Max,
Orangeline BRT is 18 miles, no significant grades, converted to BRT from the former Southern Pacific Chatsworth branch line from Burbank Jct, to Chatsworth. BRT runs from terminus of the Redline subway in North Hollywood, to Chatsworth. Here are the basics:
Orange Line Wiki Basics
The Valley opposed "evil" rail and opposed LRT, which resulted in the BRT options being chosen. Now, some the very same politicians, some of whom opposed rail want to spend over 3 billion to convert it to LRT.