There are some that shape Seattle, including Lake Washington to the east (see above header image), a massive 21,500 acres of lake area and a max depth of 214 feet, draining a watershed of over 550 square miles and defines the entire inland edge of the city.  In the medium size category is centrally located Lake Union, (below) which encompasses 580 acres, a max depth of 50 ft, and a similarly larger watershed.  These, along with the Salish Sea to the west, and the Ship Canal and locks, literally form the hourglass shape of the City of Seattle and make up much of the story of the city in terms of water.

Nautical charts aside, we will have plenty more to come on these in terms of history and form, as well as some new efforts that have unlocked some mysteries hidden in their depths.  For now, In addition to these large lakes, there are a number of small lakes that dot the landscape, remnants of the glacial action, namely in the form of kettle ponds. King County has a site for Lakes Data and Descriptions, which includes both, but of particular interest is the page for Small Lakes Data and Info, which allows access to information on these lake, including some simple yet compelling bathymetric maps.   Green Lake falls into the small lake category (and also has been plagued with water quality issues.  The bathymetry shows the current shoreline, which has a lake surface of 259 acres with a contributing watershed (although no contributing streams anymore) of 1875 acres.

For a slightly different visual,this 1938 W.P.A Sanitary Survey map (via the Seattle Municipal Archives page) shows a color coded look “Showing Depth Contours of Green Lake as of 1936”.

Those familiar with the story will know that the shoreline of the lake was changed a bit around the turn of the 20th century, and the addition of the waterfowl named island by said WPA also was not an original, but more on the historic manipulation of the shoreline of Green Lake at a future date.

For now, another interesting resource on the King County Lake site charting of various lake metrics, including water quality.  As I mentioned, water quality issues, mostly in the form of toxic algae growth, have been problematic in Green Lake, with a peak issue in 2013 and a spike in 2016   Some historical data shows the situation in 2016, which shows a spike in Chlorphyll-a, which is an indicator of algae growth, and subsequent nutrient and temperature charts.

The smaller lakes in North Seattle also appear, including the smallest (yet deepest) Haller Lake, which has a surface are of 15 acres, with a max depth of 36 feet.

Bitter Lake has a surface area of 19 acres with a depth up to 31 feet.



Both are probably similar in size today as they were in the 1800s, based on the historical maps.  The land uses and while the land use has changed, also probably have similar catchment zones.  Maps on the site outline these watersheds, for instance the 331 acre drainage of the lake.  As mentioned on the site: “This map shows the area of the watershed relative to the area of the lake. Generally speaking, the larger a watershed is relative to a lake, the greater the influence land use practices on lake water quality.”

An interesting tidbit on this was discovering the amazing Lakes of Washington by Ernest E. Walcott published in the early 1960s which was the basis for much of the bathymetric info included on the King County site and other resources.  I’ll expand on at a later date, but in that vein, while outside of the city proper, the range of bathymetric maps, so I snipped a few pages out of this document, which includes lakes in King County that are part of the Lake Stewardship Program – just for a flavor of different lake forms in comparison (at least formally, as they do vary in scale) – all of which are derived from the work of Wolcott.

And if you still need your Lake Washington bathymetry fix, one I did find, for the more artistic (or looking for a gift for that special map nerd) are these fun wood fun maps (found amongst other local and national water bodies) sold on Etsy by ‘Beneath the Sail’


HEADER: Nautical Chart of Lake Washington

The final installment of books looking at London hidden hydrology is Walking on Water: London’s Hidden Rivers Revealed, by Stephen Myers.  As part of the parade of books on the topic published in 2011, this takes a very different approach than the tour/photo guides of Talling and Bolton, reflecting Myers’ background as an engineer.  If you’ve checked out the previous post on the Barton book, you’ll recognize some of this similar analysis, as the 2016 3rd Edition of ‘The Lost Rivers of London’ includes Myers as a co-author, and seems a hybrid of this book and Barton’s earlier versions.

On that note, Myers approaches the project from that engineering perspective, and its loaded with info.  A blurb from Amazon“London’s hidden – or lost – rivers are a source of fascination. This book concentrates on seven North London rivers – the Fleet, the Walbrook, the Tyburn, the Westbourne, Counter’s Creek, Stamford Brook and the Black Ditch. The author, a professional water engineer, describes their sources and traces their individual histories, setting out their influence on the development of London and their use and abuse by society, eventually leading to their disappearance. The original watercourses of each of the seven rivers are shown on London street maps to a detail never previously attempted. Research to enable this included extensive on-site analysis of their river catchment topographies and desk-top studies of numerous old maps and literary references. Walking on Water ends on an optimistic note. Drawing on his professional experience, the author proposes a practical, affordable and exciting approach to recreating riverside parks and walks in the London boroughs through which the hidden rivers passed, which uses their source waters to refresh the lakes of the Royal Parks.”

Myers breaks down the history of hidden rivers, discusses a good amount on geology and the form of the rivers, and discusses their ‘uses and abuses’, all info covered in other places, but again with a unique focus here.  The second half of the book includes specific rivers, an overall map shows some of the North Bank Rivers (click to enlarge) covered, including all the usual suspects from other books.

Also of interest is a comparative profile, showing the central London Rivers.  The relationship of the rivers in terms of altitude from headwaters to outfall is a complement to plan relationships, and particularly in the context of London where all the rivers flow into the same source, the Thames, it allow for some good comparison.

The development of the City of London is of great interest, named the chapter ‘A City Grows, Its Rivers Beggared’ and how this rapid urbanization impacted the rivers both in demand for fresh water and degradation due to pollution.  The diagram below (which would have aided with some color and texture) shows the expansion of the city, notably the sprawling growth between 1800 and 1900 (marked by the gray inner zone and outer black line).

And while the chapter on ‘Mapping London’s Hidden Rivers’ is helpful in outlining the methodology, the results that come from this work are less than stellar.  All the diagrams and maps here are black and white, using a base map derived from the Geographers A-Z Map Co (similar to Barton & Myers) which again offers legibility and usability issues that leave a lot to be desired.  While the maps in the 2016 book were in color, they seemed overly detailed and took away from the routes of the rivers. In this case, black and white flattens it all out and their small size makes the cramped and difficult to use.  A good hybrid would be a black and white base with the paths drawn in color, perhaps?

As Myers makes a point multiple times, “it was a considerable surprise to learn that there were no large-scale maps, readily accessible to the general public, which showed their routes through the metropolis.” (14)  Perhaps Barton’s original 1962 book insert doesn’t totally qualify as ‘accessible’, but it does, and much more successfully, provide a large scale map of the routes that Myers was missing. He does mention obviously using Barton, and also references a book I had not heard about previously, London Under London by a very appropriately named duo for the task, Trench & Hillman.  Another reference was to a future volume, “Walking on Water – the Hidden Water Walks” to follow this one, but I’ve not found any mention that that project came to fruition.  So perhaps that was going to be the vehicle for better, user friendly maps, that never materialized.

For each river chapter, he does include the sections of the routes, again in very small size, which I think are very helpful for visualizing the routes of streams.

The final chapter does offer a strategy for a project entitled the Hamstead Water Conduit, where he speculates on a proposal that could “recreate short, clean stretches of the Central London rivers – more particularly the Fleet, the Tyburn, the Westbourne, and possibly, the Walbrook, the City of London’s own river.” (200).  He goes on to mention that “the source waters for the Fleet, the Tyburn and the Westbourne rivers are the springs and surface water which drain naturally from Hampstead Health.  These are the only source water of the hidden rivers that have been protected from pollution and which remain eminently accessible today.” (201)

A diagram shows a proposed route, which connects existing daylit portions with new or reconfigured surface channels in places, fed by the springs mentioned above.  While not a continuous river, the result is a linear water course that works with the boundaries of the existing city fabric while taking advantage of opportunities to create surface waters.  A “…‘feel-good’ project” but one with environmental benefits, flood mitigation, recreation, tourism, and infrastructure reduction. As noted by Myers, the social benefits as well, allowing us to “lift spirits in depressing times, but also contribute a small stimulus towards better economic times.” (208)

A more technical diagram shows some of the interconnections between the old and new systems, as well as the make-up water using existing groundwater stores (a metaphorical routing) and creating a water balance that kept water uses constant while using excess flows to ‘restore’ river segments.


The strength of this book, as indicated in the above analysis, is a solid, technical background in both the formation of rivers, the geological and hydrological framework in which these waterways emerged, the development implications that drove them underground, and some realistic considerations on why it would be difficult to daylight them, as they have been so fully consumed into the existing sewer systems. But also, some defensible and plausible daylighting strategies that take these multitude of factors into play.

The glossary ‘Watery Definitions’ on page 20 is a good touch, and discussion of what is a creek, stream, river, etc. is one that few tend to delve into in any detail.  As he mentions, due to size and typology, “it might seem more approrpriate to make reference to London’s ‘Hidden Streams’ rather than to London’s hidden rivers, as the flows in them could not really be described as ‘copious’ and their water surface widths generally lay in the narrow band of between 2 and 6 metres.  However, these watercourses have been referred to historically and collectively as ‘rivers’, and so this book will perpetuate that possibly inaccurate usage.” (22)

The Disclaimer at the beginning was interesting as well, as it seemed appropriate for anyone with a background in design and engineering to include the cover-your-ass language about accuracy, liability and not using the information for specific purposes.  This shows up also in the later Barton & Myers version of Lost Rivers, but does bring up a point about representation and what it could mean.  The accuracy of old maps .  He also warns about sewer exploration, I guess as well a necessary caveat for disseminating this type of information.

Each book I’ve covered offers something unique to the conversation, and this provides a great resource for those interested in London, but also a wider context of the emergence of urban creeks and rivers which seem applicable to all places.  A level of technical rigor also makes this a valuable companion to other resources that focus on places, history, landmarks and culture.



My previous postscript ran somewhat longer than anticipated, due to the massive amount of work happening in and around New York City.  Thus a focus on this post on the cartographic, including some of the great resources available, and the rich history of maps new and old that emerge to tell a visual story of hidden hydrology in the city and larger region.  There are so many, that one who wants to dive in can jump down to the resources section below to see lots of great sites showcasing the maps, my focus here is to highlight a few I thought were interesting and beyond general map nerdiness, some that had a particular relevance to hidden hydrology.

An old version dates back to the early settlement times, from 1639 the Manatvs gelegen op de Noot [sic] Riuier (via Library of Congress) is a fun introduction to the area, north to the right showing the section of Manhattan (Manatvs) and areas surrounding.  Fun to see a map from this far back, and it does represent some of the topography and hydrology in some rudimentary ways.

The 1660 Castello Plan (original and a later reproduction drawn in the early 1900s) offers a glimpse of the tip of Manhattan, or New Amsterdam.

Many maps come via The Iconography of Manhattan Island, via Wikipedia “a six volume study of the history of New York City by Isaac Newton Phelps Stokes, published between 1915 and 1928 by R. H. Dodd in New York. The work comprehensively records and documents key events of the city’s chronology from the 16th to the early 20th centuries. Among other things, it shows the evolution of the Manhattan skyline up to the time of publication”  More: “Stokes’s worldwide research teams scoured public and private collections of maps, guides and obscure source material to complete his encyclopedic monument to New York City. It describes in detail the growth of a fortified Dutch settlement into a major city, and ultimately included six volumes sold to subscribers and libraries in a limited edition of 360 sets printed on Holland-made paper and 42 on Japanese vellum.”

The following plate from this Iconography is from 1693, showing Manhattan and the shift from New Amsterdam to Nouvelle Yorc:

The Bradford Map is another resource, showing “…the city of New York at the time of the granting of the Montgomery charter …” and “from an actual survey” and starting to highlight some hydrological resources like the Collect Pond.  The map is a reproduction from the 1800s, but shows the area in 1730 and is similar to the later Maerschalck map, showing similar area in the 1750s.

A beautiful map is a 1777 version Plan de New-York et des Environs, showing a similar zone with a lot more detail, a precursor of some of the more detailed maps (and sophistication of mapmaking) in the late 18th century.

A larger area comes via 1766-1777 and the Plan of the city of New York in North America – surveyed in the years 1766 & 1767 by Ratzer, showing a larger zone beyond the Hudson and East Rivers.

From the header above we see the influential British Headquarters map that was used heavily in the creation of the Welikia project.  This map shows the larger area of Manhattan in fine detail, with topographic relief – a zoomed in section shows why this was such an important historical document.

Fast forwarding a bit to the early 1820s, the Randel Map was an atlas of.  Via The Greatest Grid website: “Between 1818 and 1820, John Randel, Jr. prepared an atlas of 92 watercolor maps that vividly illustrates the properties, old roads, and major features of pre-grid Manhattan as well as the future location of the new streets and avenues of the 1811 grid.  Drawn at a scale of 100 feet to 1 inch, the Randel Farm Maps provide a detailed picture of Manhattan before its transformation. Hand drawn and colored, they are among the most significant documents in the history of New York as well as a rarity in American urban history, as no comparable maps exist for other early-19th-century American cities”.   There are 92 individual maps, but an online map stitches them together in a beautifully detailed composite here.

The maps got more broad, with titles to fit like “Topographical map of the city and county of New-York, and the adjacent country : with views in the border of the principal buildings, and interesting scenery of the island.” from 1836 showing the entire island of Manhattan with relief,

This was perhaps the precursor to one of the most fantastic maps, that created by Egbert L. Viele, the 1865 gem “Sanitary & Topographical Map of the City and Island of New York.

The detail is amazing, and it’s available as a high-res download at multiple sources, including Wikipedia which describes it as such: “…survey of the original streams, marshes and coastline of New York City, superimposed over the street grid. The map is still used by modern geotechnical engineers, structural engineers and planners to design the foundations of new buildings and structures in the city.”  A few close ups illustrate this point, and allow for georeferencing to the modern city:

A few other maps that caught my eye, specific to Hidden Hydrology Broadside of the Collect Pond, New York and Steam Boat (Five Points) highlights that the pond was still there in 1846 (or at least as represented here from 1793).

And the birdseye perspectives are another great resource, showing a different viewpoint.  As a tool to communicate place, I’ve always been fascinated by these, such as this 1870 version from Currier & Ives (source unknown as I got this via Twitter) but I believe it’s from Library of Congress.

And some map-objects and infrastructure systems that are fascinating, including this one, a ” Sketch showing the ground under carriageway at intersection of Wall, Broad, and Nassau Streets : as occupied by water, gas, steam, pneumatic, cable and electric pipes, sewers, basins, culverts and vaults to houses, etc., February 1885″  


There’s also a wealth of maps covering many Boroughs, but these map be for another time – and the resources below offer lots of chances for locals or the curious to dive in to more depth.


There’s great interactive maps like  the interactive to quirky side, there’s a fun historical Spyglass Map, showing the New York City of 1836 vs. today,   The Smithsonian, had David Rumsey provide some discussion of this map to go along with an article about it, where: “Rumsey looks to the map’s delicate shading to tell much of its story, noting that the heavily shaded areas represent the most densely populated portions of the city at the time of the ma’s drawing. “Pretty much everything past 14th St. is country,” he explains, adding that much of what is considered Manhattan today wasn’t yet settled. In addition to the population shading, the hills of Manhattan are shown by hachures, an antiquated method of showing relief on drawn maps. “A lot of the history of Manhattan is the destruction of its hills,” Rumsey says. “Basically that topography was obliterated, except for Central Park.”

And a fun but perhaps limited in usefulness ‘Urban Scratchoff’, which does a similar thing with by revealing a 1924 map underlay.  I feel as if I keep scratching but never really win anything.


A great site focused on Manhattan that filled in much of the above content is the map page of Manhattan Past which is connected to the site and book ‘Street Names Past & Present’ focused on the place name origins of area around the City.  The maps are broken down chronologically back into the 1600s, with links to originals and some brief text, a great primer for delving into the larger pool.

Additionally, The Greatest Grid is a site that emerged from the exhibition The Greatest Grid: The Master Plan of Manhattan 1811-2011, at Museum of the City of New York in 2011 to 2012, which “documents the creation of Manhattan’s signature grid, which set a remarkably flexible framework for growth as a town of 100,000 in 1811 became today’s world city of 1.8 million people (in Manhattan only). Balancing order and freedom, uniformity and individuality, the grid continues to serve as a model of urban planning in the 21st century.”  Some great background on the development of the city and the grid, as well as great maps, are found within.

The resources available are amazing, drawing on local and international institutions – one of the best being the Open Access maps from the New York Public Library, where the The Lionel Pincus & Princess Firyal Map Division has over 20,000 free, high resolution downloads available, many of the maps above coming from this source, and their active Twitter feed @NYPLMaps showcases many more.

Plan of the town of Brooklyn and part of Long Island – 1767 (NYPL)

Another I thought was very comprehensive and well organized was via Stony Brook University called NYS Map Pathfinder.  Larger institutions carry plenty of maps of New York City due to it’s significant, as The Library of Congress has extensive holdings for New York City, and as most map nerds know, the David Rumsey collection is the go to for maps, including lots for New York, with some great tools, as well for viewing and sorting.  Just sifting through you find the historic, but a wealth of interesting map techniques, such as this Map of Greenwich Village made for the Whitney Studio Club from 1920.

And speaking of other non-historic maps, not specific to hidden hydrology, I’d be remiss without mentioning the New York version of Rebecca Solnit’s atlas collection Nonstop Metropolis, A New York City Atlas, authored with Joshua Jelly-Schapiro and true to form with the other regional versions from San Francisco and New Orleansis part of the compendium of maps as storytelling devices.  Read this great long essay via Public Books entitled Visible Cities by Laura Yoder for where she dives into “maps that catalogue social and cultural complexity, and teach us to engage with difference in productive and generous ways.”  Another good review via Hyperallergic, “Creating an Atlas of Overlooked Cartography for New York City” where they relate that “Every map is an intense act of creative collaboration, with essays and illustrations in Nonstop Metropolis from over 30 artists and writers.”  The image below is indicative of this style, showcasing “Wildlife”

A book that looks interesting by Marguerite Holloway is the author of The Measure of Manhattan: The Tumultuous Career and Surprising Legacy of John Randel, Jr., Cartographer, Surveyor, Inventor, and another on the maps, there’s the 2014 publication Manhattan in Maps 1527-2014 by Paul E. Cohen &‎ Robert T. Augustyn 

For modern mapmakers, there’s a rich collection of resources, including NYCityMap and OASIS both displaying tons of thematic info on current conditions in the city, the latter even providing a historical slider showing the Mannahatta layering.

I could post maps and larger stories of hidden hydrology every day for a year and not run out of interesting tidbits here in the Big Apple, which reflects the richness of historical context and also the passion for many people to investigate their hidden hydrological histories.  And it seems a fitting segue to where we are heading.  Next up, we head over the pond to the undisputed champion of Lost Rivers – London.

Stay tuned.


HEADER:  Facsimile of the unpublished 1782 British head quarters coloured manuscript map of New York & environs – via David Rumsey

As I mentioned, New York City and the larger metropolitan region is an important case study in hidden hydrology, with a range of interesting activities spanning urban ecology, history, open space, art, subterranean exploration, and much more.  As a city with a long and vibrant history it’s not surprising that the story of water would be equally compelling.  The following few posts will expand on some of the key activities that shape the hidden hydrology of the city.

Times Square then and now: the area featured a red-maple swamp frequented by beavers, wood ducks, and elk. – via the New Yorker

Almost a decade or so ago, I read this story in the New Yorker about Henry Hudson, the year 1609, a map, and an effort by a group of people, including ecologist Eric Sanderson, to research and visualize the historical ecology of New York City. I posted this  and posted it to my blog Landscape+Urbanism.  This was one of the catalysts, and I’ve discussed this project in the past as one the key Origin Stories around my personal interest in Hidden Hydrology.

Mannahatta Map – via NYC 99 ORG

The publication of the ideas with the publication of the Mannahatta book (originally out in 2009 and with new printing in 2013) and this broader work by Eric Sanderson (and his very well loved TED Talk) and crew on visualizing and creating rich data landscapes for Manhattan and the larger region is constantly compelling, and the shift to a broader scope under the name The Welikia Project in 2010 was really exciting to see.

The Welikia Project expands the  provides a rich and well documented study of the historical and ecological study of New York City dating back over 400 years and inclusive of a range of interpretation from art, ecology, and design.  The overview of Welikia here provides a much longer and more complete synopsis of the project, but I’ll pick some of the interesting ideas I think are worth of discussion in information larger ideas about hidden hydrology.

The main page offers a range of options that the project provides.  Per the overview page, “The Welikia Project (2010 – 2013) goes beyond Mannahatta to encompass the entire city, discover its original ecology and compare it what we have today…  The Welikia Project embraces the Bronx, Queens, Brooklyn, Staten Island and the waters in-between, while still serving up all we have learned about Mannahatta.  Welikia provides the basis for all the people of New York to appreciate, conserve and re-invigorate the natural heritage of their city not matter which borough they live in.”

Tools include some downloads include curriculum for teachers to use, and some publications and data also available which would be fun to explore more.  A few notable bits of info worth exploration is this page “How to Build a Forgotten Landscape from the Ground Up”, which is a nice overview of the methodology used by the Welikia team, and provides a nice blueprint for organization of data that is transferable to any locale.

The original historical 1782 British Headquarters map was the genesis of any number of overlays that, once digitized into GIS, provided a historic base to layer additional information from other sources, along with inferences by professional ecologists and other members of the team.  These were also able to be georeferenced, which allows for the overlay of historic to modern geography, which becomes the basis for some of the larger interactive mapping we’ll see a bit later.  A map series from the Welikia site demonstrates the layering and aggregation possible.

1782 British Headquarters Map
Elevation differences from 1609 to today
Digital Elevation Model
Ecological communities

The concept of Muir Webs was also a fascinating part of the original Mannahatta book, so you can learn more about this on the page and via this presentation “On Muir Webs and Mannahatta: Ecological Networks in the Service of New York City’s Historical Ecology”

This Muir Web shows all the habitat relationships for all the species on Mannahatta. Visualization by Chris Harrison of Carnegie-Mellon University. ©WCS

Welikia Map Explorer – Lots of interesting background that I’ve literally barely scratched the surface of.  As I mentioned, the beauty of Mannahatta was the visualization of the historic surface, and through mapping with georeferenced location, provided an easy opportunity to create overlay maps of historic and modern.  The key part of this project is the Welikia Map Explorer, which offers a simple interface that can unlock tons of information.  Starting out, you have a full panned out view of the 1609 map visualization for Manhattan.

By selecting an address or zooming, you can isolate locations or just navigate.  It’s got that same video game quality I mentioned in my recent post about the DC Water Atlas, with some exploratory zooming and flying around the landscape looking at the creeks, wetlands and other area, you half expect to click and launch some next part of a non-linear exploration game.   The detail is amazing, and the juxtaposition between the very urban metropolis of New York City with this lush, pre-development landscape is striking both in plan, as well as some of the 3D renderings above.

You can then select any block and it will pop up a box that allows you to access lots of data underneath on a smaller level.

The interface provides layers of site specific data, and breaks down items like Wildlife, potential presence of Lenape (original native inhabitants, and Landscape Metrics. “Welcome to a wild place: this block in 1609! Through the tabs below, discover the wildlife, Native American use, and landscape factors of this block’s original ecology, as reconstructed by the Mannahatta Project. You can also explore the block today and sponsor the Mannahatta Project into the future.”

The Modern Day tab relates back to OASIS maps of the modern condition, making the connection of specific places easy to discern. “Landscapes never disappear, they just change. Click on the image below to see this block today through the New York City Open Accessible Space Information System (OASIS) and learn about open space and other contemporary environmental resources.”

For the beautiful simplicity of the map, it’s easy to lose sight of the fact that this is dense with real data and models that attempt to provide a real viewpoint to what each parcel was like 400+ years in the past.  We discuss baseline conditions much in design, stormwater, ecology and habitat studies, and this level of evidence-based, site scale data is so important to decisonmaking not just in terms of former waterways, but in restoration and management of spaces.  This is summed up on the site:

“An important part of the Mannahatta Project is not leaving ecology in the past, but to appreciate it in our current times, to see how we can live in ways that are compatible with wildlife and wild places and that will sustain people and planet Earth for the next 400 years.”

Visonmaker.NYC – Of the more recent expansions of this is the creation of Visionmaker NYC, which “allows the public to develop and share climate-resilient and sustainable designs for Manhattan based on rapid model estimates of the water cycle, carbon cycle, biodiversity and population. Users can vary the ecosystems, lifestyles, and climate of the city in an effort to find and publish sustainable and resilient visions of the city of the future.”

Worthy of a full post on it’s own, the idea is to emphasize the link between the Mannahatta era of 1609, the current era four centuries later, around 2009, and a future world into the future another 400 years in 2049.  This gives a great opportunity to create a key linkages between historical work, current scenarios, and future conditions.

As they mention: “A vision is a representation of a part of New York City as you envison it. You select an area and can change the ecosystems – buildings, streets, and natural environments – as well as the climate and the lifestyle choices that people living in that area make.” and you can also view other published visions done by users of all ages.  The interface is similar to Welikia, as it allows an overlay of layers with varying transparency for comparison.

More on this as I dive in a bit, but you can also watch a more recent 2013 TEDxLongIslandCity video shows this tool in more detail:

The mapmaking is of course pretty awesome, and they keep posting new visualizations and updates, such as this 1609 topo map, posted via Twitter via @welikiaproject on the “Preurban (year 1609) topography and elevation of

There was also some great local quirky info, such as this map and historic photo showing perhaps the strangest remnant geological remnant in a city I’ve seen.  Via Twitter from December 2016, “29 Dec 2016  “Rocky outcrops in NYC, were mostly concentrated in Manhattan and the Bronx and composed of schist and gneiss.”

You can and should also follow Sanderson via @ewsanderson , continuing his work at the Wildlife Conservation Society and to see him giving talks and tours around the City.  A recent one mentioned that “After seven years of effort, he will share for the first time the digital elevation model of the pre-development topography his team has built, discuss why the climate and geology of the city together make our landscape conducive to streams and springs, give a borough by borough tour of ancient watersheds, and suggest how we can bring living water back to the stony city again.” 

Sounds great, and I wish sometimes to be a bit closer to be able to experience this around these parts.  Continuing to inspire beyond Mannahatta to the broader Welikia Project, Sanderson and all the crew that make it a reality is a great example anywhere in the world of what’s possible in tracing the threads between history and contemporary environmental issues.  If someone today gave me a chunk of money and said do this for Portland or Seattle or both (and honestly folks, we really should) I’d jump on it in a second.

The history of hidden hydrology isn’t just that of erasure, but of ‘made land’, significant areas that were added to cities through the process of landfilling. A June, 2017 post from National Geographic’s All Over the Map blog captures this on the east coast, telling the story of “How Boston Made Itself Bigger” illustrated with some fantastic maps.  The focal map shows the extent of landfilling throughout the span from 1630 to present, from the original shape of the downtown area (Shawmut Pennisula), and the modern shoreline in blue.  The massive extent of fill is pretty evident with significant percentage of the metro area on land that at one point in the not-so-distant past was water.

Much of Boston’s coastline is man-made land. The original shoreline, from 1630, is visible in dark green on this map. Land made between 1630 and 1995 is light green. PHOTOGRAPH COURTESY OF THE NORMAN B. LEVENTHAL MAP CENTER, BOSTON PUBLIC LIBRARY; CARTOGRAPHY BY HERB HEIDT AND ELIZA MCCLENNEN, MAPWORKS

A 1630’s map shows the Shawmut, and the narrow spit of land that connected this (for a time at least) to the mainland (rotated north to the right).


The impetus for the post on Boston was driven by lowering of the water table to levels that started to potentially reveal many of the wood piles, which stay preserved in anerobic conditions – as similar situation to a water-based city like Venice, for instance, but once water levels reveal them, makes them highly susceptible to rot.  From All Over the Map:

” A large portion of the city sits on man-made land. Structures built on the landfill are supported by dozens of 30- to 40-foot-long wood pilings, similar to telephone poles, that reach down through the landfill to a harder layer of clay. These pilings sit entirely below the water table, which protects them from microbes that would attack them in dry air, causing rot.”

The filling also was facilitated by damming, such as seen below, where what was the current Back Bay “neighborhood is marked “Receiving Basin” on this map. Boston Common is the uncolored area marked “Common.”  By damming the areas, thus separating them from the larger bodies of water and tidal changes, it was easier to then start to develop and fill in with railroads, industrial lands and more development.  The image shows expansion parcels, notably widening of the neck and further encroachment into the water.


As mentioned, it wasn’t just increased development area that was driving the land filling:  “Over the years there were many other motivations for making new land, including making harbor improvements, burying pollution from wastewater, safeguarding public health, building public parks, adding railroad tracks and depots, adding more shipping facilities to compete with other port cities, establishing appealing neighborhoods to entice Yankees to stay (and to counter Irish immigration), and creating space for the city’s airport.”  Another driver was public health, including filling in ponds and creeks, which were starting to smell.  Concurrent with filling (and a great source of fill) was removal of hillsides, another common city strategy, which provided plenty of earth to create more land while levelling, in this case, Beacon Hill. (via Wikipedia)

Cutting down Beacon Hill in 1811; a view from the north toward the Massachusetts State House

The Back Bay was a source of both significant filling due to its location as a locus of sewage (and a super complicated hydrological regime change that was involved), as mentioned in All Over the Map“…an 1849 report from a city committee that reads: “Back Bay at this hour is nothing less than a great cesspool into which is daily deposited all the filth of a large and constantly increasing population … A greenish scum, many yards wide, stretches along the shores of the Western Avenue [Mill Dam], whilst the surface of the water beyond is seen bubbling like a cauldron with the noxious gases that are exploding from the corrupting mass below.”  The area was filled with trash and other debris, as fill material was less available, along with being set on the aforementioned pilings, placing it in the awkward position of being even now “one of the city’s most desirable neighborhoods, but also among the most vulnerable to foundation rot.”

I’d be remiss as well if I didn’t mention, in the context of this, one of my favorite Olmsted projects, the Back Bay Fens, which came at the tail end of the filling, in the 1870s (via Wikipedia):  “Olmsted’s challenge was to restore the spot of marsh which was preserved into an ecologically healthy place that could also be enjoyed as a recreation area. Combining his renowned landscaping talents with state-of-the-art sanitary engineering, he turned a foul-smelling tidal creek and swamp into “scenery of a winding, brackish creek, within wooded banks; gaining interest from the meandering course of the water.”

The extent of land filling is hard to visualize, but the map that shows it most clearly in terms of downtown is a simple overlay of the original Shawmut Pennisula over the new shoreline (you can see the tip of the Back Bay Fens in the lower left hand corner).

Via Written in Stone…

And while not the most up-to-date map in terms of graphic style, a good way to illustrate the evolution of landfilling over time that is hard to capture on maps is this animation via the Boston: History of the Landfills page at Boston College.   Someone has probably updated this, so if you know of it, let me know any updated sources.

A later map in 1867 from the NOAA US Coast Survey below shows further expansions closer to the modern coast.  Although the land and coast changed less in the ensuing century and a half, the continuing legacy of the land filling continues to be costly to maintain, exacerbated especially in times of changing water levels that we are experiencing with global climate change.

The hydrology as well, although hidden, is evident in repairs for pilings and other issues of groundwater – a symptom of building and ‘making land’ on areas formally water. And as concluded in All Over the Map, “…with more than 5,000 acres of man-made land—more than any other American city (except perhaps San Francisco, where the landfill hasn’t been comprehensively totaled)—Bostonians will be living with this problem for the foreseeable future.”


Plenty of folks have covered this in Boston and the idea of land filling, with a variety of maps and imagery, such a Boston Geology, and some more context on the pilings from the Boston Groundwater Trust.  Also, this great post from the Library of Congress ‘Putting Boston on the Map: Land Reclamation and the Growth of a City’ features a few maps, including one of the earliest maps, which highlights the former tight pennisula.

William Burgis and Thomas Johnston. “To his excellency William Burnet, esqr., this plan of Boston in New England is humbly dedicated by his excellencys most obedient and humble servant Will Burgiss.” 1728. Geography & Map Division, Library of Congress.

And a fabulous birdseye from the late 1800’s showing more significant filling.

Charles R. Parsons and Lyman W. Atwater. “The city of Boston.” 1873. Geography & Map Division, Library of Congress.

See the some of the timeline of history via the USGS series of maps of Boston here, or a more interactive map via MapJunction with an array of base and historical map overlays of Boston, including a cool 4-way slider that allows you to do an overlay left-to-right and control transparency top-to-bottom.  A couple of screen shots of these.

1776 Hybrid Map (Boston and Environs – Pelham)
1917 Hybrid Map (Boston Bromley Atlas)

And an out-of-print book worth tracking down is Nancy S. Seasholes Gaining Ground: A History of Landmaking in Boston (MIT Press, 2003) where the “story of landmaking in Boston is presented geographically; each chapter traces landmaking in a different part of the city from its first permanent settlement to the present.” 

Many cities share this trait, using fill to gain area, which has been both boon and boondoggle.  Locally, a great resource worthy of a deep dive is Too High and Too Steep: Reshaping Seattle’s Topography by David B. Williams (University of Washington press, 2015), which I’ve read and re-read which explores in detail, a similar massive manipulation and use of made land here in my current particular West coast City.

HEADER:  Image via National Geographic, “A map of Boston in 1775 shows the dam that closed off Mill Pond, which was later filled in to make new land. “  PHOTOGRAPH COURTESY OF LIBRARY OF CONGRESS


Having gone to undergraduate school at North Dakota State University in Fargo in the mid-1990s, one became aware of a distinct transitional zone as you headed east towards the Twin Cities.  A short drive across the Minnesota border, you could see what was the shoreline traces that marked a clear shift of geology and with some study, begin to piece together the story of the past millenia, involving a glacier, a lake, and the reason the Red River flows to the north.

A recent Ghosts of Minnesota post “A Minnesota beach where there is no water”  by Troy Larson, reminded me of this place and the influence the immense glacial Lake Agassiz on the landscape of the upper sections of the Plains, a lake formed at the end of the last ice age, some 8,000 to 14,000 years ago.

A map of the territory by Warren Upham, from the earth 19th Century shows the extent of the Lake, and as mentioned by Larson, “Today, Lake Agassiz is believed to have been even larger than what is represented on this map.”

Larson gives some context:

“Lake Agassiz was a massive body of fresh water in the middle of North America, larger than all of the Great Lakes combined. As the ice sheet retreated, ice dams held back the meltwater to create glacial Lake Agassiz. As the lake drained, sometimes slowly, other times in sudden, catastrophic outflows, the lake shrank and changed, leaving behind a table-flat landscape with some of the richest farmland in the world, and even sandy beaches from it’s ever-shifting shoreline. To the geologically educated, the signs of Lake Agassiz are everywhere, but even to those like myself, without a geologic eye, there are places where you can see the remains of this monster lake.”

A close up shows the area around the North Dakota-Minnesota border, bisected by the Red River (of the North).

The post covers some photos of the area near Fertile, Minnesota, home of the Sandhill Recreation Area and nearby Agassiz Dunes Natural Area, and as explained in the Ghosts of Minnesota post by Larson: “These dunes were formed as the ice sheet retreated and the weather became dry and hot. In wetter times, foliage appears and covers the dunes, and in dry periods, the growth retreats and the sand becomes more visible.”  With places like a dune called “Death Valley” named due to the instability of the shifting sands, this is an atypical plains landscape.

image – Ghosts of Minnesota

image – Ghosts of Minnesota

While there are plenty of lakes in Minnesota (yes, well over 10,000) the sort of expansive lake left traces of a more significant water body, as mentioned by Larson:

“The sand feels just like beach sand. It’s a soft, fine grain sand that shifts beneath your feet when you walk on it.” 

image – Ghosts of Minnesota

A more expansive map from a recent CBC article that covered a new book by Bill Redekop (@billredekop) entitled “Lake Agassiz: The Rise and Demise of the World’s Greatest Lake” exploring the hidden mystery of the lake.  “For millennia, the evidence of its existence remained hidden in plain sight, but slowly details of the landscape began to merge in the minds of people passing through the province.” The modern map (via the CBC article) shows a more expansive Lake Agassiz, and the extent:

As Redekop explains, the investigation of the hidden connects the modern to the historical.  He summarized the feeling after writing the book:

“”Now I have two landscapes: the one that I see and the one that I imagine, that I know was there 10,000 years ago.”

The deep time of geology, as mentioned here in the post on Seattle area, leaves many traces and clues to .  Beaches without lakes, valleys without creeks, all connect us to a historical past that shapes our present and future.

Header image of Lake Agassiz dunes – via Ghosts of Minnesota

I posted some amazing images last year of changing course of the Willamette River captured with LIDAR, evoking wisps of smoke leaving a palimpsest of tracings across the landscape.  A recent article from National Geographic’s site ‘All Over the Map‘ entitled ‘See the Strange, Beautiful Landscapes Revealed by Lasers‘ reminded me of the beauty of this digital technique, showcasing some additional regional imagery and including hydrology and geology, this time focused in the State of Washington.  A few of the images included:

The Quinault River on Washington’s Olympic Peninsula has meandered extensively in the past, leaving behind dry, abandoned stream channels filled with river sediment that are revealed by LIDAR.
Channels in northwestern Washington formed when melting glaciers caused major floods. The channels are highlighted near the center of this LIDAR image.

The images are beautiful and intriguing, owing to the ability of LIDAR to penetrate vegetation layers to reach surface levels often unseen with traditional methods.  The beautiful imagery in the article is from the Washington Geological Survey site ‘The Bare Earth’ which is a descriptive resource on “How lidar in Washington State exposes geology and natural hazards”.

While useful for many types of analysis, this is particularly important to identification of landscape hazards, which had devastating impacts in 2014 in Oso, a town north of Seattle, and you can see some of the images highlighting landslide activity in the region.

A landslide covered with vegetation near Deming, Washington is revealed with LIDAR.
Old landslide scars on the Cedar River near Seattle are normally obscured by forest, but are plainly visible in this LIDAR image.

The most intriguing image to me was the Mima Mound Natural Area Preserve, which I hadn’t known about before reading this, which look much like a magnification of dermis instead of earth.

The mysterious Mima Mounds near Olympia, Washington are beautifully exposed in this LIDAR image. The origin of these mounds, which are 6 feet tall and 30 feet wide on average, is unclear and has been attributed to gophers, insects, wind, earthquakes, and the shrinking and swelling of clays.

The landscape itself is subtly rolling like an earthworks art project, and the reasons for their form is up for debate, as seen in the caption above.  The landscape itself is subtle and beautiful, definitely motivated to take a trip down to Olympia.

The pages on the great context on how LIDAR works with a story map of some visuals along with descriptive illustrations.  Per the WGS site,

“Lidar (light detection and ranging) is a technology that uses light pulses to collect three-dimensional information. Lidar data is often collected from an airplane using a laser system pointed at the ground. The system measures the amount of time it takes for the laser light pulses to reach the ground and return. Billions of these rapidly-collected measurements (points) can create extremely detailed three-dimensional models of the Earth’s surface. See the diagram below to better understand how airborne lidar is collected.”

A breakdown of the different maps that be extracted from the process.

The beauty of LIDAR is the ability to give an alternative view that is impossible to capture in other ways, particularly in deeply vegetated sites, with lots of coniferous vegetation. Again, from The Bare Earth site: “In geology, lidar bare-earth models allow closer study of geomorphology, which is the study of the origin of the topography of the earth. Landslides, faults, floods, glaciers, and erosion leave their mark on the landscape, and while these marks can be hidden by dense vegetation, they can’t hide from lidar.”

Harkening back to the previous posts of the geology of Seattle, the glacial retreat was a major factor in the Seattle-area geology and current hydrology.  The image below shows an aerial image, which reveals little of this feature, but the Lidar image shows the directional scarring and drumlin deposition around Hood Canal in sharp relief.

LIDAR shows the landscape around Hood Canal, a fjord in the Puget Sound, which is filled with elongated, rounded hills known as drumlins that were left behind by glaciers.

A video as well elaborates on the technique:

Check out more of Betsy Mason and Greg Miller at All Over the Map and follow them on Twitter @mapdragons

Header image, like many of the other images in the post, is from Washington Geological Survey, via National Geographic,.  The header shows “The floodplain and dry, former channels of the Chehalis River in western Washington State are revealed by this LIDAR-based elevation map.”

While the focus of investigations in Hidden Hydrology are often around the lost, buried and disappeared, the true nature of the hidden comes up in some interesting ways.  A recent article via the CBC discusses a new find “‘This is a major discovery’: Explorers find massive ice-age cavern beneath Montreal” and discusses a hidden “Cathedral-like chamber, formed more than 15,000 years ago, [which also] features underground lake”.

The spot was found by cavers who busted through a wall in the popular the Saint-Leonard Cavern,  The cavers, “Le Blanc and Caron said they were able to pinpoint the location of the passageway using a dowsing rod, similar to the wooden divination tools sometimes used to find groundwater.  The two men, who first got into caving as a hobby, said they’ve been searching for an unknown branch of the Saint-Léonard cavern for years.”

A video of the exploration:

While groundwater and aquifers are well known to exist in cities, the relationship of surface and subsurface geology and hydrology makes for some interesting interactions with hidden hydrological regimes – in this case subterranean interface with the aquifer. Perhaps few examples as extreme as this in modern cities, but interesting to see something hidden for years emerging after so long.

Source of the header image:  Massive Underground Cavern Formed During Ice Age Discovered By Amateur Explorers (IBT)

River Piracy sounds like an exotic form of stream based pillage and plunder, but rather refers to the reorientation of stream flow from one channel to another.  Also known as stream capture, the causes vary, and include tectonics shifts which changes slope, natural dams (landslide or ice), headward and lateral erosion, karst topography, and glacial retreat.   Notable ice dams have diverted rivers, of note is the River Thames, which was shifted 450,000 years ago cause it to

A recent set of stories about the Slims River in the Yukon territory illustrates the last of these points, where the retreat of the Kaskawulsh glacier and it’s shift from the Slims River to the northwest and into the adjacent Kaskawulsh River to the southeast.  The phenomenon isn’t uncommon, but the pace in which this ‘theft’ occurred is notable: “Such a transformation has occurred numerous times throughout the planet’s geological history – often due to gradual erosion or the movement of a fault – but has never been observed to occur as suddenly, happening over just a few days in May 2016. ‘Geologists have seen [evidence of] river piracy before, but nobody to our knowledge has documented it actually happening [within] our lifetimes,’ explains Shugar, Assistant Professor of Geoscience at the University of Washington, Tacoma.” The image below shows the “aerial view of the ice canyon that now carries meltwater from the Kaskawulsh Glacier, seen here on the right, away from the Slims River and toward the Kaskawulsh River.”  

A map of the area shows the relationship of the river and the shift, which short-circuited a longer path through the Kluane River into the Yukon River and eventually the Bering Sea, now connecting to the Alksek River and flowing into the Pacific Ocean.  From a global perspective the flow doesn’t mean much, but on a local scale the impact is more acute.

From the article in the Globe and Mail, “Climate change stole a Yukon river almost overnight, scientists say. Here’s how“, which mentions the process at work:

“That water now flows into the Kaskawulsh River, a tributary of the Alsek, which runs southward to the Pacific. Following this route, it reaches the ocean some 1,330 kilometres away from where it would otherwise have ended up. Signs of the rerouting have been observed on both sides of the mountainous divide. Gauges on the Alsek River reveal that it experienced a record discharge last year. Because the river mostly flows through parks and protected lands, the increase has had no immediate human impact. On the Slims side, the effect of water loss is more obvious. Last summer, Kluane Lake dropped a full metre below its lowest recorded level for that time of year. The reduced inflow from the Slims spells a huge change for the 65-kilometre-long lake, with implications for nearby communities and visitors who access its waters for fishing and other activities.”

The quality of the Lake ecosystem is one issue also, as mentioned in the Guardian article “The river stolen by climate change”, quoting scientist Jim Best:  “The dramatic switch was caused by the rapid retreat of the Kaskawulsh glacier – thanks to climate change – which caused the flow of the meltwater to be redirected, and prompts questions about the impact it could have on the surrounding Yukon territory. Best points out that while much of the southern part of the territory is ‘sparsely populated’, and therefore potential flooding caused by the extra water is unlikely to cause any ‘real human impacts’, the opposite issue could be a cause for concern further north.  ‘If Kluane Lake levels go down,’ he predicts, ‘the lake could thus have no inflow and no exit flow, which would radically alter lake water nutrients and circulation, and this may impact on the lacustrine ecology. In addition, if the lake outlet were to dry up as a consequence, this river would be dry or far lower and thus the few habitations along it would be affected.’”

The dry valley left over, in this case the Slims River, is referred to as a wind gap, and scientists have discussed the potential issues erosion and dust storms.  As noted in the CBC story, “Retreating Yukon glacier makes river disappear“, the river is: “…prone to dust storms.  “It’s certainly not unusual to see rapid drainage changes in and around these glaciers. It’s a common situation,” Bond said.  “Until vegetation really starts to stabilize that floodplain, it’s going to be a dusty place, I’d imagine … It will be a really interesting study to see how that floodplain evolves in the next ten years or so.”


Week three of the Waterlines class featured Seattle writer and geologist David B. Williams.  Perhaps best known as the author of the recent ‘Too High and Too Steep’, a chronicle the large-scale manipulations (topographic and hydrologic, to name a few), Williams shared a more focused talk on his upcoming book Waterway: The Story of Seattle’s Locks and Ship Canal, which coincides with the Centennial of the Hiram M. Chittenden Locks this year.  Following the course theme, and touching on some previous topics, the story encompasses the trials and tribulations to get the locks built, and the large-scale impacts that such endeavors have on the ecological and hydrological systems of Seattle.

David is an engaging storyteller, so he laid out the evolution of this significant part of Seattle’s history, touching on the geology (with the north south orientation how important the waterways were to getting around, especially, east-west movement), and the use for years by native people, who used the portage between Lake Washington to Lake Union, and then a quick connection to gain access to the ocean, and vice-versa, for the past 10,000 to 12,000 years, with stories of Kitsap Suquamish coming to Lake Washington because it was one of the largest freshwater lakes in the region.  The idea of a ship canal of some sort is as old as Seattle itself, first pitched by Thomas Mercer in 1854 and finally coming to fruition as a way to move coal, timber, and people, after many attempts 63 years later.  In fact there were multiple routes proposed and attempted with big Seattle names like the aforementioned Mercer, along with Burke, Denny, and Gilman, cutting through Smith Cove, routes across what is currently downtown, and one of the most absurd in Seattle’s history – the Semple Canal.  This map shows a number of these routes, and also the one natural, yet not very viable connection vai the Black River, which was mentioned in the previous post on Seattle archaeology as outlet from Lake Washington and would eventually fall victim to the draining of Lake Washington.

By Dennis Bratland – Own work, CC BY-SA 4.0,

As mentioned, Semple’s Canal was perhaps the craziest scheme, wanting to slice through one of Seattle’s seven hills, Beacon Hill, which stands almost 350 feet tall.  Williams documents it on his blog in this post, with a couple of graphics showing the route and section cut (noting a maximum cut of a mere 284′-6″), highlighting the absurd notion of cutting a canal through a hill, although a good portion of the material removed from the canal before it was shut down was used to fill the Duwamish estuary into what is now industrial lands, and frankly, based on some of the other history, it would not have surprised me if this would have happened.

The eventual route of the Canal was landed on eventually towards the end of the 19th century, connecting to the Puget Sound through the existing Shilshole Bay and the eventual location of the locks, connecting through Salmon Bay, which was a fluctuating saltwater tide zone, connecting through the Fremont Cut to Lake Union, and the Montlake Cut connecting Portage Bay on the west with Union Bay and larger Lake Washington on the east.

The conditions prior to implementation show Salmon Bay connected to salt water, and involved slicing through Ross Creek and wetland zones between Salmon Bay and Lake Union, where a creek was feeding the Bay.  To the east the portage had become a narrow log flume at the narrowest point connecting Union Bay and Portage bay, completing the connection from lake to sea.

As mentioned, the eastern Montlake Cut was used as a log flume with a narrow channel (developed by Denny and others) connecting through Portage Bay, and a similar effort was made to connect through Ross Creek via what is now the the Fremont Cut.  A photo showing the area looking from Union Bay towards the west from Paul Dorpat’s blog showing the isthmus with Portage Bay in the distance prior to ship canal.  This area was sliced through with a log flume (seen on the 1894 map above) in the 1880s and at times through the early 1900s to move timber from inner areas to Seattle and beyond, setting the stage for the eventual connection.

A second image showing the narrow connection of the log sluice from 1886 that is seen on the 1894 map, one of the thin connections which eventually were expanded for free flow of goods and people across Seattle.  A dam at the upper end held Lake Washington above the level of Lake Union, and logs were dropped into this chute to float on the next leg of the journey.

While the connections seem logical, the elevations of each water body were different, with the level of Lake Union around +20, the level of Lake Washington at +29, and Salmon Bay elevation lower as it entered the Puget Sound, often not having standing water at times.  The process of building the locks set all of these elevations at the same as Lake Union, which raised Salmon Bay and made it a continuous fresh water bay, which is why it works as a place to over-winter fishing fleets as it is today (see Deadliest Catch) to keep boats out of salt water.  It also lowered Lake Washington, which as mentioned disconnected the lake from it’s natural outfall at the Black River to the south, replumbing the south area of Seattle while creating a whole lot of new lakefront land.  The completion of construction of the locks and the eventually breaching of the Montlake coffer dam (below) and the other coffer dams at the Fremont Cut, (after having to shore them up a few times), filled Salmon Bay with fresh water, and caused Lake Washington to drain down the 9 feet slowly over a few months

The locks, which opened to fanfare and massive 4th of July celebration in 1917, are fun to visit today to watch ships come in, go to the fish ladder, and see the activities.  According to Williams, these are the only government locks in the US that are crossable to the public (didn’t know that) and the main traffic, although peppered with an occasional working vessel to Portage bay, consists mostly of pleasure craft.  Also, while they did originally build a fish ladder, it didn’t work well (and was improved years later, which make a fun viewing opportunity).  Williams mentioned that fish tended to just get into the locks and ride up to travel upstream.  It’s an interesting resilience story that fish that were cut off from the Cedar River where they spawned when the Black River was disconnected, and instead of heading up the Duwamish/Black/Cedar to the south, would still be able to figure out how to get upstream via alternative routes via Shilshole miles north from their original spawning route. Talk about a well established navigation system.

The impacts for Seattle, much like the other massive changes, ended up having huge economic implications in positive ways, with the ability to tap into industrial lands for coal, timber, and shipbuilding, and some minor military use, along with what are mostly now marinas for pleasure craft today.  The fact that maritime industries are only second to aerospace in the Seattle economy is surprising, which owes much to the ship canal.  Seems a common story for Seattle, make massive change and reap the benefits (to some), even if it cuts off a river that happens to be the home place for local Native people.  To comprehend the 60+ year journey from idea to fruition, and the hundred years of operation since, another story of changing land and waters influencing our urban lives every day. Excited to see some of the events and read David’s upcoming book for more.  On that note…

Addenda: Making the Cut

A great resource on the upcoming centennial festivities is the website Making the Cut: The Locks, The Lakes and a Century of Change, which provides info on events, much of the history mentioned above, and a good section on historic maps which shows a good cross section of hidden hydrology in relationship to the hydrological manipulations to connect the lakes to the ocean.  A series of before and after maps documents the changes in the locks, Lake Union and Lake Washington, and other areas.  The series below highlights the evolution from the tidal marsh of Salmon Bay prior to the locks being installed in 1916 to the freshwater waterway today.

Salmon Bay – Today
Salmon Bay – prior to 1916 | Blue = Water |  Green = freshwater wetlands | Pink: saltwater wetlands | Brown: intertidal areas (or tidal flats)