A Missouri Pacific Railroad Junction
By the late 1950s or early 1960s, Railroad Commission of Texas (RCT) policy had evolved to the point where numbered interlocker authorizations for "single railroad" junctions were only required when upgrading to an automatic interlocker. Such was the case for Tower 211, assigned during an automatic interlocker upgrade in Corpus Christi where two Missouri Pacific (MP) lines crossed. Part of the junction had existed for approximately 30 years; a spur to the south from MP's main line was built between 1927 and 1931 as indicated by Sanborn Fire Insurance maps of that era. An extension to the north was built in 1959 to serve the Port of Corpus Christi via the Tule Lake Lift Bridge, and it was perhaps this construction that motivated the installation of an automatic interlocker in 1960. The Port's own published history explains it best...
No history of the Port would be complete without some detail of the Bascule Bridge and the removal of the "Bascule Bridge Bottleneck". When the Port was constructed in 1925, there was a small bayou at the entrance which was crossed by a two-lane highway bridge and the railroad bridge of the S.A & AP Railway (Southern Pacific). To permit the passage of large ships, a Bascule bridge was erected which had about 100 feet of horizontal width and 14 feet of vertical height above the water. This was adequate to handle the ships which were in use at that time. Fenders and timbers to protect the structures on the inside reduced it to about 98 feet in horizontal width. Of course, the bridge was "OPENED" when a ship approached. By the 1950's the volume of both ship and vehicular traffic had increased to such extent that there was an urgent need to break the "Bascule Bridge Bottleneck". Southern Pacific entered Corpus Christi from Portland via a trestle across the bay and via the Bascule bridge to/from its yard on the south side of the inner harbor channel. Incidental to removing the Bascule bridge two thing occurred: first the Tule Lake lift bridge was constructed to facilitate rail and highway access to/from the north side; second, the Savage Lane line was built to connect the Tex Mex yard on Agnes street to the north side via the Lift Bridge. Southern Pacific continued to operate to/from Portland and transited along the north side of the inner harbor channel to/from the Tex Mex yard. ... It wasn't until sometime in the 1970s that SP ceased accessing Corpus Christi from Portland. SP then worked out a deal for rights on Missouri Pacific to access Corpus Christi.
The "Savage Lane line" reference appears to be the southerly spur off of the MP line. But...this spur clearly existed on the 1931 Sanborn Fire Insurance map of Corpus Christi, so the reference to it being constructed in the 1950s is inexplicable. Perhaps it had been abandoned and was rebuilt?
All of the lines involved remain in use by successor Union Pacific (UP). The spur to the south connects with the Texas Mexican Railway, owned by Kansas City Southern (KCS). KCS has trackage rights to use the spur and has traditionally used it to access the Port. In 2008, the Tule Lake Lift Bridge was demolished, eliminating this route for KCS to the Port. KCS objected to the demolition and instigated litigation against the Port of Corpus Christi for damages resulting from the higher expenses it incurs using the alternate route to the port via tracks off the UP main line further inland.