The most recent October issue of Landscape Architecture Magazine (LAM) has a great story on hidden hydrology inspiration Anne Whiston Spirn, FASLA, titled Where the Water Was, which highlights the “long arc” her work in West Philadelphia, namely the “water that flows beneath it.

The aha moment is recounted in the article, the inspiration for the poem linked above “The Yellowwood and the Forgotten Creek“, as recounted in the article, she “was on her way to the supermarket, when she was stopped at a gaping hole where the street had caved in over the Mill Creek sewer.  “I looked down and saw this big, brown rushing river, and all this masonry that had fallen in. I thought, ‘My God, there are rivers underground. We’re walking on a river.'” (122)  Sprin’s work spans decades since that story in 1971, predominately around Mill Creek which was “buried in the brick sewer pipe in the 1880s”, morphing into the West Philadelphia Landscape Project (WPLP) [covered in brief on our post on Philadelphia here].  While I was inspired as a student and professional by her work on books like The Landscape of Landscape and The Granite Garden, her work on hidden streams was perhaps the most powerful for me, both as an object of study but more broadly to leverage this research into a vehicle for positive change.  As mentioned, the WPLP website “contains maps, historical documents, reports and studies.” including an updated interactive timeline, and some newer updated interactive mapping which is good to see, as much of the interface until late was a bit dated.

A long way from the preliminary maps in CAD as part of the early mapping in the late 1980s and early 1990s.  The sophistication and breadth of this work at the time is telling thought, and I remember seeing these for the first time in college and being amazed.  The article shows what many of us know, which is how much of what we take for granted in technology of mapping that’s available to us today, and how hard it was, physically and sometimes politically to get good information.  As Spirn mentions “You had to literally go out and field check.” (134)

The takeaways of this early work was to both connect the above ground with what was underground, both historically in predevelopment hydrology but also with sewer routing and burial of waterways.  As mentioned, the idea that is a constant with Spirn of “reading the landscape” was instilled as a way to understand the full picture of a site or district.  The connection of the physical features with the social is also evident as Spirn is quoted: “It’s a pattern of eastern old cities and across the U.S., where lower-income folks are living in the bottomlands… Many are literally called the Black Bottom.” (126)  From this analysis, the idea of mapping and using vacant lands was a way to solve the hydrological problems of flooding or sinkholes, but also to revitalize communities.

The Buried River from Anne Whiston Spirn on Vimeo.

How to do it was an issue, as recounted in the article, ideas where one thing, but changing minds into action was another.  McHarg’s Design With Nature inspired her writing The Granite Garden, not as an academic treatise, but rather “…to fill a void.  Scientific journals, historical documents, topographic maps, all sorts of materials contained a wealth of information for ecological designers, but no one had pulled it together in a comprehensive, understandable book that could guide designers as well as the public.”   (127)  This book influences generations of landscape architects in many ways beyond merely historical ecology, but in how we think and communicate.  For the project itself, Adam Levine (who is the mind behind the PhillyH20 project which i documented previously) found the 19th Century maps “that showed Mill Creek and its tributaries before the land was developed. Spirn’s students digitized those surveys and overlaid them on the city’s topographic maps, finally getting an accurate depth of fill along the floodplain. “We found it’s buried up to 40 feet in some areas…”” (134)

The actions were part of this research as well, and many interesting strategies came from the Vacant Lands report (see here), as well as a number of other projects, many of which took a long time to become reality, or came with ups and downs of poor implementation or.  The successes came, owing to the persistence of Spirn and her local compatriots in West Philadelphia, summed up in the article simply:

“Change is a bit like a buried creek. It’s hard to remember its origins. Its many branchings are invisible.” (137)

The legacy locally is a series of activists still working on landscape and community building.  Beyond that, there’s an army of landscape architects inspired by this project and her writings, and her life-long spirit of advocacy.  A great homage to a wonderful teacher and landscape hero.  Lots of great info in the article – which unfortunately isn’t available digitally at this time.


HEADER:  Snapshot of Interactive Map of Mill Creek – via

Our understanding on the arc of history around hidden hydrology is informed with maps and accounts from early explorers and settlers to areas, augmented with records, diaries, and oral histories. Often this neglects and misses the valuable stories of indigenous inhabitants of areas, and leaves us with a significantly shorter timelines for reference. The role of archaeology is vital to unlocking the layers of hidden hydrology that don’t emerge from these illustrative written histories, so I was really intrigued with a recent tweet from the Museum of London Archaology (MOLA) (Twitter: @MOLArchaology) that told of their current work, called London’s lost river: the Tyburn.  From their site, the project is the result of “…a team of expert geoarchaeologists  whose work is helping us to understand London’s lost rivers. As an educational charity, we want to share what we’ve learnt, so please join us to explore the story of this long-lost river.”   

Using the interactive ESRI Story Map, MOLA developed a narrative to describe the process and some of the key findings.  Much of the work is conducted along with construction sites, which gives an opportunity to look below the surface while excavation is happening.  The River Tyburn flowed on the north bank of the Thames, and most famously, was routed and defined the space called Thorney that Westminster Abbey was located, seen in this view circa 1530.

The origins of the river are tied to the longer history of the Thames, which is illustrated (see header image) and reaches back to the last glacial period of 11,500 years ago.  From there in, “…this new epoch, known as the Holocene, the Thames began to take the shape we know today, but many channels still criss-crossed the river’s floodplain within the wide gravelly valley. One of  these channels was the Tyburn, which flowed into the Thames.”   In this zone, there are hundreds of sites, or ‘deposit logs’ that are recorded, and these are modelled to create a snapshot, particularly focusing on the depths of land (depicted below as green – high ground and purple – low ground.  From this model, “projected possible courses for the River Tyburn, following the lowest-lying areas of the modelled 11,500-year-old topography.” with a caveat that “the river would have migrated over time.”

Drilling down (literally) into the specificity of the deposits shows the ranges of material and how it can inform, looking at “ancient flora and fauna” and focusing on things like Diatoms, Pollen, and fossils of things like “Ostracods, the remains of small crustaceans, can indicate salinity, water depth, temperature, water acidity/alkalinity”.

Below is “…a cross section, or transect, running north–south from Westminster to Vauxhall Bridge, along the north bank of the Thames. This connects deposit sequences recorded in trenches and boreholes, and helps us look at these sequences over wide areas.”

They also connect their study with the work of Barton and Myers 2016 book ‘The Lost Rivers of London‘ (see here for a post on the same), which speculated on a number of scenarios for the Tyburn, and various routes.  There’s some graphic things I’d change here (namely it’s hard to read the Barton and Myers layers) but the concept is interesting, to overlay varying studies and ‘proof’ the concepts of routing. In essence, does the data reflect the speculation on routes, either reinforcing or disputing what was speculated?  The below map is a composite of this

There’s links to some coverage in London Archaeologist, such as a 2014 article in which “… Tatton-Brown and Donovan used historic documents and maps to suggest that the medieval waterways separating Thorney Island from Westminster were man-made and that the Vauxhall Bridge route was the original and only course of the river.”  The 3D views of the route and the illustration of the provide a speculative view of the area.  From the site:  “Our topographic model supports Barton and Myers’s suggestion that discussing two distinct branches (towards Westminster and towards Vauxhall Bridge) is an over-simplification of what was probably a more complex delta-like network, as shown [below] (artist Faith Vardy).  This geoarchaeological study provides a baseline for reconstructing the evolving landscape; when combined with historical records and archaeology, even more detailed models could be created. The research done by others, such as Tatton-Brown, which focuses on later periods, may be supported by geoarchaeological work undertaken in the future.”

The concept of geoarchaeology is pretty fascinating as well, and worthy of some further exploration.  In the interim, you can check out the MOLA site for what their team does, which focuses on using “…auger or borehole surveys and interpret the archaeological soils and sediments retrieved, allowing us to reconstruct past landscapes and environments.”  The reason for this particular subset is to pick up “…where the archaeology is too deeply buried for traditional excavation techniques to succeed. It is also a cost-effective archaeological evaluation tool and geoarchaeological deposit modelling, which maps buried landscapes and deposits.”  This is relevant as the surface remnants of these, but the underground deposits, so they work in a “…wide range of depositional environments, including alluvial floodplains, fluvial environments and estuarine/intertidal zones. Using palaeo-environmental proxy indicators, such as pollen and diatoms, we reconstruct past environments. Our specialists also use a range of sedimentological techniques.”

These techniques don’t answer every questions, but coupled with expertise and interdisciplinary research, enables us to see further, and deeper than previousl.  The role of archaeology and geoarchaeology in hidden hydrology is vital, as shown above. While we often rely on maps, photos, sketches, and written histories to reconstruct places,


HEADER:  Artist’s reconstruction of a cold climate, braided river, such as the Late Glacial Thames (artist Faith Vardy) – via

A recent article in the Denver Post “Denver accelerates “daylighting” of lost waterways, “undoing history” with decades-long re-engineering effort” discusses some exciting new work on restoring hidden hydrology and “Re-opening of buried waterways” in the area to manage stormwater runoff and create habitat.  The context:

“Old Denver pulsed with H2O, water that snaked through the creeks and irrigation canals crisscrossing Colorado’s high prairie before 150 years of urban development buried most of them or forced them into pipes.”

A similar story to many cities across the globe, “…developers focused on filling in creeks to make way for the construction of railroads, streets, smelters and housing — all laid out across a grid imposed on the natural landscape.”  This can be remedied today “…by reconstructing the urban landscape where possible, they’ll slow down water, filter it through vegetation to remove contaminants, control storm runoff and nourish greenery to help residents endure the climate shift toward droughts and rising temperatures.”

DENVER, CO – AUGUST 27: Newly planted grasses grow along Montclair Creek on August 27, 2018 in Denver, Colorado. The City of Denver is working on restoring the creek to help with future flooding. (Photo by RJ Sangosti/The Denver Post)

It’s heartening to see this large of a paradigm shift, and engineers, such as Bruce Uhernik, whom quoted saying:

“We’re just trying to take back that space and make waterways more natural and more beautiful. Why would people not want something to be more natural? This is being responsible — not just to what the city and people need, but to the environment’s needs. Birds. Fish. Trees that should be growing along these corridors. All these work in unison. If you break the chain, things fall off course.”

I appreciate some of the language, but the term “undoing history” is a bit strange to me as I always think of projects like this, in any form, as redoing history.  I guess it’s your take on what is history: the original pre-development condition that needs to be restored, or the interventions and filling as the history that needs undoing.  As mentioned, there’s plenty of history as “Historic Denver maps from the late 1800s show multiple irrigation canals and curving dotted lines denoting unnamed waterways, including a creek that flows through the Montclair Basin from Fairmount Cemetery toward north Denver industrial areas where smelting and rendering plants were located along the South Platte.”  

Either way, it’s a cool project, and has some unique components and context, much of which can be found in the Denver Public Works ‘Green Infrastructure Implementation Strategy‘, a document broad interventions for stormwater and habitat.  The prevalence of creeks is seen in the map of Recieving Waters (page 7) shows that while there are a number of urban creeks, they are impacted by residential, commercial, and industrial development throughout the region,

 

A series of maps in the report outlines pollutants of concern like Fecal bacteria and E.coli, Total Suspended Solids (TSS), Nitrogen, Phosphorous.  This map (page 21) shows subbasin level designations of Nitrogen, which is elevated by human activity, and can lead to algae blooms, and issues with aquatic species.

A focus on the urban core includes the Platte to Park Hill (Part of area 20 above (City Park/Park Hill), which integrates a number of systems.  As mentioned in the report:  “Stormwater Systems is taking a
comprehensive green infrastructure approach to better protecting people and property against fooding while improving water quality and enhancing public spaces.  Four projects are part of the Platte to Park Hill… Collectively, the  four coordinated projects will increase neighborhood connectively, add new park and recreation spaces, provide critical food protection, and improve water quality.” (page 54)  The Globeville Landing Outfall project is one of these segments, as part of the strategy, using open channel design, which “…will help clean storm water naturally when possible and will move the water to its ultimate destination, the South Platte River.”  A rendering of the plan:

The 39th Avenue Greenway (also seen in the header) also includes open channels for flood control and storm events.  The opportunity to layer community function with these facilities is key, as they are “…designed using a community-focused approach to provide the following benefits in addition to flood protection… “ which includes new open space, bike/walking trails, and more.  A rendering shows this integration.

An additional article from the Denver Channel provides a bit more perspective in video form on the Montclair Creek Project, including the “gray to green” approach “correcting past mistakes” focusing on the daylighted river weaving through a golf course and some more urban parts of the City, along with a greenway as mentioned above prior to outlet into the South Platte River.  The funds for the project, which were not insubtantial at $300 million, were voter-approved, with “daylighting of old waterways that were forced into pipes and buried during the industrial revolution in favor or streets, railroads and homes.”  


HEADER: Image of the 39th Avenue Greenway and Open Channel  – via the ‘Green Infrastructure Implementation Strategy‘ (page 55)

There’s a plethora of early maps of Portland, many of which I’ve recently included and cataloged here for reference.  One of those maps I’d never seen before recently, oddly, is this sketch-map made by William Clark (yes, he of Lewis & Clark expedition fame) from April 3, 1806, featuring a sketch of the Multnomah River, “given by several different Tribes of Indians near its entrance into the Columbia.”  The original link comes from this Oregon Encyclopedia article on the Wapato (Wappato) Valley Indians, found whilst researching native settlements in Portland, notably those around the important confluence of the Willamette and Columbia but getting a feel for pre-settlement use of waterways. The map is found in Volume Four of the Original Journals of the Lewis and Clark Expedition, 1804-1806, which constitutes the return trip of the Corps of Discovery from Fort Clatsop on the Oregon Coast back towards the east.  The entry and fold-out map includes a remarkable amount of information including natural and hydrological features, as well as references to many of the tribes as alluded to in the title.

It’s amazing to see the detail of the map and density of information, in what I assume was field drawn, probably in a canoe, fending off bears while simultaneously collecting plant samples.  I jest, but I’m constantly amazed at the ability of early explorers to represent places quickly and with much    For me, at least, it was much easier to conceptualize graphically if you rotate the map so north is facing up, so the subsequent enlargements flip this over.  This enlarged view shows the key features at the confluence, perhaps not drawn to scale, but remarkably accurate, including to the east, both the Washougal River (noted as Teal) and the Sandy River (noted as the Quick Sand). There are also notes on the various encampments on river banks, such as the Nechacolee and Nechacokee around Blue Lake in Portland on the south bank, Shoto up around modern day Vancouver Lake to the north and many more smaller encampments of the local Multnomah and Kathlamet tribes. To the west, around Wappato Island (modern day Sauvie Island) which was home to Multnomah, Clannahqueh, Cathlahcommahtup and others on Sauvie Island on the Columbia River, and around the other side of the island, known as the Multnomah Channel. See this additional post from the Oregon Encyclopedia for Lewis & Clark’s estimate of the Portland Basin Chinookian Village tribal populations here as well for more detail.

The same zone taken from a Google Earth image shows the general location of and features. The fidelity of the geography is a bit off (it’s a sketch map) but it’s all there.

Further south, the geography is a bit more sparse, but does include the upriver span of the Willamette (called here the ‘Multnomah River’) and it’s connection to the Clackamas River (heading east) including encampments of Clackamas along that river, and perhaps mis-estimating a bit how far away Mt. Jefferson actually was (see below)… and ‘The Falls’ which denotes Willamette Falls, which was an important settlements along this important confluence,  and Charcowah, and Cushhooks near the Falls….

The same view of current day area, again with a bit of misalignment of the rivers, which probably comes from the map being adapted from a drawing done by a local tribal elder, but the general features there.

The text supplements the map somewhat, with stories of meeting a group of Shah-ha-la Nation and showing them the Multnomah:

“we readily prevailed on them to give us a sketch of this river which they drew on a Mat with a coal, it appeared that this river which they call Mult-nó-mah discharged itself behind the Island we call the image canoe island, as we had left this island to the south in decending & assending the river we had never seen it.  they informed us that it was a large river and runs a considerable distance to the south between the Mountains.”

Clark takes a party to explore, and encounters huts from various tribes, along with harvesting of wappato and roots via canoes along the rivers, and found the hidden entrance to the Willamette (which he refers to as the Multnomah River, along with the tribes on Wappato Island and noted the depth of the.  He mentions that he “…can plainly see Mt. Jefferson” which may allude to it’s proximity on the one map.  As he continued to explore he mentions being “satisfyed of the size and magnitude of this great river which must water that vast tract of Country between the western range of mountains and those on the sea coast and as far S. as the Waters of Callifonia…” which if not totally true, does allude to the size of the Willamette drainage in at least draining a fair portion of NW Oregon.  He continues by visiting a long house, and learns the constant refrain of deaths from small pox and starvation. He asks for a map of the area and the people from one of the elders.  “I provailed on an old man to draw me a sketch of the Multnomar River and give me the names of the nations resideing on it which he readiliy done, and gave me the names of 4 nations who reside on this river two of them very noumerous. The first is Clark-a-mus nation reside on a small river… the 2.d is the Cush-hooks who reside on the NE side below the falls.”

They note the entrance to the Multnomah river being “142 miles up the Columbia river” from the Pacific, include the sketched map, and then are off, up-river, continuing eastward.

An excerpt of the journal, the specific passage of which is available via this Oregon Encyclopedia post here as well.

A recent story picked up by multiple sources focused on the potential for hidden hydrological systems to provide heat and cut carbon emissions through tapping into underground lost rivers.  The crux of the argument is that heat pumps could extract heat from these now piped subterranean waterways, and this heat could be used for buildings and other uses, offering an alternative power option for London.  The Guardian offered the potential for heat to “cut capital’s emissions”, and the Times and The Londonist echoed this, focusing on Buckingham Palace as a visible example for the potential for heating buildings.   Mother Nature Network and Earth.com a took a slightly different slant, focusing on helping curb carbon emissions, similar to the coverage from the Daily Mail about using heat from underground rivers to “tackle climate change”.

The specifics come from a group called 10:10 Climate Action, and a recent report highlights ‘Heat seeking in London’s lost rivers’, and looking at the variety of now-buried rivers as a source of power:

“But what if we could use them to power our city once again? Through the magic of heat pumps, London’s lost rivers could provide low cost, low carbon heating and cooling to the buildings above. They could help us solve the big challenge of decarbonising heat.  There’s huge potential for London’s lost rivers to provide clean, efficient and reliable heating for the city – tackling climate change and air pollution. And of course the same technology can be used in other underground waterways like sewers in towns and cities across the country.”

 

y for heat pumps to transfer heat from one place (the subterranean pipes) to another, specifically buildings or other areas via refrigerant, where it is compressed to form heat at the top of the loop, and then expanded to cool down and capture more of the heat.  A primer on heat pumps, as well as a video showing how heat pumps work also helps explain the concept, along with this diagram.

This is already happening in some areas, including Borders College in Scotland, tapping into local wastewater, and the State Ministry Building in Stuttgart, Germany, which is tapping into flow from the Nesenbach, a buried river.  A map extracted from the report (image below) shows a number of the potential sites in London, including The Effra, Stamford Brook, The Tyburn, and the Fleet, all of which have potential sites for the use of these technologies.  Specific places include Buckingham Palace (mentioned in a few of the articles above), which would tap the Tyburn, Hammersmith Town Hall which flows above Stamford Brook, and other buildings like schools and site elements like heated swimming pools, which is currently being done in Paris.  [click to enlarge map below]

A video from 10:10 explains this in a bit more detail, showing an example of a London pub sits atop a lost river and uses this heat pump technology and for it’s heating and cooling.

There’s questions on the cost-benefit, and each of these systems would require some infrastructure to be viable, however it’s pretty exciting to consider the potential of these systems to contribute to energy savings and reduction of carbon emissions, giving back some of their benefits to the city, even while still being buried underground.  I’m sure we’ll hear more about this process in cities around the globe, all of which could utilize similar techniques, as we search for expanded tools to battle climate change and rising energy costs.


HEADER: Image of the now subterranean mouth of the Fleet, via The Guardian

A simple yet evocative project, Below the Surface is a catalog of objects found when a canal was drained in Amsterdam, creating a longitudinal timeline spanning from modern day to prehistory.  From the site:  “Urban histories can be told in a thousand ways. The archaeological research project of the North/South metro line lends the River Amstel a voice in the historical portrayal of Amsterdam. The Amstel was once the vital artery, the central axis, of the city. Along the banks of the Amstel, at its mouth in the IJ, a small trading port originated about 800 years ago. At Damrak and Rokin in the city centre, archaeologists had a chance to physically access the riverbed, thanks to the excavations for the massive infrastructure project of the North/South metro line between 2003 and 2012.”

The immensity of artifacts found in this hidden hydrology is amazing, and offer a rare chance to look below the surface (as opposed to underwater explorations, which has a range of limitations).  As mentioned:

“Rivers in cities are unlikely archaeological sites. It is not often that a riverbed, let alone one in the middle of a city, is pumped dry and can be systematically examined. The excavations in the Amstel yielded a deluge of finds, some 700,000 in all: a vast array of objects, some broken, some whole, all jumbled together.

The historical context spans a modern timeline going back many centuries, and the evolution of the site were important and provide context for what was found.  For the Rokin site, seen below, the area: “…served as an inland harbour for boats transporting goods and people from the hinterland. Both banks were densely developed with housing, workshops, shops and institutions, among which the Nieuwezijds Chapel (1347). The local urban fabric was constantly changing as major spatial interventions were implemented.”  

The site gives a detailed overview of the project and the archaeological challenges and opportunities, which include two sites, the Rokin and the Amstel. “For purposes of research, there were two intertwining strands: the city and the landscape. These revolved around the origin and history of Amsterdam. Finds from the river, consisting of (the remains of) ceramic, bone or metal man-made objects (artefacts), afford an insight into the material culture of the city. Ultimately, archaeological remains reflect the everyday activities of humans, in this case, of the inhabitants of Amsterdam and its visitors. As such, they are invaluable in the reconstruction of the historical picture of Amsterdam. The value of material remains as sources of urban history lies largely in their connection with the topographical structure of the city. Hence, the vital importance of the link between the deposits and their spatial origin in urban archaeology.”

The concept of streambed archaeology is well documented also, including the process of retrieval is aided somewhat by their submersion, as mentioned: “Another factor that makes streambed sites unique is their tendency to remain intact on account of the inaccessibility of the sunken objects. Once they had fallen in the water it was not easy to get them out. “  There are specific water focused objects, as well as giving clues to what was adjacent to the waterways: “Quite apart from the physical aspect of archaeological material sinking down in water, underwater depositions differ from deposits on land in the diverse origin and generally mixed nature of the finds. They are primarily associated with shipping activities and vary from items that have fallen overboard to complete shipwrecks and parts of ships. Archaeological remains can also be connected with activities ashore. As such, they can often be linked to objects associated with a building or structure, workshop or installation along the bank.”

The visuals of what has been found is provided in a grid, following chronological order, in order to sort from modern to ancient.  The recognizable debris from the modern era, such as credit cards in the 2000s, jewelry and china from the 1650s, pottery from the 1450s, and even fossiles and shells from early prehistory (listed as -119000).  A temporal snapshot of evolution, and an indication that, among their many urban uses, urban water bodies are a repository for our shared archaeological history.

xxx

 

Beyond this, each individual object is cataloged individually, such as this pocket knife.

There’s also a print version, called Stuff, which is available:

The cultural relevance of this detailed exploration hints at an expansive role of waterways in the urban context as containers for memories and, perhaps a time capsule for objects that can trace our lineage over millennia.


HEADER:   Excavation site at Ferdinand Bolstraat station, the cross-section shows the top of the Pleistocene (10,000 B.C.)

The New York Times did a recent story on How the Ice Age Shaped New York with a tagline Long ago, the region lay under an ice sheet thousands of feet thick. It terminated abruptly in what are now the boroughs, leaving the city with a unique landscape.”  This resonated with me and reminded me of posts about Minnesota’s Lake Agassiz, as well as the Waterlines presentation last year by Dr. Stan Chernicoff on Seattle’s own geological history and how the ice age covered the city with a deep layer of ice ground away over time and as it melted 10-20,000 years ago, influenced and left many traces on cities.

New York City experienced similar issues, with a two-mile thick ice layer forming over two million years back, covering the area region encompassing much of the city and all of Manhattan, with the terminal moraine reaching the zone bisecting parts of Staten Island and Long Island, until warming and retreat 18,000 years ago.

The story of many areas is the same, the depth and weight of ice shifting bedrock, and creating waterways, kettle ponds and lakes, as well as retreat leaving glacial erratics and other rubble strewn through the zones.  However it’s more distinct in New York City, as pointed out in the article:  “While the line of glacial debris across the northern United States is often poorly delineated, the hilly ridge around New York City tends to be quite prominent. Its maximum height is roughly 200 feet, about that of a tall apartment building.”

The ridges and hills determined where people settled, as they avoided these areas and found flatter ground, and I remember the specific outcrops left in place in Central Park as features, but perhaps also to avoid having to blast or remove them. (see header image above)  The article mentions that many place names are derived from this rises, appended with Hills, Heights, and Slope and also its usage in local building materials.  The proximity of the terminal moraine to New York City is unique, but that glacial history has been forgotten over time.  As mentioned:

“Despite the ridge’s prominence and early allure for scientists, it turned out to be no rival for skyscrapers and urban distractions. The moraine that shaped the city was all but forgotten. “Clearly, it’s not on the radar,” said David E. Seidemann, a professor of geology at Brooklyn College. “The educational system here doesn’t emphasize earth science. And there’s so much else to do. I’ll go to a Yankees game over geology any day.”

But the hidden remnants paint a fascinating picture, capture by geologist and environmental educator from the American Museum of Natural History, Sidney Horenstein, who also does tours of these phenomena.  He found documents showing that geologists working in the 1800s found in terms of the variation of hill to flatland geology: “Ridges, mountains and even flatlands are typically rooted in rocky strata, such as the bedrock that underlies Manhattan and makes it ideal for erecting skyscrapers. But early investigators found the hilly ridges to be composed of clay, silt, sand, pebbles, cobbles and boulders, all jumbled up together.”

The walk through reports (such as the fascinating Natural History of New York published in 1842) established a chronology of more focused work on things like history of glacial floods, and fills in gaps on geological processes, even showing the emergence of terms to describe processes, like ‘Ice Age’ which was starting to be more widely used in the 1880s.

A 1902 USGS large-format map provided some spatial information as well

The maps used colors to show variations of geology amidst the emerging city grid, and identified the terminal ridge. As the article points out:

“At first, the city used the stony ridge for woodlots and rain catchments. Slowly, the uses expanded to reservoirs, recreational areas and, in time, neighborhoods in which buildings and houses were built on strong footings and foundations for stability.  Today, despite the wide development of the ridge’s lower slopes, a Google Earth view of New York City — a composite of images from April, June and September — shows the glacial relic as an intermittent band of green.”

A larger image of one of the maps  from the folio is seen below, via NYC99 gives an indication of the rich data available – click to enlarge (image source from Texas A&M Library).

Similar to the Missoula Floods that broke through a massive ice dam and carved out the Columbia River basin, New York also had a flood termed ‘biblical’, as glacial retreat happened around 13,000 years ago, where a “... towering wave of destruction crashed down through the Hudson gorge and proceeded to smash the southern end of the local moraine to smithereens.”

It’s interesting to draw parallels between how the glacial impacts are similar on the east and west coasts, but also how they differ due to variations of geology and topography.  The hidden history isn’t just hydrology, but a combination of physical and biological processes working in tandem, over millennia. We’ve done much to erase and obscure, but traces remain, indications of these long and large processes are tucked away under our feet, waiting to attract our gaze.

“…millions of people live on or near the glacial ridge. In all, it runs for roughly 30 miles beneath New York City. Invisibly, it links three boroughs, offering mute testimony to the power of vanished ice.”

 


HEADER:  Umpire Rock in Central Park – this and all other images, unless noted, via NY Times  

Some news on the project front, which partially explains the slow output on this end lately in terms of hidden hydrology updates:  I’m moving from Seattle back to Portland.  As regular readers know, the project origins are firmly rooted in Portland, including plenty of documentation and expansion of ideas around Tanner Springs Creek (seen below), and maybe I will finally track down one of those elusive ‘I Kayaked Tanner Creek‘ t-shirts of legend.  Anyway, happy to announce this news, and Portland folks, let me know if you’re interested in some exploring in coming months.

There’s also a plethora of other areas to explore, and also to compare and contrast the unique dichotomy of Portland as a river city and Seattle as more of a ocean & lake city, and what that means/meant for development.  On that note, one item I’ve not announced is some of the work figuring out the best format for a Hidden Hydrology Atlas that will span both Seattle and Portland – so stay tuned for more of this as technology and funding aligns.  For now you can see the early version of the online example of interactive maps I’m testing out using a combination of Mapbox and my GIS database of information.  Early days, but the potential is there, and it will expand into something more comprehensive and multi-media.

While I did get to explore a number of Seattle hidden streams, there’s so much more to do and lots to document for Ravenna, Yesler, and Green Lake, and hopefully coming back up to do more investigations.  In the interim, one of my explorations I documented here in Seattle from last summer, Licton Springs, was the departure point for an essay I wrote recently for The Nature of Cities that was just published this week. Read ‘Map and Explore: Hidden Hydrology’ for some thoughts on exploring our places and connecting with our culture, geography and ecology.

So, stay tuned as projects, posts, and explorations will all pick up over the summer months.  And as always, thanks for reading.  See you all in Portland soon.

-Jason

Today I picked up a copy of Richard Sennett’s new book ‘Building and Dwelling: Ethics for the City’. (Farrar, Straus and Giroux, April 2018).   From the website: “Building and Dwelling is the definitive statement on cities by the renowned public intellectual Richard Sennett. In this sweeping work, he traces the anguished relation between how cities are built and how people live in them, from ancient Athens to twenty-first-century Shanghai. He shows how Paris, Barcelona, and New York City assumed their modern forms; rethinks the reputations of Jane Jacobs, Lewis Mumford, and others; and takes us on a tour of emblematic contemporary locations, from the backstreets of Medellín, Colombia, to the Google headquarters in Manhattan. Through it all, he laments that the “closed city”—segregated, regimented, and controlled—has spread from the global North to the exploding urban agglomerations of the global South. As an alternative, he argues for the “open city,” where citizens actively hash out their differences and planners experiment with urban forms that make it easier for residents to cope. Rich with arguments that speak directly to our moment—a time when more humans live in urban spaces than ever before—Building and Dwelling draws on Sennett’s deep learning and intimate engagement with city life to form a bold and original vision for the future of cities.”

While the book aims to hit on a much broader range of topics that we typically cover, the first part resonated on the Hidden Hydrology front with some interesting analysis of the work of that prominent figure in the history, that of Joseph Bazalgette.  For a bit of a primer to the unfamiliar, check out this good post about Bazalgette as “Scientist of the Day” and also behold his amazing mustache below.

Sennett discusses this in Chapter 2, which looks at the evolution of cities in the mid-19th Century, which was a turning point for urbanization that was leading to overcrowding, pollution, and disease, many issues of which had been somewhat unprecedented in modern cities.  As he mentions, “Plague had always been a danger in cities — the Black Death wiped out a third of Europe in the late Middle Ages. As early modern cities became bigger and denser — and so more shit-and-urine filled — they became fertile gardens to feed rats and rat-borne disease.” (21)

Sennett mentions that the first actors in combating this trend were not doctors, but engineers.  Working to improve the quality of urban life, he mentions the ideas around paving of streets as a way to encourage cleaner urban areas, as well as the development of the pissoir  a simple yet seemingly necessary advance in urban sanitation.   The effect of these improvements were functional, but as Sennett points out, the ripple into more livable cities was a unique cross benefit.  As quoted:

“… a knock-on effect of removing shit and urine from the street was that it made the outdoors more usable as social space; the huge outdoor cafe fronting a boulevard was the sanitary engineer’s gift urban civilization.” (23)

The idea that engineering was the major driver for public health in the 19th century, and that it had the residual impact of creating better cities, was often “accidential and unintentional” as Sennett mentions, but often it did come with a direct purpose.  This action-oriented and experimental approach was best embodied by Joseph Bazalgette, and his engineers, working incrementally and often experimentally, invented technologies through trial-and-error:

“The engineers working for Joseph Bazalgette, for instance, when building London’s sewers in the 1850s to 1860s, invented such technology as solid-waste screens in the course of fitting sections of piping together, experimenting with several different filter designs, rather than knowing right away which size to use.  Bazalgette was what to do overall: the realm of the sewer — the realm of Les Miserables — had to be made into a network of pipes mirroring the streets above.”  (24)

The concept of experimentation was an interesting point, as he “often built sewers with pipes larger in diameter than seemed to be needed, saying that planning could not predict future needs,” (24) and as Sennett contends, “One of the truly admirable aspects of Bazalgette’s character is that he exuded Victorian confidence without claiming that he knew exactly what he was doing, believing only that he would get it right in the end.  This is more largely true of civil engineers in the city at the time; their technical knowledge was open-ended.” (25)

The simplified version of the Bazalgette plan shows the series of cross connected interceptors that are all funnelling pollution away from the Thames.

The other element brought up, which deserves more thinking is the “…experimental process required the engineer-urbanist to develop new visual tools,” and that “the messy compound forms along a dense, disordered street requires a different means of representation” (24).

Classical techniques such as plan and section worked to build the infrastructure, as seen above, however they failed to work to communicate concepts as “the infrastructures the engineers were building below ground were invisible” (25).

An image I did find that hints at these new techniques, via the Linda Hall Library, shows the use of cutaway section-perspective to outline the multiple layers of surface and subsurface systems working in tandem.

While I don’t purely think that Bazalgette was motivated by anything beyond doing the right thing, I think the idea of ‘what was the right thing?’ is perhaps the bigger question.  The fact that this ‘modernization’ is often times purely reflected as only a positive move, rubs me the wrong way, as it discounts all the other impacts.  Maybe there was a lack of understanding or lack of imagination at the time, and that burying urban rivers, creeks and streams was the only means available to solve the issues of pestilence, smells, and disease.

The implications, in London, but also world-wide, as these approaches were copies and applied often elsewhere around the globe, had such massive ecological consequences on the hydrology of cities that is, without hyperbole, impossible to reverse. A river or creek sacrificed into a pipe is not the same as a more holistic plan understood and valued the myriad benefits of urban streams and saved these waterways while protecting public health. Sennett’s take that the engineers, as mentioned in the photo caption “Joseph Bazalgette, the finest engineering of the modern city…” (Fig. 1) were saviors and their focus on public health saved many lives is indisputable.  But the cult of this benefit misleads about the cost, and it would be great to counterpoint this message with the worldwide implications of what he and many future engineers wrought on the urban ecology everywhere.

 


HEADER:  London Sewer Plan Map from 1882 – via Wikipedia 

An email from a reader of the site posed a few interesting questions about the two small lakes in the northern sections of Seattle, specifically discussing the current and historical outflows of these lakes.  I’ve discussed the small lakes in brief here, related maps of their bathymetry and tangentially in the context of Licton Springs. However, this was a good instigation to to focus on some more specifics of these urban water bodies.  I will refrain from my tendency to write another way-too-long post (of which this will inevitably turn into) and parcel this out in a few shorter ones, the first focusing on drainage questions (of which these are all connected) and then individual posts on Haller Lake, Bitter Lake, and Green Lake, as they are important parts of the hydrological history of Seattle.

To understand the overall configuration of water in Seattle, I did find this document by Seattle Public Utilities (SPU) titled ‘City of Seattle State of the Waters 2007‘. The first volume covers Seattle Watercourses, (which we will probably return to in the future), and in particular for our purposes here we look to Volume II: Seattle Small Lakes’  (both links above go to the PDFs – as I couldn’t find a page with a direct link) and it sounds like a great resource in need of an update.

For some general contents, a bit on lakes in general and their outfalls, from Vol. II, p.3:  “Lakes receive inflow from their surrounding watersheds through rivers, watercourses, overland and subsurface flow, and — in developed areas — from drainage pipes. Water typically exists a lake through a watercourse or river, although the outflows of most lakes in Seattle have been channeled into constructed drainage systems.”

HISTORIC DRAINAGE

In general, all three lakes are formed from Vashon glaciation, and as I mentioned previously, per geologist Stan Chernicoff, both Bitter and Haller lakes would be considered true kettle lakes, and Green Lake a hybrid, although still formed by glaciation.  The 1850s map locates the three Lakes, all of which are in the north portion of Seattle, but doesn’t offer too much in terms of drainage direction, aside from implying proximity between Thornton Creek drainage for Haller Lake, and Bitter Lake likely draining west due to proximity, neither show a visible outfall creek.

Green Lake it’s more obvious, with multiple inflows, including Licton Springs Creek, and the very distinct outflow that drains through Ravenna Creek southeast into Union Bay.

The 1894 USGS map offers us the aid of topography, along with a bit more more comprehensive creek coverage. Bitter Lake hints at the possibility of outfalls either direction, heading to the northwest down to ravines that skirt The Highlands and the Seattle Golf Club and outlet near Spring Beach, and also draining southeast towards a seasonal drainage. Haller Lake (titled Welsh Lake on the map) also has no visible outfall as well, but adjacent creeks that are part of Thornton Creek drainage nearby, and a wetland area to the south make me infer that these  would be like to be the natural drainage course of the lake.

Green Lake’s hydrology is a lot simpler to discern, with the similar inputs and outputs via the Ravenna outlet to the wetland zones near University Village and outlets into Union Bay.

TWO ALTERNATIVE THEORIES ON HISTORICAL DRAINAGE

One part I’ve always been a bit skeptical about in the USGS map is the location and extent of the drainage from Thornton Creek that looks to curve way west and intercept any south flow from the Bitter and Haller Lakes and direct it to the east to the larger Thornton Creek Basin.  Licton Springs Creek also flows south, and is in reality much further north than shown on maps, and the interface between the two basins if filled with springs and wetlands, so it’s likely there could have been some disconnect between what was there flowing south, and what was mapped flowing east.  However,  Alternative 1 uses the basis of the map as the correct flowline, so shows both Bitter Lake and Haller Lake draining towards a seasonal creek and wetland that exists in the South Branch of Thornton Creek, and a smaller drainage picking up Licton Springs Creek draining into Green Lake.  This mapped, overlaid on the 1894 map, shows an option for the lakes draining east, into Lake Washington. Dashed lines, for reference, are really basic watershed delineations, and the arrows show flow from lakes.

My gut is that both lakes flowed into Green Lake, via Licton Springs Creek, and then continued out to Ravenna.  Alternative 2 looks at a version of this where there is more of a distinct ridgeline separation between the Thornton Creek Basin and the drainage that flows north south, and that the survey misinterpreted the flowline that heads towards the east due to the aforementioned springs and wetlands.  The fact that the Licton Springs Creek is much further north than mapped, makes me posit that the upper lakes drained to this transfer point, and that instead of falling east, the flows kept going south into Green Lake, via the Licton Springs. Overlaid on the modern topography gives a bit of context to this configuration.

Both of these options are plausible, and the current outflows of the lakes (seen below) support this, with Bitter Lake draining to the Southeast and Haller Lake draining West.  This at least gives us the indication that these both flowed to the low north/south valley (where current Highway 99/Aurora Avenue runs), however, where they go after is still a bit of a mystery. My follow-up plan is to look at some Lidar or a DEM to provide a much clearer picture of the flowlines and ridgelines, which we can assume, much like the current topo, is mostly similar to its predevelopment configurations (i.e. places in Seattle where we didn’t move hills).  This will go beyond this back of the napkin approach above and see if that higher degree of detail unlocks any new info.

CURRENT DRAINAGE
While it’s hard to determine the exact nature of pre-development drainage on these lakes, we can infer much from these historic documents and topography.  The current system is more clear, although not visibly inherent due to the modernization and piping of drainage through large intercepter sewers – in this case the Densmore Avenue Drainage System, which runs north/south around the low flowline at Aurora Avenue (Highway 99).

The first hint of the split of drainage is in the State of the Waters, where both Bitter Lake and Haller Lake fall outside of their adjacent drainages going west to Piper’s Creek and east to Thornton Creek.  Figure 1 from the report shows a narrow band that is bisected by this linear north south zone, with both creeks located inside the boundary.

A search for the nature of this basin configuration is somewhat frustrating, mostly as it seems to be specifically not related to a creek so isn’t referenced as a watershed in the same way.  The SPU site on Urban Watersheds breaks down the city into four distinct areas of drainage, including the Puget Sound, Lake Washington, and the Duwamish River, as well as this uniquely land-locked zone we’re focused on, known as the Ship Canal/Lake Union basin

This is subdivided into some smaller sub-basins,including the Ship Canal Basin, the South Lake Union, and our zone, the North Lake Union Basin, which stretches up to the northern lakes, in that same narrow band, encompassing their drainages, then around Green Lake, and south to the interface with Lake Union.

The specific acrobatics that the Densmore Basin does to get down to Lake Union is hinted at but there’s not a lot of great maps, in particular the last section which .  This excerpt from the Seattle Comprehensive Plan Update Draft EIS from May 4, 2015 shows the ‘capacity constrained’ condition. but does highlight the basin and it’s

I dug a bit more and found another mystifyingly badly interfaced GIS portal, this time Drainage Basins layer from City of Seattle, embedded below.  Again, need to download the data and have a bit more freedom to sort it out in order to display it in a better way, but you get the idea from this map (especially if you zoom in on the areas below Green Lake, and can see the basin outline snaking in a thin, gerrymandered strip beside I-5.

 

The lakes themselves fit within the infrastructure systems, as seen below.  The City of Seattle Water and Sewer Map , which I thought would be helpful but really isn’t because you have to zoom way in to show pipes and so lose context, so it  doesn’t clearly articulate the drainage system elements enough to isolate (i included a few screenshots), so probably need to get some GIS files to draw these and separate mains, branches, etc. to isolate systems, but the narratives are pretty clear in explaining the outfall scenarios.

Haller Lake, which is around 15 acres of drainage, and has a maximum depth of 36 feet, get’s inputs from adjacent residential drainage areas (280 acre drainage), now drains via the Densmore system, as mentioned in State of the Waters, Vol II, the lake “…discharges through an outlet control structure on the western side of the lake, eventually draining to Lake Union via the Densmore storm drain system.”

Bitter Lake, measures 18.4 acres with a max depth of 31 feet, draining a smaller area (159 acre drainage). This lake is also being drained into the Densmore system, from the State of the Waters, Vol II, page 25: “At its southeastern end, Bitter Lake drains through a piped outlet that runs through a series of small ditches and culverts before entering the Densmore storm drain system on Aurora Avenue North.  The Densmore system is equipped with a low-flow bypass, which conveys runoff directly to Lake Union. Under high-flow conditions, runoff passes through Green Lake before discharging to Lake Union.”

Green Lake, has a surface area of 259 acres, and a shallow depth, maxing out at around 30 feet, drains a basin of 1875 acres of surrounding area, as well as getting inputs from the Densmore system, as mentioned above.  Alas, it now no longer drains into Ravenna Creek, but is diverted, per the State of the Waters, Vol II, and“now discharges to Lake Union through a single outlet located near Meridian Avenue North.  In the past, Green Lake also discharged to the combined sewer system via a number of outlets around the lake. However, these outlets were recently blocked and now are used by Seattle Parks and Recreation only during rainstorms of long duration when the Meridian Avenue North outlet is not adequate to maintain water levels in Green lake.”

 


HEADER: Haller Lake from above – via Windemere