A couple writers I like have been having a go-round about the 606. Which… okay, it sounds like old news. Been there, written that, months ago. But the fact that it's old news is also sort of the point.

The whole thing started when Aaron Renn, aka the Urbanophile—I interviewed him awhile back about the Chicago Riverwalk—returned to Chicago and finally got a chance to see the 606, which he says "fell short of expectations." Which, if your expectations were those set by Deputy Mayor Steve Koch—"This is the High Line on steroids"; "a concept far beyond that truly transformative project"; "people are going to come from all over the globe"—sure, it's not Xanadu.

But the 606 has engendered some disappointment. Renn cites Edward Keegan in Crain's, who, in his review of the project, begins by asking "Is that all there is?" The review is more positive than that implies, but I've heard a few of those points commonly—too unambitious, too spare, not High Line enough.

New York's High Line, though, is not a great comparison. Not without some caveats, anyway.

1. The High Line is in the middle of Manhattan.

Lovely as it's designed and kept, much of the awe of the High Line is its surroundings. At one point the High Line even runs runs under a spectacular hotel.

Photography: Whet Moser

Around that stretch you can see the Hudson River.

No knock on Chicago; the High Line wouldn't be the High Line if it ran through Brooklyn or Queens.

I'll give the High Line two vastly superior design elements, though Renn has a point about its high-quality details. One is the 10th Avenue overlook, seen below.

Then you have the rail-mounted lounge chairs.

In both instances you find ample seating options, something the 606 sorely lacks currently. If Chicago wanted to blatantly rip off the High Line, I'd start with the chairs—the overlook may be a bit pricey to replicate. 

2. Efficiency is a design decision.

As Streetsblog Chicago's John Greenfield points out in a response to Renn, the High Line is almost half as long (1.45 miles versus 2.7 miles) and almost twice as expensive (estimated to cost $172 million when it's done, versus $95 million for the 606). Plus it took much longer to build while being opened in three small segments (2009, 2011, and 2014, whereas construction on the 606 began in 2013).

When the 606 opened, people expressed dismay at how minimal the landscaping looked—skinny saplings, wispy grass, open dirt. But the park's leadership didn't want the perfect to be the enemy of the good. It was, and is, a functional transportation corridor. In my personal experience biking it, it's a convenient shortcut that keeps me off the street for almost three miles; I'd much rather have it there than wait until it was pretty enough to debut. You wouldn't wait to open a road until you complete all the landscaping, and the 606 is as much a transportation corridor as it is a park. 

3. Incompleteness is an aesthetic.

Renn acknowledges that the landscaping isn't done. But the landscape architect made an interesting point to me about this. The 606 used to be an industrial-transportation corridor, and they borrowed from the aesthetics of that. Then it started to return to nature, and they borrowed from the aesthetics of that as well.

So as the landscaping of the 606 grows, it's going to follow that path again, ending in a balance between the urban transit system it was and the reclaimed natural landscape that so many illicit users liked about it. "The planting was done through that lens," Matthew Urbanski, the 606's landscape designer, told me. "How is that going to evolve? How are people going to perceive this over time? It’s not so much a set piece, in other words, but a dynamic relationship we’re trying to create, that seems to be more about the passing of time, impermanence and permanence."

Perhaps it's putting lipstick on a process. But I like to look at it as adding the fourth dimension of time to the concept. Either way, my toddler certainly found the construction equipment to be a compelling aspect of the trail. (Any landscape architects who would like to take this germ of an idea should feel free to run with it.)

And time is a central element to the 606. As the lead artist, Francis Whitehead, explained to me, the landscaping serves as a giant data-gathering tool. She was inspired by the Japanese cherry-blossom festival, where the cultural recognition of the blossoming of the trees inadvertently created a valuable climate record stretching back more than a millennium. She hopes to do the same here in Chicago.

For instance, serviceberry trees dot the 606. Here's a good explanation of their climate-tracking capability, courtesy of Grist:

453 apple serviceberry trees will bloom in a wave, spreading east to west over the course of five days, thanks to Chicago’s legendary lake effect, which keeps temperatures cooler near Lake Michigan. Scientists and the public will be able to track the blooming year-to-year, thus keeping a running diary of shifts in climate.

That kind of data will only reveal itself over a brief period every year, and will take generations to output. But that's kind of the point, too.

"I’m hoping that another, deeper kind of understanding of where we are, where we’re going, and what’s happening in front of us can evolve over a very long time," Whitehead told me. "This question of the Japanese cherry blossom that did a certain thing—we won’t know if this is a success before… we’ll all be off the planet before we know. It’s forming a hundred-year artwork. It’s making a proposal that art doesn’t have to deliver itself as an instant experience."

The 606 isn't done. In some ways, as with so many other things, it won't be done for many, many generations, in ways that we won't be around to appreciate.