Wikipedia:WikiProject U.S. Roads/Lengths
From Wikipedia, the free encyclopedia
This page is for determining the precise length of a numbered route. The majority of information is to at least two decimal places, so that should probably be a good standard.
ArcExplorer is a good free GIS viewer for the states that use GIS data.
"Show your work" on the talk page of the article if it is complicated - for instance Talk:U.S. Route 30. Always cite the source with a footnote in the article.
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[edit] Interstates
The FHWA Route Log and Finder List includes mileages by state. Be careful on routes with concurrencies - the numbers after taking into account the concurrency may not be precise. If possible use the information from one of the states.
[edit] California
The Caltrans bridge log includes milepost information. Watch for milepost equations - points where the mileposts jump due to realignments.
[edit] Florida
Florida has GIS data. The pavement management reports might also help.
[edit] Idaho
The milepost log includes milepost information. Watch for milepost equations - points where the mileposts jump due to realignments.
[edit] Illinois
Illinois has GIS data, including begin and end milepost fields for each segment. If desired, use the unique values option to show the route as a specific color and a wider line. Be careful at concurrencies and other places where the sequence might change. They have a PDF listing Interstates only - it probably agrees with the FHWA data but I haven't checked.
See Wikipedia:WikiProject U.S. Roads/Lengths/Illinois for a working list of counties and U.S. and state route names and distances.
[edit] Iowa
Iowa has GIS data, but it is a bit screwy. Download ROAD_INFO, DIRECT_LANE and COUNTY_BORDERS_SO. If desired, use the unique values option to show the route as a specific color and a wider line. Find the last segment in each county and find the BEGINLRD value in ROAD_INFO and the LANELENG value in DIRECT_LANE, and add them. Be careful at concurrencies - if the route you are following is not the one given, you'll have to do more calculations.
[edit] Massachusetts
Quoted from SPUI's comments on my talk page:
It's a bit complicated. (This is assuming you have Microsoft Access; it may work slightly differently in other programs.) Download the Road Inventory Geodatabase and open it. Make a new query with the following fields:
- ROUTENUMBER ascending, criteria >="1" (to eliminate unnumbered roads)
- ROUTEDIRECTION
- ROUTEFROM ascending
- ROUTETO
- Other possibly useful fields are ROUTESYSTEM, CITY, STREETNAME, FROMSTREETNAME and TOSTREETNAME. Note that the from and to streets are not for the section that is numbered, but for the whole street, so make sure to check against mileage if you have issues with finding the exact end.
Once the query loads, scroll down to the route you want, and find the last entry in the northbound or eastbound (increasing) direction. That will give you the mileage. (Unless the route ends concurrent with another - I'm not sure if any do that, though some do begin concurrent, which isn't a problem.)
Tckma 20:03, 31 July 2006 (UTC)
[edit] Maryland
The highway location reference includes milepost information.
[edit] Nevada
Nevada includes the total length of their routes at State Maintained Highways, Descriptions, Index & Maps and NHS, as well as lengths by county (and Carson City).
[edit] New Jersey
New Jersey is by far the easiest I've found - simply open their straight line diagrams and go to the appropriate route, making sure to take into account concurrencies at the end of the route.
[edit] New York
New York provides mileages for every state route, touring and reference, in their annual Traffic Volume Report. The 2005 edition can be found here. The traffic volume appendix PDFs at the bottom contains the mileage.
[edit] Ohio
Ohio has straight line diagrams cut by county. Watch for milepost equations - points where the mileposts jump due to realignments.
[edit] Oregon
Oregon is the most complicated I've found. Open their TransGIS application and use the rectangle selector (once zoomed) to get the to and from mileages at transition points. Make sure to get the right highway numbers using the routes to highway cross reference. Also be careful of milepost equations - points where the mileposts jump due to realignments.
[edit] Texas
The TxDOT Highway Designation Files are probably your best source for Texas road-length information. At the top of the page for a given road is its' certified mileage, and an as-of date.
[edit] Wyoming
The reference marker book includes milepost information. Be sure to use the right column.
