For the latest and most accurate border crossing information we know of, try the BorderTraffic.com's Border Wait App.
*If before getting to Calle Segunda this way is blocked off by authorities, they usually direct
traffic to take a right at the second Alto. This means the traffic will flow parallel to
Calle Segunda/the border line. At the first opportunity, take a left heading towards Calle
Segunda, then a left onto Calle Segunda.