Mapping Speed Limit Data?

[MichaelRyan1]

I am a college student in New York State doing an internship with the local town planning department, and one of my projects is to find all the speed limits of every road in the town and make a map including this info. They want me to use a GPS device to literally drive on every road and locate every change in speed limit that way, but would there be any simpler way to find speed limit data? Are there any online databases which include this information? Any advice is greatly appreciated!

[AndrewIrwin]

Some ideas: 1) Start by checking your town's ordinances, as speed limits may be codified for certain areas (e.g., all residential areas 20 MPH), although any such ordinances may not be accurate or up-to-date. 2) Check with the town's public works department or road department; there may be records of sign placement or speed zones. 3) If your town is covered by Google Street View, you can digitally "drive" the streets looking for speed limit signs.  Avoid big "jumps" as it is easy to miss signage in Street View, and do check streets in both directions, whether in Street View or in the field, as speed limits are not necessarily the same in both directions for any given segment.  4) If all else fails, hit the road with that GPS unit; ultimately, being there will produce the highest quality data.  Aloha, Andrew Irwin, Maui County Geographic Analysis & Cartographic Services (GIS), Wailuku Maui.

[DerekFord]

Hi Andrew, I'm working on a network analysis for Maui right now, do you know if roads with speed limits data is available?

[KevinSharpe]

Do like Skylark says and start with the ordinances.
We did a similar project, and I used a combination of the ordinances, google earth's street view, and trips to the field.
If an area has reamined static for several years, and there is google earth streetview coverage, this is great, as you can verify limits, somewhat, since the speed limit signs aren't posted right at the limits, and if there have been changes, as was the case with us on a couple of the roads, a run out with a handheld was all that was needed for the few locations that required a visit.

[TedCarrasco]

Check with your school district and see if any of their buses have GPS and see if they are capturing speeds.  Also some utilities and government vehicles have GPS.

[JoshuaDamron]

Being that this post was started a few months ago this might not be helpful but the cities Public Works/Road Maintenance Department should have speed survey data on hand; if not they likely rate the condition of their roads every so many years for maintenance purposes, vehicle speed is an important aspect of rating a roads condition.  You might try asking a inter-department favor for the documentation you are looking for.

[islamisohbet]

You can probably get info from the governmental departments, it is not so easy to go around all roads, and maybe there is a traffic control center, then you can get help.

[StephanieSnider]

You need HPMS speed limit data.  Check out the New York Dept of Transportation GIS site.

NYS GIS Clearinghouse - NYS GIS Program Office - NYS Streets 

It looks like the NYS Streets dataset is what you need.