Past Forward: Mannahatta

I may have mentioned my love of historic urban maps. If not, then I will plead guilty here, and offer up Strange Maps as a vital modern contribution to our historical heritage, and let slip fact that I've read most of the written works of Mark Monmonier. As objects, maps are fascinating artifacts. Even more interesting is using these remnants of history to attempt to visualize and recreate a baseline, whether that be social, ecological, or other. A small past project started to delve into this in Portland - looking at maps of historical and 'disappeared' streams to evokes some of the cities hidden hydrology. I'm currently evolving this idea in an essay, so look forward to more on this in the future.

The work of Dr. Eric Sanderson and the Mannahatta Project takes this concept to a whole new level. The introduction to this project for me came while reading 'The World Without Us' towards the end of 2007. My reactions to the schizophrenic nature of the book notwithstanding, I was totally drawn into the chapter on Mannahatta, in method and vision. Today, Treehugger profiled this project, featuring a talk by Sanderson and a range of visuals to provide a vision for what is now New York City - of over 400 years ago. The study begins with analysis of historical maps:


:: 1782 British Headquarters Map Detail - image via the New Yorker


:: 1819 Farm Maps - image via the New Yorker

Mannahatta, which is derived from the indigenous Lenni Lenape tribal name for the land, seemed historically to burst with diversity. As Treehugger mentions in the lecture, Sanderson equated the beauty of Mannahatta as equal or greater than that of Yellowstone or Yosemite, and that it: "...was more biologically diverse than either of those two areas, and with its hardwood forests, freshwater, and estuarine environments, Mannahatta’s 54 different ecological communities (that is, interacting species living in the same place, bound together by a network of influences) and lush greenery would have dazzled any nature lover."


:: Mannahatta, circa 1609 (with current landform outline) - image via the New Yorker



:: Collect Pond (now Foley Square) - image via the New Yorker

Another resource is an audio interview with Sanderson on the Wildlife Conservation Society site, as well as some fact sheets and link to a fascinating paper authored by Sanderson and Marianne Brown entitled 'Mannahatta: An Ecological First Look at the Manhattan Landscape Prior to Henry Hudson'.


:: Lower Manhattan - image via the New Yorker

Sanderson took the early mapping, along with a computer program named 'Muir webs' to piece together the hidden puzzle of the geology, topography, hydrology and ecology of early 1600's Manhattan. Quoted via Treehugger:

"Sanderson is using his program to map what would have existed on each city block in Mannahatta 400 years ago. The program works through a process of matching animals to their habitats and vice-versa. By knowing that a certain animal species existed in an area of Manhattan and knowing what that animal ate, Sanderson can predict through the Muir webs program what plants or soils would have been there as well, or conversely can use knowledge of plants and soils to discover what animals would have found a habitat in any specific area."

One issue with the visuals is a lack of immediate context - kind of a vagueness of 'nature shot's without seeing the 'before and after' shots of landscape and city together. Plans are in the works to provide the ability to juxtapose old and new maps, and the entire endeavor will be well documented in time for the 400 year anniversary of Hudson's voyage to the area in 2009. Here's an example of this:


:: Mannahatta + Manhattan (Times Square then and now) - image via the New Yorker

As I mentioned, it's interesting to see the major changes in our urbanism - as well as to see the fact that the inherent nature of place is difficult if not impossible to erase. Coming full circle, back to a bit later date in history - is the map that I first encountered - the Survey Map of 1852 shows an early pioneer Portland in it's fledgling, even pre-Stumptown days. Focussing on waterways and topography, it's interesting to see what was hidden, yet how much still remains of this hydrology.


:: Survey Map of Portland (1852) - image via Portland BES


:: Detail of the Survey Map of Portland showing downtown - image via Portland BES

From a pure restoration point-of-view - there's little hope in recreated Mannahatta (or even less dense more verdant Pioneer Portland for that matter). Our challenge is to learn from these studies - what was there, what was the predevelopment baseline for water, habitat, and tree cover, then aim to recreate these functions. This can be physically (through selected ecological restoration), functionally (through green roofs, nature parks, habitat gardens, streettree canopy, green streets), and metaphorically (through art, interpretation, poetry and beauty).

This is our way of taking the past, learning from it, and moving forward a little more wise than when we began.