Skip to Content

D.C. Water Atlas

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.

Explore the Water Atlas

As in so many other cities, water is everywhere in Washington, D.C.—and yet it remains largely invisible to most of us, taken for granted or ignored. But D.C.’s waterways and plumbing shape the civic, social, and even commercial lives of its residents just as much now as in the past: the Anacostia, the Potomac, the C&O Canal, Rock Creek. And the crisis in Flint, Michigan, has shown that the questions of where and how cities find their water have tremendous importance for public health, down to the last pipe. 

“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.” During his time at Dumbarton Oaks, Davis, a PhD candidate in history at Harvard working on the history of engineering and infrastructure, has created a digital atlas of Washington, D.C.’s watershed. The “Water Atlas,” as he calls it, shows the development of the city’s water infrastructure over time, from large features like canals to the sewer grid and water treatment facilities. 

Unlike a traditional atlas on paper, the online atlas gives the user a clearer sense of the relationship in scale between a city block and the course of an entire river. It also facilitates visualizing changes over time in layers or phases, rather than having to combine those phases into a single diagram or distribute them over several maps. Davis’s atlas further highlights how different the city’s landscape might have looked if certain rejected projects had been realized. One area of the map allows viewers to see how a proposed dam on the Rock Creek would have created an enormous reservoir in the north part of the city. 

Davis created the Water Atlas using a free open-source application called QGIS, which is widely used for cartography. By tracing information from scans of historic maps found in archives onto existing geospatial data from the United States Geographic Survey, he was able to create a single digital composite that could illustrate changes over time. Davis says that he could imagine this approach being adopted to illustrate infrastructural history for any city: “Every city has documents and maps—the exciting project is assembling the paper data and then digitizing it.” Indeed, he adds, if you had such data for multiple cities, the payoff for historians would be that you could “compare cities and their infrastructures.” 

Davis hopes that the Water Atlas will be useful for both the general public and professional researchers, and also that it might help bring the two groups together. Asked to envision an audience for the project, he describes “a range of people, from academics, or people who have an academic interest in D.C. history, to people in the D.C. area who might be curious about how their water gets to them.” It’s important for academics to invest time in projects like this, he notes, because of the likelihood that the skills of cartography and digital publication will continue to be important to future work in history and the humanities: “Digital maps increase accessibility. You don’t have to go to a library to use them.”