Category: watersheds

Frog Taxis & Wildlife Ways

Jason Kingcase study, ecology, habitat, lakes, landscape, oregon, places, portland, rivers, watersheds, wetlandsLeave a Comment on Frog Taxis & Wildlife Ways

In Northwest Portland, Oregon, red-legged frogs living in Forest Park face a dangerous commute in the fall and winter, traversing from their upland homes down to the spawning grounds adjacent to the Willamette River. The species typically is found in conifer hardwood forests that have an aquatic-terrestrial connection to ponds and wetlands as part of their life cycles.

Northern Red-legged Frog

The degree of landscape changes inherent over time is seen in a series of maps spanning the previous century and a half of urbanization, centered near present-day Harborton, the location of a critical habitat connection for the frogs. From the original surveys in the 1850s, the area was lightly developed, and the areas noted as “Timber, Fir, Cedar, Maple, Hemlock, Yew, etc.” showing the zones that would become modern Forest Park and the uninterrupted upland to lowland connections along the Willamette River.

1855 General Land Office Survey Map (via BLM)

By the 1900s and the mapping from the USGS Topographic Survey, some development was happening along the water in the early town of Linnton, and the rail lines were built that started to sever these historical ecological connections.

1897 USGS Topographic Survey (via TopoView)

The current aerial image shows the clear line marking upland to lowland as separated by roadways and more impervious industrial development located along the Willamette River, reducing the amount of shoreline habitat.

2024 Aerial Image (via Google Earth)

The historical upland to lowland conditions has been radically disturbed along the entire margin of Forest Park. We could infer from the series of maps that historically, the frogs had significantly more habitat options along a much larger zone (and even more if you look at maps south of here showing additional lakes and wetlands), and that over time, a series of human-made linear barriers (railroad, roads) and urbanization cut off connections while reducing overall shoreline habitat. This ultimately resulted in a severe decline in several species populations, including the red-legged frogs.

As you see from a zoomed-in area, the major impediment for the frogs is a gauntlet, including a four-lane Highway 30, another smaller side road, and railroad tracks that prevent frogs from safely accessing the breeding area around the Willamette. Described by many as a real-life game of Frogger, the result is documented mass killings of frogs that attempt migration to these zones in rainy seasons.

Frogger (via Atari Age)

As a response to the negative impacts of the species, an intrepid group of volunteers has implemented what they call the Frog Taxi. Starting in 2013, as documented on the site Linnton Frogs, the group has mobilized annually to collect frogs from Forest Park, transporting them across Highway 30 and other roads and railroad tracks to get to the breeding around along the Willamette, and then relocating them back across the roadway to the upland. You can see some stats of the group’s work from 2013-2021. The work has continued, and Oregon Field Guide recently did a story on this year’s Frog Taxi, which provides a great overview of the process the volunteers undertake to save this remnant population of red-legged frogs.

Taxi to Where?

Making it across the barrier alone or via taxi only solves one part of the equation. To fully connect the life cycle, viable habitat conditions need to be provided for suitable breeding conditions on the waterside. The landscape of the entire edge of the area used to include the multiple connected ecosystems lakes along a long riverfront edge, including Guild’s, Kitteridge’s, and Doane’s, which is notable as their surrounding wetland margins have been impacted.

Once the frogs can reach the site, the original habitat must be restored to provide suitable conditions. Currently owned by PGE, the taxi “drop-off’“ site is the locus of additional restoration efforts, as noted from the PGE site related to the Harborton Habitat Project:

“The site is one of the largest known breeding grounds for northern red-legged frogs, an amphibian species classified as “sensitive” by the state of Oregon and a “species of concern” under Federal listing status. Additionally, the property is situated where the Willamette River meets Multnomah Channel – a perfect spot for juvenile salmon to rest and find food on their way to the Pacific Ocean.”

Harborton Habitat Restoration (via PGE)

The overall goal is to move from taxi service to more uninterrupted connections from the upland forest to the pools to eliminate the game of Frogger, as well as eliminate the need for volunteers to fill the role of taxi drivers. The next iteration involves increasing overall habitat mobility through an amphibian tunnel that will funnel the frogs along the edges and allow them to move under the roadways and rail lines, connecting Forest Park directly to Harborton. As noted, the Harborton Frog Crossing Project proposed this new connection:

“In an effort to save the dwindling frog population, local wildlife officials and the Oregon Wildlife Foundation have proposed to build a highway underpass to grant the amphibians safe passage. The project calls for a concrete culvert beneath Northwest St. Helens Road and Marina Way to help the frogs reach their preferred breeding grounds.”

Other studies are helping pinpoint more specifics related to the locations and magnitude of the problem. There is funding to assess the mortality of the frog populations is underway by Northwest Ecological Research Institute (NERI), and funded by the Oregon Conservation & Recreation Fund Projects and the Oregon Zoo. The specific goals hope to inform the amphibian tunnel, as they state:

“A wildlife undercrossing and/or creating improved wetland spaces that do not require road crossings are the primary proposed solutions. These are expensive, infrastructure-based solutions, and more data is required to find the most appropriate path forward. Specifically, increased data on the rate and location of frogs being killed at road crossings will inform timing and movement patterns to find the best solution.”

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Wildlife Ways

The Oregon Wildlife Corridor Action Plan (ODFW, January 2024) notes that there are naturally occurring barriers to wildlife movement, but the most critical are human-caused barriers that block movement. Within the context, they also discuss how barriers are relative to species, as quoted:

“The most readily apparent human-caused barriers to animal movement are the physical structures that impede or outright prevent connectivity, such as buildings, fences, roadways, solar developments, and dams. The response of wildlife to structures varies by structure type and by species. For example, a fox may be able to make its way around a large industrial complex, whereas for a frog the complex might represent an impassable barrier. While not all physical structures will completely block animal movement, these features are often associated with increased risk of mortality for wildlife due to collisions, entanglement, entrapment, and persecution. Two of the most prevalent physical impediments to wildlife connectivity are roadways and fencing.”

Wildlife crossings, in general, are gaining momentum with various overpass and underpass options that direct and funnel species from habitat areas and provide safe passage through dangerous areas. The focus is often on larger species, specifically deer and elk, here in Oregon, moving between fragmented parcels of land. There is also the potential to reduce vehicle-wildlife collisions, with specific action plans to provide more solutions. These are dynamic opportunities to connect large habitat patches but come at a steep price.

Wildlife Crossing (via Caltrans)

The types of crossings also need to be adapted to the species’ needs. My favorite is the Crab Bridge on Christmas Island in Australia, which provides an almost vertical climb and spans over a roadway to facilitate the migration of red crabs.

Crab Bridge (via Christmas Island National Park)

Another analog is the work being done for fish passage, including strategies for repairing culverts to provide better access for fish, installing tidal gates to better allow movement up and downstream in fluctuating water cycles and implementing fish screens to limit access to certain waterways while providing access to certain areas necessary for the species to thrive. These are less visible than the larger wildlife connections; however, they also come at a significantly smaller cost and can be localized to specific species migration corridors.

The amphibian connections are a microcosm of these types of projects. More modest in scale, but growing in popularity, there are numerous examples around the globe of different types of passages that work for different amphibian species. The hope is that these will continue to do some of the necessary repair work for the severed connections between critical hydrological habitats, hopefully helping the Harborton Red-Legged Frog populations survive and thrive and give the taxi drivers a break.

Amphibian Crossing example from Doñana National Park, Spain (via Research Gate)

If you are aware of other examples of strategies being used to allow amphibians or other species to facilitate movement in fragmented landscapes, particularly those that are disconnected from historical waterways via development, I would love to hear about them.

BONUS: HIDDEN HYDROLOGY READINGS

Note: This post was originally posted on Substack on 12/11/24 and added to the Hidden Hydrology website on 04/22/25.

Vancouver Rainways

Jason Kingart, city, climate, creeks, cultural, daylighting, design, ecology, habitat, history, infrastructure, landscape, maps, parks, places, precipitation, streams, vancouver, watershedsLeave a Comment on Vancouver Rainways

The Pacific Northwest has long been one of the innovation hubs for green infrastructure solutions. Portland, Seattle, and Vancouver have been leaders for over two decades in developing innovative options to manage stormwater in urban environments, creating decentralized solutions such as green streets, rain gardens, green roofs, and permeable pavings that have now become standard solutions and spread widely to regions.

In places with high rainfall, the initial drivers for these solutions were managing stormwater and reducing combined sewer overflows (CSOs) where rain and sewage mix in pipes, which, in extreme events, overflows into waterways creating pollution issues. The importance of green infrastructure has grown to include multifaceted outcomes, helping mitigate climate impacts by reducing flooding and providing shade to reduce urban heat, and providing ‘green’ solutions over ‘grey’, increasing habitat and helping minimize biodiversity loss.

Thinking strategically about where these solutions are built is key to success. Looking beyond site-specific and one-off strategies, the goal is to provide larger overarching frameworks for how these strategies are planned to work together to achieve holistic results, and ways to plan for these interventions. “How Rainways Could Restore ‘Raincouver’” (The Tyee, August 24, 2023) highlights some of the recent work in Vancouver. What they refer to as ‘Rainways’ are the green infrastructure interventions that have been proposed by City and community groups going back to 2012 built around water in the city and ways to discover and celebrate it.

St. George Rainway illustration (City of Vancouver, The Tyee)

The St. George Rainway is another precursor to some of the work. It was studied and determined that true creek daylighting would be a challenge, due to infrastructure and costs, however, there were other ways to functionally and metaphorically restore the essence of buried creeks through green infrastructure and art. Neighbors have implemented several interventions, including street murals that follow the meandering route of the old creek.

St George Rainway Street Mural (St George Rainway Project)

To further visualize the potential benefits, the team here are some good before and after visuals on the site, transforming asphalt into rain gardens with pathways and plantings.

Visualization of Rainway along 12th Avenue to Broadway (St. George Rainway)

Rain City Strategy

For a deep dive, the Rain City Strategy is a comprehensive document published in 2019 to celebrate water and address environmental and social challenges. The basis is green infrastructure in the city, using streets and public spaces, buildings and sites, and parks and beaches. The overall goals are water quality, resilience, and livability. This includes the management of stormwater to protect and increase water quality, facilitate infiltration, and become more adaptable to climate impacts by mitigating flooding. Beyond function, creating spaces that provide equitable access to nature and benefits to the community are inherent in solutions, assuring they aren’t just solving one problem but many.

Rain City Vancouver (City of Vancouver)

The report includes references to the original buried and disappeared streams that existed before urbanization. These maps build on the work going back almost 50 years to research done by Sharon Proctor in her book ‘Vancouver’s Old Streams’, published in 1978 with a sweet hand-drawn version of the map below (read more about this in my 2016 post “Vancouver’s Secret Waterways”).

The execution of more formal St George Rainway design concepts is available from 2022, showing how the concepts are applied to the segments of St. George Street, with plans and sketches illuminating the proposed condition.

Concept Design – St. George Rainway (City of Vancouver)

The holistic proposal of looking at the macro-level buried rivers as the genesis for these community interventions. The benefits of the designs are manifold, as noted in the project summary:

  • Reduce street flooding
  • Treat rainwater pollutants from roadways
  • Reduce combined sewer overflows into local waterways
  • Enhance climate resiliency
  • Increase biodiversity
  • Cool the neighbourhood during summer heat

CODA

It’s great to see this connection between hidden hydrology and innovative stormwater solutions take shape in such an intentional way. In the past, cities have looked at these buried stream routes in locating facilities and creating smaller sub-watersheds. For some background, in a presentation back in 2006 at the National ASLA conference, I did a presentation entitled “Neighborsheds for Green Infrastructure”, where I made a case for using the routing of buried streams as a framework to implement green infrastructure solutions in Portland, Oregon. I’ll dig up some of these ideas and repost them, as they may be worth revisiting, in the meantime, I mention it in part of my introductory “Ecological Inspirations” post at HH (see image below). Stay tuned for more on this.

Neighborshed Diagram from 2006 in Portland (Jason King)

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Note: This post was originally posted on Substack on 05/03/24 and added to the Hidden Hydrology website on 04/23/25.

The Lost Suburbs of Los Angeles

Jason Kingarchaeology, case study, city, creeks, cultural, ecology, habitat, history, infrastructure, landscape, los angeles, maps, research, streams, watershedsLeave a Comment on The Lost Suburbs of Los Angeles

Strong connections exist between hidden hydrology and the larger work of historical ecology, in terms of methodology and the work to piece together complete stories from fragments of disparate sources. Often the traces of historical waterways inform the larger ecological patterns of places to establish baseline conditions, and historic vegetation patterns, and begin to establish markers to document change. The overlay of indigenous occupation is an additional element, however, it is often hard to reconstruct due to a lack of physical documentation. Examples of projects successfully implementing this type of work are valuable case studies.

A recent article, “Tribal leaders and researchers have mapped the ancient ‘lost suburbs’ of Los Angeles” (Los Angeles Times, October 9, 2023) explores a successful process, highlighting work by groups using these techniques to study six village sites in the greater Los Angeles region. These “lost suburbs”, in this case, are the original settlements and villages within the LA Basin, where, as noted in the article, “…culture thrived here for thousands of years amid a landscape of oak and walnut woodlands riven with waterways teeming with steelhead trout and prowled by wolves and grizzly bears.”

Ancient routes and key village locations (LA Times)

Three tribes, the Chumash, Tataviam, and Kizh-Gabrieleño collaborated with diverse interdisciplinary academic researchers to piece together a tapestry of inhabitation, as noted in the LA Times article by one of the project leads, UCLA’s Travis Longcore: “We had to dig deep for evidence of the great society buried under our modern empire of terraced and graded slopes, rivers sheathed in concrete, industrial development, freeways and sprawl.” 

These provide a trail of evidence to follow for appropriate ecological restoration and responses to climate change. Hidden hydrology is one essential key to the understanding of these ancient places. From the LA Times: “One map reveals the locations of streams, wetlands, vernal pools, and tidal flats that were buried or drastically altered to accommodate urban development.”

Comparison of development impacts on waterways (LA Times)

This is a part of the full historical ecology of the region discussed in the following section. Understanding the pre-colonization waterways allows for restoring places informed by an authentic indigenous history. As noted by Matt Vestuto, one of the collaborators from the Barbareno/Ventureno Band of Mission Indians:

“…the mapping project offers hope for a long overdue reappraisal of Native American history… Almost overnight, we were disenfranchised from the landscape — but our people are still here… now, the challenge is to restore the environment, and rebuild our nations.”

The project is part of a larger Los Angeles Landscape History project, with a report published in 2023 outlining the details of this analysis of the Indigenous Landscape of the city. A key component of the analysis is mentioned in the Executive Summary:

“Descriptions of the historical landscape patterns and function have led to a conclusion that this landscape and region cannot be understood without listening to the stories of Indigenous people who managed this land and thrived for thousands of years before the arrival of European settlers.”

A key part of the work is cartographic regressions, which include reconstruction of the topographic history and hydrological patterns using old maps, aerial photography, and other archival sources, like texts, drawings, place names, historical accounts, and archaeological work. The analyses look closely at trade networks, historical flora and fauna distributions, and their impact on habitat, and provide the blueprint for future restoration. As noted in the Executive Summary:

“This project is unique because a commonly shared, detailed map of the historical ecology—the flora, fauna, hydrology, and landforms, that evolved within Southern California’s Mediterranean climate over millennia and supported human populations for 9,000 years, has never been developed.  Individually and cumulatively, the results of this research are vital resources to all regional and local planning efforts involving sustainability, habitat restoration, and preparing for climate change.”

Story Maps

An interactive Story Map is also worth checking out, providing a visual executive summary of the report. Focusing on the section related to Historical Water Features, the team traces stream routes in intervals, including 1896-1903 and 1924-1941, with the ability to compare, via slider, the two time periods as shown below, and highlights the radical change of regional hydrological patterns as the city developed.

Historical Water Features 1896-1903 (LALAH Story Map)
Historical Water Features 1924-1941 (LALAH Story Map)

The citywide mapping of vegetation types is directly related to these original historical waterways, and an interactive map, based on the Military Grid Reference System (MGRS), using a 1km grid, to provide map data in cells of potential natural vegetation (PNV). This is described in the Story Map as the “…vegetation that would develop in a particular ecological zone or environment, assuming the conditions of flora and fauna to be natural, if the action of man on the vegetation mantle stopped and in the absence of substantial alteration in present climatic conditions.”

Map of Hypothesized Potential Natural Vegetation of the Los Angeles Region (LALAH Story Map)

The connections between hidden hydrology, historical ecology, and indigenous occupation are more than just understanding the past. As the researchers point out, the ability to employ this data for solutions to loss of biodiversity, climate change impacts, and other challenges, while celebrating the cultural legacy of place, is key. There’s a wealth of information worth studying this model in more depth, to better understand the Los Angeles Basin ecology and hydrology and to refine and adapt this approach to other regions, specifically centering Indigenous stories as a key component in historical ecology work.

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Note: This post was originally posted on Substack on 05/01/24 and added to the Hidden Hydrology website on 04/23/25.

Restoring Swede Hollow

Jason Kingcase study, city, creeks, cultural, daylighting, design, history, infrastructure, places, projects, watersheds1 Comment on Restoring Swede Hollow

An interesting project in St. Paul, Minnesota emerged in this Star Tribune article “Work could begin soon to bring St. Paul’s Phalen Creek back to the surface,” which highlights the mix of ecological and cultural benefits of urban stream daylighting. Through a focus on both the benefits to wildlife habitat and ecosystem function and the connection of cultural heritage for native people and early immigrants to the area, it shows a rich story that is told through multiple lenses to provide solid rationale for daylighting projects.

One major idea of daylighting is visibility. As mentioned in the Star Tribune article, this is a typical case of burial of creeks for development, but like many other areas, the perceptions have shifted and the value of historical waterways are being restored. A big part of that is pointed out by Ramsey-Washington Metro district watershed project manager Paige Ahlborg, watershed project: “Another benefit is just restoring a community’s connection to the water,” Ahlborg said. “Seeing it makes it harder to do things that harm it. We still have a number of people who think that ‘if I put something down the [storm]sewer drain, it will be treated.'”

The history of places is expressed in place names. From the Capitol Region Watershed District site, some history on the current name: “Swede Hollow on the City of Saint Paul’s East Side is a historic immigrant neighborhood dating back to the 19th century. This lowland valley includes a portion of a stream from Phalen Creek to the Mississippi River. After housing was removed following the turn of the century, the city created Swede Hollow Park and placed some of the stream flow in a storm sewer pipe to complete its path to the river.”

Image of Phalen Creek burial in the 1920s. – via Minnesota Historical Society

As is the case with most places, the story and names is often told in European terms (i.e. Swede Hollow). The creek name as well comes from Edward Phalen, one of Saint Paul’s original colonists, who settled on the banks of the creek in 1838. Prior to this arrival, the history of place stretched far earlier as referenced in the Lower Phalen Creek Project, a native-led project:

“This creek served as a corridor for the Dakota people who lived here, as they made their way up the chain of lakes by canoe to White Bear Lake – one of many areas where they gathered wild rice.”

The daylighting has both ecological and cultural benefits. In the Star Tribune, Lower Phalen Creek Project Executive Direction Maggie Lorenz, who is both Dakota and Ojibwe, mentions: “[Phalen Creek] is an essential part of the community — it will bring more natural habitat and it means more opportunities for recreation and stormwater management. And, from a cultural perspective, we are really interested in restoring the land and taking care of the land according to our traditional teachings.”

While the goal is to extend daylighting all the way to the Mississippi River, one the first legs connects from Lake Phalen and Maryland Avenue as shown in this enlarged plan, highlighting the ecological benefits, including fish passage and enhanced in-stream habitat, establishment not just of the creek but adjacent floodplain wetlands to provide resilience and habitat for amphibians, and upland prairies that provide native riparian habitat supporting birds and pollinators.

“Consultants at Inter-Fluve, Inc. produced this visual to represent the proposed location, general design elements, and predicted habitat benefits of a restored stream channel of Phalen Creek at the Lake Phalen / Maryland Avenue project site.” via Lower Phalen Creek Project

A ton of additional information is at the LPCP site, including graphic summary of the project is found in a brochure that connects the dots between the cultural and ecological.

Brochure for Daylighting Phalen Creek – via Lower Phalen Creek Project – click here for full size PDF

Header Image: “Rendering of a daylighted creek provided by Capitol Region Watershed District.” via Lower Phalen Creek Project

Anne Whiston Spirn’s Legacy in Philadelphia

Jason Kingcase study, city, climate, creeks, cultural, design, ecology, history, infrastructure, landscape, maps, philadelphia, places, precedents, streams, watershedsLeave a Comment on Anne Whiston Spirn’s Legacy in Philadelphia

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

Draining Seattle Small Lakes

Jason Kingcity, creeks, history, infrastructure, lakes, maps, parks, seattle, streams, watersheds13 Comments on Draining Seattle Small Lakes

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.

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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

 

 

Washington Water Toponyms

Jason Kingcreeks, landscape, language, maps, places, rivers, streams, washington, watershedsLeave a Comment on Washington Water Toponyms

I’ve been inspired by the work many others have done to capture the qualities of coverage of waterways at national scale both in the US and the UK, and beyond the mapping, appreciate their investigations into the unique distribution of place names, or toponyms.  The language of the waterways informs more local hidden hydrology endeavors, and understanding regional vernacular variations provides a snapshot into our varied relationships with water.  While a glance at the Pacific Northwest via these other maps shows that the predominant name for waterways is probably going to be either creek or river, I wanted to dive a bit deeper to see what other names are used to denote waterways.  To accomplish this, I spent some quality time with the USGS National Hydrography Dataset (NHD) to unlock a bit of the secrets of regional variations.

For starters, the NHD is an amazing resource of information, pulling together a comprehensive collection of data on flowlines, watershed basins, and more and the ability to get data from a variety of formats for small to large basins and states.  From their site, the purpose of the data is to: “define the spatial locations of surface waters. The NHD contains features such as lakes, ponds, streams, rivers, canals, dams, and stream gages, in a relational database model system (RDBMS). These data are designed to be used in general mapping and in the analysis of surface water systems.”  The first steps are a bit daunting, as the State of Washington included data with over 1.3 million flowlines, seen below in aggregate. The flowlines aren’t any one single waterway, but are the individual segments that make up each creek.

While the data preserves local basins shapes by sprawling outside state lines, I wanted to make this unique to Washington, so needed to clip it to the state boundary.  This ended up being a bit of a task for my rather slow computer to crank out the clipping, so I had to think of some alternatives to simplify the dataset.  Interestingly enough, over 80 percent of the flowlines (around 1.1 million of them) are unnamed, and while I’m sure are perfectly lovely bits of creek and river, they don’t help in our purpose in terms of deriving place names.  Eliminating them also serves the dual benefit of reducing the size of our working dataset quite a bit.  After trimming to the state boundaries, we ended up with a nice workable set of around 170,000 flowlines that have names, seen below.

Per the NHD FAQ page, “Many features also are labeled with the geographic name of the feature, such as the Ohio River. The feature names must be approved by the Board of Geographic Names (BGN) in order to qualify for inclusion in the NHD.”  More on the BGN and the wonderful assortment of place names that exist in these lists beyond their descriptor (which is perhaps the fuller idea of toponyms), in this case we break down the list and see what comes to the top.   Not surprising, but the use of the terms Creek and River dominate the landscape of Washington, accounting for 98% of all named flowlines.

Of the totals, creeks truly dominate, with around a 75% chance that a trickle of water in the state will be referred to as a creek.  The larger, less numerous rivers make up 23% of all flowlines, and the map above paints a wonderful portrait of the density of waters.  Separated out by type, you see the branched structures of trunk and stem that pumps water through most of the mountainous west side of the state, with the larger, drier plains to the east more open.  All total the combined length of these equals over 30,000 linear miles.

1. CREEKS

2. RIVERS

So we live in a creek and river area of the world.  Amidst these dominating toponyms are a distributed layer of types of flowlines that make up the remainder of the story of Washington, that final 2 percent, emphasized in a darker blue below.

The secondary naming of these includes the most common, isolated and color coded, with a legend denoting the eight most common alternative flowline names.

The relative percentage as a portion of that slim 2% of state flowlines, include:

  1. Slough (30%)
  2. Fork (16%)
  3. Canal (16%)
  4. Ditch (9%)
  5. Wasteway (4%)
  6. Branch (4%)
  7. Run (4%)
  8. Stream (3%)

The remaining 14% are composed of small portions that include Lateral, Brook, Drain, Slu (a variation of Slough), Gulch, Channel, Siphon and it’s alternative spelling Syphon, Washout, Waterway, Swale, Glade, Pass, Gate, and Range.  Many of these as we see, are geographically located towards the center of the state where agricultural landscape has created larger modifications and creation of waterways (described in the NHD data under the names like Artificial Path, Canal Ditch, and Connector).  There’s a split between more traditional waterway name variations (i.e. Slough, Fork, Branch, Run, Stream) and those that mostly utilitarian, capturing the poetry of industrialization (i.e. Wasteway, Ditch, Canal, Siphon, Lateral).  Removing the background landform, you see the composite of the different stream types as a whole, with creek/river in blue and the remainder by color.

For a more local view, the NHD data is a bit less sparse, not capturing the same amount of complexity is smaller urban waterways, plus without the other water bodies like lakes the geography seems somewhat off.  The purple to the west in the Olympic Pennisula shows a density of flowlines referred to as streams, and the darker red denotes a number of local sloughs that exist in local river systems.  It’s harder to see, but you can catch the Ship Canal in this group, and the slightly lighter red fork in the center is the infamous Duwamish Waterway, the lower stretch that runs through Seattle and ‘lost’ its designation as a river – interestingly enough it’s the only flowline in the state with that moniker.

I was expecting the dominance of creeks and rivers in the nomenclature, but was also really surprised that these combined to make up so many of the collective flowlines. Perhaps early settlers and place-namers lacking a bit of creativity.  It was also a good surprise to find a wealth of other place names in Washington, albeit many used to describe man-made features, including the most poetic name of wasteway, but enough fun to find an occasional branch, fork, brook, and run, which are more common elsewhere in the United States, per the other US maps.

These are pretty basic graphics exported from GIS just to give a feel for the data, so I’d like to play around more with representation, perhaps some sort of heatmap.  Also I’m eyeing Oregon for a comparison, and maybe wanting to dive into the waterbodies as well beyond linear flowlines, so more fun to come.  Who knows, an atlas of the whole country with a top ten of their most common names of each state.  Or maybe not…

HEADER:  Excerpt of River and Stream Composite Map – data from ESRI, NOAA, USGS – Mapping by Jason King – (all maps in post same attribution, © Jason King, Hidden Hydrology, 2018)

Disappearing Rivers of the US West

Jason Kingcreeks, drinking water, infrastructure, maps, rivers, streams, watershedsLeave a Comment on Disappearing Rivers of the US West

An interesting project from Center for American Progress, The Disappearing West “maps a rapidly changing landscape, explores what is being lost, and profiles a new movement for conservation that is gaining ground.”  The project documents both land and rivers, with an eye on the impacts of development (urban, dams, mines, and more) on these systems, and provides data and maps on their current conditions.  From a water point of view, this information provides a new level of detail on river health in the Western United states.

“Through the Disappearing Rivers project, the Center for American Progress is providing the first comprehensive snapshot of the condition of Western rivers. “

The documentation is compelling, and punctuated with some fun graphics, as seen in the amount of rivers modified from their natural states, including levels of headwaters, smaller rivers and streams, and major rivers. The results are staggering. “Often portrayed as continuous lines on a map, modern-day rivers are fragmented and impaired versions of their former selves. Waterways that once supported navigation and enabled adventurers to explore the West are no longer passable in their entirety. In fact, the average length of a river in the West has been reduced by 84 percent.”  

And some of the graphics have a bit of whimsy – highlighting the impacts of dams on fish… and reinforcing what we already knew, that it is oh, so very sad that they just wait, and wait for that dam to be removed.

The maps as part of this project are the focus of what I wanted to include, as they are compelling visually.  I first heard of this project via Twitter, from a link from the mapmaker John Gage from Gage Cartographics, (via Twitter @gageCarto) who described using 400,000 flowlines from the National Hydrography Dataset to create the mapping for the entire west coast (see header image above) with layers of embedded data using the amazing suite of tools from Mapbox GL.  Stream-level data, like this snapshot of the Portland area and extent of floodplain alteration, sit on a dark background for good contrast, and shift with a gradient from red (high degrees of alteration) to blue (low degree), and highlighting the impacts of urban development on rivers and streams in a beautifully tragic way.

The same view, again of Portland, showing flow restriction, which is less problematic, but is highlighted with some key spots, interestingly enough the outflow from the Sandy River east of Portland.

Larger, thematic maps provide watershed and other coverage, including extent of floodplain alteration. As you can see from the Seattle image below, the extent of alteration of urban floodplains, not surprisingly, is greatest in urban areas, and the Salish Sea coastal areas show up to 90-100% levels of alteration.

There’s also mapping of dams by size of their capacity, again with a dark background highlighting the point data.

The map functionality allows for selecting layers and different base maps, along with extracting specific information from map elements.

The use of hover pop-ups is great as well, conveying location-specific information such as stream info, or watershed-level data for impacts in Washington like the map below showing irrigated lands.

My focus is on some northwest zones, but the project spans the entire west, and there’s also an animated tour of the Colorado River, which employs some interesting story mapping techniques.  The animated slides take you through the story of what is “…Sometimes called ‘America’s hardest working river,'” and describes the conditions that cause “…over half (54%) of the Colorado River is dammed, diverted or otherwise altered from its natural state.”  Using a number of different maps themes, views, and animations, along with text and photos, it paints a compelling story of the impacts of the river, including a major impact, dams.

There’s a ton of info, including links to download the map data as well, via a site for the Disappearing Rivers of the Western United States, which “Disappearing Rivers is the culmination of an analysis by Conservation Science Partners, in association with the Center for American Progress, to investigate how human development has altered rivers in the eleven western states. The objective of Disappearing Rivers is to quantify the degree to which human activities have altered rivers in the western US. We separated this objective into two primary components: flow alteration and floodplain alteration. The Disappearing Rivers gallery contains river and stream flowlines data with associated flow and floodplain alteration attributes.”  The site is loaded with good info, and the maps and graphics help tell a compelling story that complements the data.  The power of maps, and the overall ability to convey tons of information on easy to use, online maps, still blows me away.  Check this out – worth some time.

HEADER: Snapshot of West Coast Flow Restriction – Disappearing Rivers

Watershed as Political Boundary

Jason Kinghistory, infrastructure, maps, places, rivers, streams, watersheds5 Comments on Watershed as Political Boundary

A recent announcement that the Department of Interior is planning a massive reorganization has received a bunch of attention.  While Secretary Zinke has done a number of dubious things in his short time at Interior, this one at least, having some origins based on the concepts of John Wesley Powell, initially made me pause to consider if it may have merit.  If you can stomach watching Zinke talk for over five minutes, the video from DOI explaining the move is here. Or you can read this, where I first read about the concept, via an article Outside Magazine:  “Ryan Zinke’s Watershed Plan Is 140 Years Too Late”  To summarize the background:

“The latest object of the interior secretary’s affection is John Wesley Powell. A Civil War veteran who lost his right arm at the Battle of Shiloh, Powell is best known as a geologist and geographer who led expeditions in the American Southwest, including the first documented float down Grand Canyon. Those travels inspired Powell, in an 1878 report, to recommend the West be settled in a fashion that would organize the desiccated territory by watershed. Doing so, he argued, would make for a more collaborative and ecologically sound way of managing resources, especially in a region where the most precious resource is water. “

This basin map, seen below from an old NPR story about “The Vision of John Wesley Powell“, shows the “Map of the Arid Region of the United States showing drainage districts, 1890-91”, which is the impetus mentioned by Zinke, and explained per the article: “In 1878, Powell published his Report on the Lands of the Arid Region, which laid out a concrete strategy for settling the West without fighting over scarce water. Powell wanted to stall the waves of homesteaders moving across the plains and mountains. Instead, he wanted to plan settlement based in part on the cooperative model practiced in Utah by Mormon settlers, who tapped mountain snowmelt and the streams, lakes and rivers it created with irrigation ditches leading to crops. Powell wanted to organize settlements around water and watersheds, which would force water users to conserve the scarce resource, because overuse or pollution would hurt everyone in the watershed. Powell believed this arrangement would also make communities better prepared to deal with attempts to usurp their water.”

While some see it as pure politics, and view it with skepticism, others acknowledge some merit. Per Outside: ““Intellectually, the idea of organizing more in terms of the landscape in the West—that works,” says John Freemuth, executive director of the Cecil D. Andrus Center for Public Policy at Boise State University. “But the devil is in the details. The damage that could be done to relationships and how agencies do business, that doesn’t look like it’s been well thought out yet.”  There is mention of the complications of the current water system, where far away water is transported hundreds of miles to other locations, which perhaps makes basin boundaries obsolete, and is antithetical, in essence to Powell’s original notions, (thus the ‘too late’ tagline). As mentioned. ““For Powell, the water would not be taken out of the watershed or out of the basin and transferred across mountains…hundreds of miles away to allow urban growth to take place,” Donald Worster, a Powell biographer, told NPR in 2003. “So L.A., if it existed at all, would have been a much, much smaller entity. Salt Lake City would be smaller. Phoenix would probably not even exist.”

The Washington Post also weighed in, mentioning on January 10th the “Interior plans to move thousands of workers in the biggest reorganization in its history”, and some of the implications of “the largest reorganization in the department’s 168-year history, moving to shift tens of thousands of workers to new locations and change the way the federal government manages more than 500 million acres of land and water across the country.”  In short, the “…proposal would divide the United States into 13 regions and centralize authority for different parts of Interior within those boundaries. The regions would be defined by watersheds and geographic basins, rather than individual states and the current boundaries that now guide Interior’s operations”.

Skeptics are probably right to wonder if this is an effective change, but some of the criticism of it being hard to do, moving offices, costs, issues like splitting states into two zones sort of miss the point, if the goal is a broad basin-specific planning mechanism.  The concept that there’s a political agenda is obvious, and some of the talk of this being a covert way of downsizing government and eroding the mission are valid.  Other criticisms, such as removal of Bureau of Indian Affairs offices, as mentioned in the article are more troubling.  As quoted: “This proposal is concerning because it appears to eliminate the Navajo Regional Office of the Bureau of Indian Affairs,” said  Sen. Martin Heinrich (D-N.M.). “A change of this magnitude should only come after extensive, meaningful government-to-government consultation with the affected tribes.  On its face, this looks more like a dismantling than a reorganization.”

Environmental groups as well echo the idea that it may seem ok on the surface, but is at it’s root political.  As quoted: ““A regional approach to managing Interior might indeed make sense, but the jury is out on this reorganization,” Sharon Buccino, senior director for lands at the Natural Resources Defense Council, said in an email. “Virtually everything Secretary Zinke has done to date has been to advance fossil fuel interests — above the stewardship of our public lands, preservation of wildlife and protection of clean air and water.””

It’s dubious whether this would happen, but there’s some intriguing notions it brings up, perhaps in a less divisive political climate, as to where this could actually be beneficial.  The Washington Post article linked to the overlay of current bureau configurations and the proposed idea of ‘Common Regions’, as mentioned.  The patchwork of overlaid jurisdictional boundaries would obviously be a change, but fundamentally there’s some wisdom (perhaps Powell’s wisdom) at work in thinking about this

Whether it goes anywhere is dubious, as it’s an interesting idea wrapped up in massive government reorganization that brings with it so much baggage as to sink it before it starts. As Outside concludes, “Perhaps it’s best to think of Zinke’s watershed-based West as a thought experiment.”   Or possibly, it’s a question of being too soon, and that a more thought-out approach could possibly be implemented over the course of the next decade to address concerns but keep it from just being that unrealized concept.

BEYOND POLITICS

I’ve long been a proponent of the concept of transforming political boundaries more in line with hydrological ones, as the idea of connecting choices made with the impacts to watersheds, first presenting the concept in a presentation at the 2006 National ASLA Conference.  The genesis of the idea is the that these basins and watersheds are nested systems, with larger units encompassing many smaller elements, and in turn being encompassed by larger systems. The idea of neighborsheds (i.e. neighborhood watersheds) involve a small scale redrawing our local boundaries using subwatersheds instead of arbitrary street or orthagonal boundaries that we currently employ.  This provides an opportunity to reimagine our local places in alignment with nature, and also helps residents understand their place at a scale that is knowable.  The connection to local flows provides a context, and the nesting systems allow one to link thier actions to the larger whole.

There are some obvious organizational structures in place that adopt this nested, such as the idea of USGS Hydrologic Units (HU) that organize elements like the Watershed Boundaries used in the National Hydrography Database.  The map below shows the largest resolution, the regional scale, of which there are 21 in the United States, know by a system of codes, or HUCs.

Some info via a really good page on Wikipedia on Hydrological Codes, this scales down from the original 21 regional HUs, to 222 subregions, 370 basins, 2,200 subbasins, 22,000 watersheds and around 160,000 subwatersheds.   The range in scale is also interesting, with a Region averaging a size of approximately 177,560 square miles, a typical basin spanning 10,000 square miles, down to 220 square mile watersheds and 40 square mile subwatersheds.  The Pacific Northwest is HU-17 expands to grab most of the Columbia River basin flowing west from the Rocky Mountains (which also reaches far up into Canada but is not shown on this map).

This breakdown the the nested scales provides a nice summary of that breakdown.

 

The Water Resource Inventory Area (WRIA) structure in Washington is an extension of this idea as well, with the ability to delineate a watershed focus on conservation. An image of WRIA boundaries overlaid with county lines in Washington State is instructive as to the difference between political lines drawn.

These denote the smallest HU scale of subwatershed, which as we discussed are around 40 square miles each, which is still rather large, but at least somewhat more comprehensible than larger basins. The WRIAs for the Puget Sound show the very organic structure of basin-focused districts (which is also the final scale of the Hydrological Unit map showing Subwatersheds), with the only hard-line in this case being the Canadian border to the north.

An zoomed into the smaller scale around Seattle, the two districts include WRIA 8, the Lake Washington and the Cedar River Basin, which encompasses much of the City, and the WRIA 9, the Duwamish-Green River Basin which drains the south segment of the city.  While it may complicate things as a current city and a county boundaries and require some intergovernmental agreements from many parties, the ability to isolate hydrological areas makes planning for these watersheds in terms of impacts to ecosystems much easier.  In some sense these could be a reimagined county structure by these subwatersheds, which isn’t actually a bad idea, if only as a though experiment.


The nesting could continue infinitely and get down unit you get to the smallest drainage, which could encompass a few blocks in the city.  More on this to comes as I continue to expand on the neighborshed concept. While the politicized proposal from Interior seems doomed to failure, there is some merit to these types of proposals that transcend politics and assess the concept of watershed specific boundaries in terms of thinking outside the box, and inside the basin.

HEADER:  Image of Powell’s Arid Lands Map – via Outside Magazine