This note is posted on behalf of Eymund.
Background for a potential May 11 kite mapping excursion in Prospect Park with Becky Boger and her Brooklyn College students:
As unlikely as it appears while walking along the contaminated shores of the Gowanus, this waterway actually originates as freshwater springs high up on the hill of Prospect Park. See this video of going out and actually finding one of these springs: http://publiclab.org/notes/liz/05-06-2014/video-hunting-for-groundwater-springs
Framing this into a research project
The goal of our Prospect Park wetland's / spring mapping research would be to establish:
a: are Prospect Park artesian springs really there ?
b: are these natural spring outflows currently connected to Prospect Parks internal drainage system, or are they (whoops !) connected to the Park Slope combined sewage system flowing down to the Gowanus?
It should be noted that the new DEP administrator Emily Lloyd was formerly Prospect Park's president and would be keenly interested in anything involving City Park solutions to the $78 million DEP is currently required to spend to solve Gowanus sewer overflow problems.
Below: 1782 Map of Vechtes Brook area in Park Slope with Arc Hydro 2004 stream runoff showing probable course of historic stream patterns
Link to the image on Proteus Gowanus Flickr
Further information about the above image
This is a test research map by Eymund Diegel combining hydrological runoff data from modern digital elevation models (2004 DEM and 2010 LIDAR topographic models) with historical military survey maps. (the 1915 Stevens edition of the 1782 British Headquarters Military Survey Map).
By combining these two data sets, and cross referencing them with modern sewer maps, valuable insights can be obtained to help solve road flooding and sewer backup problems. Old stream lines on this map coincide with many of the calls to the City's 311 call system for flooding and sewer backup complaints.
Follow up field research in March 2014 established that natural springs along Prospect Park West may currently be flowing into Park Slope's combined sewer pipe system.
As part of the 2013 Gowanus Canal Superfund Cleanup Plan, New York City is been ordered by the United States Environmental Protection Agency to spend 78 million dollars to find solutions to combined sewer overflows into the Gowanus Canal. Currently two sewer holding tanks have been proposed.
This ongoing research explores more sustainable alternatives and discussion about the currently proposed combined sewer tanks that would be built in the flood zone. One alternative is to better understand where water was historically stored in the upslope landscape - the watershed's ponds and wetlands. Many of these damp sites, because they were unsuitable for housing ended up as City properties: small parks and playgrounds, and later schools or public housing.
You can explore a dialogue here of converting some of those historical ponds / playgrounds back to their storm water management functions as rainwater holding tanks in this rough draft of a Gowanus Watershed Plan:
You can find a good discussion about how roads can be better designed to handle storm water here: http://www.gowanusyourfaceoff.com/2012/12/18/ted-talks-street-creeks/
You can find the larger 1782 map here: https://www.flickr.com/photos/51802375@N04/13024046625/