Functional Classification: On vs Off System

It can be confusing trying to figure out what type of road is classified as an “on” system road versus an “off” system road. And what’s the difference between the NHS and the Federal-Aid System?

I’ve finally found the answers, not to mention a few minor torturing tactics that I developed along the way to pry this information out of my colleagues. But that’s another blog entry for another day 🙂 I hope you find this information helpful.

on vs off system

 

Streets and highways are grouped into classes based on the service they provide. The California Road System (CRS maps) display functional classification which is used in determining funding eligibility, as well as applicable design standards.

Additionally, here is a breakdown on Functional Classification (FC) by numerical value. They are color coded as displayed on the CRS maps.

A breakdown of non-State Highway NHS can be found here or at the Caltrans NHS website.

The NHS includes the following:

  • The Interstate System.
  • Principal arterials (including those not previously designated as part of the NHS) and border crossings on those routes.
  • Intermodal connectors — highways that provide motor vehicle access between the NHS and major intermodal transportation facilities
  • STRAHNET (Strategic Highway Network) — the network of highways important to U.S. strategic defense
  • STRAHNET connectors to major military installations.

 

Below is an example of a CRS map.

crs maps example

For more information regarding Functional Classification, NHS or the Federal Aid System, please visit: http://dot.ca.gov/hq/tsip/hseb/index.html

 

 

Google Earth being discontinued December 12, 2015

The map display in Caltrans Earth uses the Google Earth Application Program Interface (API) and Plug-In software. Google announced they will be retiring their API and Plug-In software on December 12, 2015. We were notified by Google that these components were developed on an older technology that they consider a security risk. There are no announcements from Google … Read more Google Earth being discontinued December 12, 2015