California Numbered Exit Uniform System

The California Numbered Exit Uniform System (Cal-NExUS) is the California Department of Transportation's (Caltrans) program for numbering the exits of California's freeways. The program began in February 2002. [Brown, Patricia Leigh. "Counting the way to San Jose." "New York Times", 10 February 2002, sec. WK, p. 2.] The system assigns exit numbers south-to-north and west-to-east on a mile-based system, where each exit is numbered based on how far it is from the highway's southern or western terminus. This system is used in other states such as Oregon and Washington. The Federal Highway Administration (FHWA) generally requires mile-based exit numbers on the Interstate Highway System; the FHWA established that requirement in 1970. [http://www.cahighways.org/num-postmiles.html California Highways: Numbering Conventions - Postmiles] . Accessed: 17 July 2008.] . The Manual of Uniform Traffic Control Devices (MUTCD) encouraged use of mileposts and exit numbering by 1961. The MUTCD mandated mile-based exit numbering in 1971. [http://www.cahighways.org/num-postmiles.html California Highways: Numbering Conventions - Postmiles] . Accessed: 17 July 2008.] By then, California had designed and built most of its Interstate Freeways. The FHWA granted California an exception due to the cost of installing and maintaining additional signage. Contrast this with a sequential numbering system, which numbers exits in sequential order, regardless of distance between exits, which is used in some states.

The program is not well-funded, so exits are only being signed with numbers when signs need to be replaced. As the efficiency of an exit numbering system for navigational purposes depends on all exits being consistently numbered, the usefulness of the system while only some exits are numbered is limited. Originally the initial completion date for this project was set as November 2004. The current deadline for completion of the project is November 2008.

In most cases, the exit numbers (and letters) on signs posted in advance of the offramps are not found on "exit tabs", but instead on the actual large sign (usually in the upper right-hand corner), separated from the rest of the sign by an angled white line. California's way of signing exit numbers is unique in the U.S.

As of 2004, of the 5,936 exits in California, 359 are in full compliance (6.0%), 786 are in minimum compliance (13.2%), and 1,115 are in partial compliance (18.8%). There are 2,498 numbered exit signs. Compliance varies widely from district to district. For example, in District 3, in north-central California in the area around Sacramento, 34% of exits are in full compliance and 51% are in partial compliance, whereas in District 7, Los Angeles and Ventura counties, no exits are in full compliance and 4.4% are in partial compliance.

As of May 1, 2008, there are 5,985 exits in the Cal-NExUS system; 1,165 exits are in full compliance (19.5%), 1,913 exits are in minimum compliance (32.0%), and 3,418 exits are in partial compliance (57.1%). The other 2,567 exits are non-compliant. [ [http://www.cahighways.org/num-exitnum.html California Highways: Numbering Conventions Exit Numbers] . Accessed: 17 July 2008.] Compliance varies widely from district to district.

References

External links

* [http://www.cahighways.org/num-exitnum.html CAHighways.org report on Cal-NExUS]
* [http://www.dot.ca.gov/hq/traffops/signtech/calnexus/ Caltrans' official Cal-NExUS site]
* [http://www.cahighways.org/images/CalNexus-Compliance-Trends-2007.pdf CalNExUS Compliance Trends]