Saturday, February 22, 2020

Wasatch Front Water, Part 1: Experimentation and Finding Focus

This is the first post in (what should be) a series of posts about my latest map, That the Desert May Blossom as the Rose. Today I'm introducing the map and reviewing the background and inspiration behind it. In the future I'll write a little bit more about the techniques I used to realize different ideas and messages in the map.

Click here for a larger, compressed-quality image

Experimentation
About a year ago, right after fixing my skymodel implementation, I started exploring different options for a map of the Wasatch Front. I find that sometimes I need to just load different datasets and explore them until I get inspiration for a map.

I started with the National Land Cover Dataset (NLCD), which has the potential to be a fun basemap if you can do something with the visually-strong reds they use for urban areas. I sandwiched that between a slope-combined hillshade and a skymodel with strong shadows and got excited about how the mountains looked. I put a roads layer down to help me get my bearings.

Water Flows Downhill
Adding the NHD water basin layer was what gave me my first flash of inspiration for this map. I realized the water basins didn't always line up with my mental map of relationships between areas. It's amazing just how much overland transportation, especially the modern interstate system, hides natural boundaries in our mental maps.



For example, Park City is more related to Ogden, hydrologically speaking, than Salt Lake City. Downtown Park City drains into Silver Creek, which runs into the upper Weber River just below Rockport Reservoir. Kimball Junction and Jeremy Ranch drain into East Canyon and then into the lower Weber River 30 miles downstream. At the top of Parley's summit, the canyons drain down to the Jordan River. Water on the west side of the summit doesn't meet Park City water until the middle of the Great Salt Lake.

If you were to graph out the dendritic drainage structure of the Great Salt Lake Basin, Park City and Kimball Junction would be on hydrologically separate branches despite being physically right next to each other. Parley's Canyon is on completely the opposite side of the trunk, and its branch doesn't meet up until the very end of the graph.



However, my mental relationship map of Park City is almost exclusively focused on I-80 and is completely linear: Salt Lake, Parley's Canyon, Parley's Summit, Jeremy Ranch, Kimball Junction, Park City. Because of how steep the climb up to Parley's Summit is (especially if you've got a 15-year-old four-cylinder station wagon), anything after that is "downhill". The slight elevation difference between Kimball Junction and downtown Park City doesn't even register, but it's enough to send water on two different paths dozens of miles apart.





Deadlines: The Mother of Productivity
Life got busy and months passed before I did anything more with this concept. Finally, at the end of 2019 I saw the announcement that submissions for the 2020 Atlas of Design were due in late January. I thought this map was my best shot, despite still not really having a solid plan. Four weeks to do a map in my spare time? Why not.

Just like photography, a good map needs to have a single focus, a single story it's trying to tell, a single theme it's trying to illuminate. Both photography and cartography are really the art of removing as much extraneous information as possible, similar to the not-really-Einstein quote "make everything as simple as possible, but not simpler." (This also applies to writing, though the length of this post is evidence that I'm much better at simplifying maps than words)


I spent two weeks working on the map with the vague theme of showing the basins. I classified streams, I cleaned up basin boundaries (the NHD doesn't know what to do with the manufactured wetlands in the Jordan River delta), I played with elevation color ramps.

Finding Focus
The NHD flowlines include a couple of major artificial pathways, like the Salt Lake City Aqueduct running from the mouth of Provo Canyon to the mouth of Parley's Canyon. Being an avid user of the Murdock Canal Trail, I knew there were more aqueducts and pipelines that aren't in the NHD. I started hunting down alignments from water conservancy district webpages.

It was after a couple days down this rabbit hole that I realized I was more interested in making a map about all the water works delivering mountain water to the valley cities. This became my new, sharper focus.



I was struck with renewed awe that we move water not just between different branches of the Great Salt Lake Basin (like the Weber-Provo Canal in Kamas) but between the Colorado/Pacific Basin and the Great Basin via the Strawberry and Diamond Fork systems. I wanted to show this, while also showing off the majesty of the Wasatch Front.

So, I guess, in the end, I really have two goals: a) Show the extensive water systems, and b) Show off my hillshading/terrain techniques. I hope that I managed to do b) without impacting a) too much. I can definitely do a different style of map for a), and I've got some ideas for that already.

But for now, such as it is, it is That the Desert May Blossom as the Rose.