Last year, I did a review of some of the hidden hydrology of Washington DC showcasing contemporary studies along with a range of historical maps. Since that post, an amazing mapping project by John Davis (@jnddavis) has launched that’s worth some further examination.
“A digital atlas of waterways big and small in Washington, D.C., from the eighteenth century to the present. The online atlas provides a clear sense of the relationship in scale between a city block and the course of an entire river, and facilitates visualizing changes over time in layers or phases.”
A simple blueprint theme provides the foundation for data organized into larger groupings of Aqueduct, Canal, Watefrtont, Watershed, and Sewer. Each of these can be accessed via the navigation or through exploration of the map. The larger theme maps give a short text description and some dashed boxes highlighting more information such as the aqueduct below (click images to see larger images).
The regional scale makes way for the urban, concentrating on the DC area, in terms of Watefront and Sewer, with a cool rollover method of depicting the growth of the sewer system from the 1870s to 90s.
Or the larger system of water conveyance and reservoirs, including the aqueducts, explained: “The original distribution system, built as part of the construction of the aqueduct itself, served only a relatively small area of the city, as compared to the extent of water service now. Shown as a dashed line on the map, the original water-supply mains prioritized government buildings, such as the Capitol and the White House, and areas of concentrated population, like Georgetown. To ensure adequate pressure throughout the system, and to get water to places that were at higher elevation than downtown, the engineers built a series of “high service” reservoirs in high points around the city. Most have been demolished in modernization efforts. A few fragments of trident-shaped fencing, however, remain in the special collections of the Georgetown Public Library, which was built on the site of one of these domed reservoirs.”
This also expands out into the fringes, to show the reach of water systems in watershed, canal, scales, and aqueducts that connect hinterland with urban center. The maps below shows the watershed north of the urban area.
Each map contains the ‘Year Depicted’ so there’s continuity of some form of linearity time-wise (most depicting a timeline from the mid-1800’s through early 1900s and later. There area also some hidden ‘ghosts’ such as a proposed reservoir in the Rock Creek Valley, a dam that could have been as “…engineers eyed the valley as a convenient site for a water reservoir close to downtown. Luckily for the city’s residents, a group of citizens led by Charles C. Glover urged Congress to purchase the land comprising today’s park, and blocked construction of the dam, which would have inundated a large part of the urban landscape.”
It has the feeling of an exploratory video game, as the opening page was fun to see what emerged, and as you zoomed in on scale, the layers of history was revealed in a nonlinear narrative. The highlighted sections were cues, but the users
The scale at some times get’s relatively micro, with zoomed area such as the Navy Yard, below, the nested scales working well in revealing significant water system landmarks.
And the Cabin John Bridge, in which “…engineers designed and built a masonry arch bridge to support the aqueduct’s conduit in its course across the valley. This graceful structure, noted for its simplicity of design and elegant form, was the longest single-span masonry arch in North America for nearly one hundred years.”
The extensive bibliography shows a richness of data that can be layered and unified (often a missing piece for critical analysis using sources of different types). There’s also a complementary essay, in which Davis discusses his take on the digital format in flattening the narrative structure of maps, as well as some methodology, including the pains of digitization and archiving and a switch to open source GIS, and some thoughts on the way we present spatial data. As Davis mentions, scale is one of the key elements that needs to be considered in representation:
“The Water Atlas, because of extensive processing, does convey a sense of place and space to the structures and landscapes it considers. A combination of cartography and orthographic drawing conventions, the Water Atlas resists the ubiquitous tendency to reduce events, structures, and landscapes to icons. Instead, it portrays these structures as visible at an urban scale, and the drawings reflect the true impact of these structures on the landscape. Though not as fluid and seamless as the Google Maps-powered Panorama, or Leaflet, or Neatline; orthographic, architectural scale drawings convey information at that middle scale necessary for representation and analysis of landscape.”
It’s worth clicking and just exploring and seeing for yourself the layers, often easily discerned and sometimes hidden in the relatively simple interface. And as Davis mentions, it works at a scale that unlocks stories at a range that seems both comprehensive and accessible. As mentioned on the Dumbarton Oaks page, the Atlas “… shows the development of the city’s water infrastructure over time, from large features like canals to the sewer grid and water treatment facilities…” adding “It’s interesting to be able to visualize things that aren’t always apparent when you’re walking around the city,” says John Davis, Tyler fellow in Garden and Landscape Studies. “It’s a totally different conception of how the city works.”
As I compile precedents for my own mapping, this stands out as a really inspiring example of what could be. The interface isn’t seamless, but in a way that works in a way where you have to dig a little and move around to unearth all of the secrets. The multi-scalar approach could be adapted to any area and allow for spatial and temporal layering. I likened it to an exploratory video game, but perhaps it more a metaphor for hidden hydrology, that all is not immediately revealed, and that part of the fun is in the journey.
All images – screen shots taken of the DC Water Atlas. The footer for the site reads: “This project was completed as part of work for a Tyler Fellowship at Dumbarton Oaks Research Library and Collection, Washington, D.C. Copyright John Davis and the Trustees of Harvard University, 2016. All Rights Reserved.”