avenue Road and Duplex Avenue (the new main will run straight up Avenue Road), carrying water from the High Level Pumping Station up through the lower part of Pressure District 4 to the major transmission main that runs beneath Bayview Avenue and reaches all the way up to Richmond Hill in York Region (York Region municipalities draw their drinking water from a variety of sources, but much of it is purchased from Toronto).

The Star's coverage to date has focused on the disruption to car drivers caused by excavations along a major north-south commuting route, and on 'dirty jobs' profiles of the diggers and engineers working on the project. But equally interesting is the fact that it gives the neighbourhood a chance to see not only the middling 6- or 9-inch mains that supply their homes and which we see dug up on a far more regular basis, but the veritable spine of their water supply, the nearly 1 meter diameter tap route through which the waters of the lake are driven against gravity to Forest Hill homes, and to the suburbs beyond, by pumps at R.C. Harris, at the Island Filtration Plant, at the John Street Pumping Station (shared with Enwave), and finally at the High Level Pumping Station just down the road at Cottingham and Poplar Plains Road.

It has been far too easy for the Star to just cover this as an infrastructure project, and to report on natural groundwater in the area as an engineering problem rather than as a potentially significant revelation for neighbourhood residents. A dry discussion about the challenges and delays posed by mechanical dewatering is apparently of greater interest to the newspaper than the magical fact that there is water beneath the intersection of Avenue Road and St. Clair, right around the former confluence of the headwaters of Mashquoteh Creek, a tributary of Rosedale Creek.

Take this revelation, this discovery of the in-situ watershed that we pretend disappeared with the installation of a sewer system, and then add to it the equally magical fact that we're in the act of running our own artesian river back up through this area. The new main isn't just a tiresome pipe, it's another link to water in a neighbourhood with precious few since we buried the Yellow Creek and Rosedale Creek (the latter into sewers that the Star reports will pose challenges for the watermain diggers). Just as the main connects Forest Hill to the lake, it also provides another dimension in which this neighbourhood is connected to the North York and Richmond Hill neighbourhoods from which hail the commuters that buzz down Avenue Road and back every work day. It's a failure of the imagination of Toronto Water that they're not putting the story of this water and its destinations front-and-centre in their communications about the project, and an equal failure of the Toronto Star that they're choosing to make the story about the vaguely interesting but ultimately forgettable engineering of the project, rather than its contributions and renegotiation of the lasting ecology of the community and landscape this pipe is being run through.

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