One of the most amazing resources I’ve discovered was the website Philly H20. A comprehensive look at creeks and sewers in Philadelphia, don’t let the charmingly anachronistic website style put you off, as the amazing detail and density of info contained therein. The site is done by Adam Levine, the “the local expert on the history of Philadelphia’s rivers, streams, and drainage systems.” A quick into from the site:
It has been my pleasurable challenge, as a consultant to the Philadelphia Water Department (PWD) since 1998, to try to piece together the fascinating history of the city’s many lost streams. PWD has preserved its own collection of historical material, which is a rich source of information, and I have supplemented that base with research in local libraries, historical societies, archives and relevant departments of the city government.
Besides many useful written records, I have uncovered a wide range of graphic material including paintings and drawings, maps and plans, photographs and surveys. This material stretches across the breadth of the city’s long history, since changes were made in the landscape almost as soon as William Penn began building his new city along the Delaware River in 1682. The bottom line is that, over the course of several centuries, most of the city’s surface streams have been channeled underground and incorporated into the city’s 3,000 mile sewer system.
The section From Creek to Sewer provides a bit more explanation, “As in many urban areas, most of Philadelphia’s surface streams, encompassing many square miles of watershed, were systematically obliterated over the course of the city’s development. Diverted into pipes–their valleys leveled with millions of yards of fill and overlaid with a grid of streets–these streams now flow in some of the largest sewers in the city’s 3,000-mile drainage system. In most cases, these projects were designed as combined sewers, carrying raw sewage along with the stream flow and stormwater runoff.”
A sequence of “Historic and modern stream maps created by the Philadelphia Water Department (using data gathered from a variety of sources), to educate the public about the fate of many of the city’s streams.” The first shows the historic streams, not sure of a date but according to the site probably from around the 1700s or prior to significant permanent settlement.
The current maps shows some intact watersheds in outlying zones, but most of the inner core, North Philadelphia with the exception of Tacony and Frankford Creeks, and mostly gone in South and West Philadelphia areas buried.
The overall landscape change is best represented with the composite map with subsurface piping shown in red, highlighting the underground hydrology still at work, but really emphasizing the removal of most of the creeks and streams in the core and replacement of a much more structured system. This is a pretty common map echoed many times around the world through the 1850s to early 1900s.
Levine has linked a number of interesting maps, such as the early sewerage system from 1895 which already shows the manipulation of streams and construction of diversions along with buried creeks. It also shows that the city was using a combination of sewer and combined systems, which was again used in many cities as a cost-effective strategy. I’m struck now just how Levine curates the material, but offers a historical explanation, on the page From Creek to Sewer, of how and why these waterways were degraded and eventually filled. A short excerpt:
“Since it was then standard sewage disposal practice to direct branch sewers downhill into the nearest stream, they knew that even pristine surface streams would become polluted once the areas around them were developed. Culverting the streams before they became polluted was seen as a positive step to protect the public health. In undertaking these projects, the engineers also hoped to reduce the cost of the city’s infrastructure in a number of ways. Sewage, being mostly liquid, flows most cheaply by gravity–pumping it up a slope is expensive in terms of fuel costs, and is only as reliable as the pumping equipment. By placing sewers in the natural stream valleys, the engineers got the gravity flow they needed, and in the process they managed to avoid the high cost of making extensive, deep excavations. Once the valleys were filled in over the newly built pipes–in some stream valleys in Philadelphia, more than 40 feet of fill was used–the cost of building a bridge each time a main street crossed the stream was avoided as well. “
There’s links to even more map sources as well, including the Greater Philadelphia GeoHistory Network, maps and photos at PhillyHistory.org and digitizd maps available as well as the Pennsylvania Spatial Data Access (PASDA) site. Another huge archive of info is curated a the Places in Time: Historical Documentation of Place in Greater Philadelphia site, which one, especially if you’re purview is Philadelphia, could spend a lifetime digging through. These 1890 Noll maps (below) are great, and Levine mentions some of the qualitative reasons. “This particular map interests me because it shows the many creeks that other maps of the period omitted even before the creeks were actually obliterated. I also appreciate the elevation contour lines, and although the datum used is different by several feet from the current datum, the numbers still give a sense of the rise and fall of the terrain. The street grid also seems more realistic than other depictions, in that it ends at the creek valleys and indicates, with dotted lines, a few streets that have been projected but not built.”
One of my favorites was the photograph of this physical topographic model from the 1940s “… which clearly shows the transition from the flatter terrain of the Coastal Plain to the hillier terrain of the Piedmont.”
One hidden gem was a report from the USGS Fact Sheet FS–117–00 from October, 2000 on “Mapping Buried Stream Valleys in Philadelphia, Pennsylvania” that outlines a process for mapping streams to identify potential risk zones for subsidence. From the introduction: “Specifically requested were a preliminary evaluation of geologic factors that control recent ground subsidence in the Wissinoming
neighborhood (fig. 1) and recommendations for more comprehensive geologic studies that will be required to design a remediation effort and to delineate other neighborhoods that are potentially at risk.”
The use of historical maps of the stream valleys, specifically 1899 USGS topographic maps generated landscape change diagram. From the report: “Examples from the topographic change map included in USGS Open-File Report 00–224. Areas shaded in yellow and labeled Po have been characterized as possible fill. Areas shaded in red and labeled Pr have been characterized as probable fill. A, Map segment showing historical stream valleys of Wissinoming Creek and Little Tacony Creek. B, Map segment showing historical stream valley of Wingohocking Creek.”
The Philly H20 site is impressive in scope, and it’s clear the passion for history, hydrology, and place that are embedded within. Those in the Philadelphia area interested, this should be the first stop – as much of the legwork required in other cities has been done here. There’s tons more info on this site and the more you dig the more info you find, like an Archive with more exhaustive links to many more historical sources and write-ups of key creeks. One by Levine I perused was this “Frankford Creek Watershed: A historical overview of the Philadelphia section” that had one of the most interesting graphics telling taglines: “A Snake that will be Straighted Out”, indicative of the conversion of streams at the time.
Finally, I’d be remiss if I didn’t mention one of the most incredible Philadelphia projects, from the early 1990s. The brainchild of Anne Whiston Spirn when she was at Penn and later through MIT, the West Philadelphia Landscape Project had a “…mission is to restore nature and rebuild community through strategic design, planning, and education projects.” Over the course of 25 years this project provided a unique model for community engagement and urban ecosystem restoration that has permeated others work since.
A focus of the work is Mill Creek, where the project sought “…to demonstrate how to create human settlements that are healthier, economical to build and maintain, more resilient, more beautiful, and more just.” The focused Mill Creek Project investigated hydrology and history with an aim to “…explore how a new curriculum organized around “The Urban Watershed” could combine learning, community development, and water resource management.”
This was some of the first examples of GIS based historical mapping I had seen, and although the tech was early, the impact on me was long-lasting. This is perhaps my first exposure to the concept of historical mapping and urban streams, and I vividly remember reading about it in undergrad and being blow away. I mention it just in passing as a Philly endnote (because it deserves a more complete review as a case study) in greater detail. More on this work to come!