8 replies to this topic

[benbakelaar]

Does someone know anything more about the NYCMap situation? I have found these two references:

2001 ESRI conference - http://gis.esri.com/...pap949/p949.htm

2005 City Council meeting - http://webdocs.nycco...FTOKEN=43169673

I am aware of the website: http://gis.nyc.gov/doitt/mp/Portal.do

[ELeFevre]

Does someone know anything more about the NYCMap situation? I have found these two references:

Ben,
I'm not sure about the "situation" of the base map, but here several data links you might be interested in.

Landmarks Preservation Commission

DOITT (Department of Information Tech) - GIS data

Link page for NYC GIS data

NYS GIS Clearinghouse

[benbakelaar]

Ben,
I'm not sure about the "situation" of the base map, but here several data links you might be interested in.

<{POST_SNAPBACK}>

Thanks for the links Erin, I've been to most of them... the situation is that DOITT has not released the GIS layers to the public, which are more accurate and up-to-date than anything provided on the other sites.

[ELeFevre]

... the situation is that DOITT has not released the GIS layers to the public, which are more accurate and up-to-date than anything provided on the other sites.

From the little bit of reading I've done about the base-map, I've gotten the impression that the hesitation to release data is related to security issues (9-11). Does this sound about right?

[benbakelaar]

Exactly. The city council meeting minutes address this, and advise the DOITT to release at least the "non-sensitive" layers... but a year later there seems to be no progress.

[benbakelaar]

To provide a little more information, NYC hired Rand Corporation to do a security assesment of this map. Their framework asked 6 questions:

1. Is NYCMap information useful for target selection or location purposes?
2. Is NYCMap information useful for attack planning purposes?
3. Is NYCMap information readily available from other geospatial information sources?
4. Is NYCMap information available from direct observation or other nongeospatial information types?
5. What are the expected societal costs of restricting public access to NYCMap information?
6. What are the expected security benefits of restricting public access to NYCMap information?

You can find answers to all those questions in the 2005 city council meeting minutes... but here is the answer to #6 given in the minutes.

Security Benefit: Combinations of GIS Information May Be Risky

No one really knows what the risk is of a terrorist combining many layers of seemingly non-sensitive GIS information together that alone would pose no security threat, but combined, could pose one.

[danielle]

We deal with these data sharing issues all the time. It depends in part on the political climate and who is in charge of a department. Before security issues became so prominent, there were several other excuses not to share data.

The NYCMap data looks nice, but it is sparsely attributed. The building polygons don't have any meaningful ID numbers. You can view some detailed interactive maps on the DOITT website, but if you get the licensed data files, those attributes are not included. You have to rebuild the complete dataset yourself.

We have gone through the task of assigning taxlot ID numbers to each building so we can make thematic maps for certain areas. This takes a bit of time, since the taxlot boundaries don't line up with nicely with the buildings. We're happy to do it if a client has the budget, but honestly I would rather be designing maps rather than cleaning up data. One of these days we will get a building layer with unique BIN numbers that can be linked to all the other databases....maybe someday before I retire.

If there is a particular type of map you want to create, send me a PM and we can discuss the specifics of what you would need. We do this all the time for clients and other consultants. For large joint venture projects, we are often the group in charge of the data.

(BTW, my former boss is a big advocate of data sharing in NYC. Those images on the City Council brief are something I made for our website.)

-Danielle

[benbakelaar]

What I was envisioning the NYCMap providing me, based on what I read, was an accurate basemap containing accurate coastlines, borough boundaries, water bodies including rivers/ponds, designated parks, industrial areas (i.e. 0 population census tracts), roads, and lots. I've put together most of these pieces, but in many cases there are overlap errors and data join issues.

[danielle]

What NYCMap contains, as a dataset, is primarily information extracted from aerial photos. They have added street centerlines with names, but they are not the same as the geocodable LION files. You can read more about the dataset in the article my colleagues wrote in the 2001 ESRI paper, or at http://www.comcarto.com/basemaps.html.

Basic census data is available from several sources, including ESRI. Tracts with 0 population are usually parks, cemeteries or airports. Not many industrial parks, but maybe the Navy Yard and some piers will show up that way.

There's not a good single source for parks, so we've made our own layer.

The only way to get taxlots is to pay for the license.

So yes, it is a pain to get everything together. That is why we started our consulting company. For smaller projects, it is often cheaper to contract out the work to us, rather than spending the person-hours to collect all the required data.

We get calls all the time from people trying to navigate their way through the data. It is getting easier, but slowly.

-Danielle