The $12.6 billion number was stated by government officials and is cited in the Dallas News article[0] linked on that page. "County Commissioner Duncan Webb to

The $12.6 billion number was stated by government officials and is cited in the Dallas News article[0] linked on that page. "County Commissioner Duncan Webb told business leaders at a forum Wednesday that the county will need $13 billion for roads over the next three or four decades. Later Wednesday, former Commissioner Mark Reid, during a presentation to the Frisco Tea Party, said the figure is $12.6 billion." [0] https://www.dallasnews.com/news/collin-county/2018/09/13/transportation-bonds-small-bite-collin-countys-13-billion-future-highway-needs-officials-say https://www.dallasnews.com/news/collin-county/2018/09/13/tra...