@tferk wrote:

Charlie, I have studied many Circular 61 freight schedule pages that indicated southbound Mexico traffic was set out at San Antonio “to be manifested”. Several different blocks from several different trains, set out, then to be handled later on trains to Laredo (DM, DMZ, etc.) Was this practice a response to the congestion in Laredo from too many cars waiting for release on too few tracks?

Yes, as U.S. businesses moved south and the Mexican economy grew Laredo remained Mopac’s largest interchange with the NdeM. Initially southbound autoparts were pre-manifested due to the JIT nature of the auto business. Grain trains were pre-manifested due to not wanting to hold an entire grain train in Laredo but I remember some grain stopping due to the Mexican grain inspectors wanting to samples. Gardendale was a favorite spot to hold cars going to Laredo and Harlingen, Kingsville and Bloomington to places were Brownsville traffic was held. MP tried to use Brownsville as the favored interchange for grain but it didn’t always more through there due to the Mexican destinations. MP initiated tariffs and computer steps in the early 1980s to pre-manifest all loads as we’d receive the waybill from the origin railroad as soon as they received the bill of lading from the shipper. Notice would be given to the U.S. broker as soon as we received the waybill to begin their clearance process with U.S.Customs (USC) and Mexican customs. This helped to streamline much of the switching in all the border locations. On the northbound moves out of Mexico USC would do random inspections so cars would be set out where it could be unloaded, inspected, and reloaded. I remember one car coming up from Mexico with the ends being packed with drugs and the car had been given false wood ends on the interior to hide the bags. USC was able to stop this ’empty’ from reaching its destination.

Brownsville and Laredo yards were both in downtown areas and close to the Rio Grande river. There were at least two street crossings cutting through the yard which added to the switching problems. Some traffic to (both northbound and southbound) was destined to Laredo or Brownsville and unloaded in a warehouse and trucked to destination.

I mentioned the bridges which besides the Mopac using the SP also used in Brownsville and the Tex-Mex in Laredo. I remember too the station in Laredo was still painted yellow and brown well into the 1980’s and probably still is.