"Salt water" is a term reserved for the Gulf of Mexico or man-eating crocodiles. But it's a descriptor that characterizes the Red River of the South, too; due to its origins in the gypsum canyons in the farthest reaches of the Great Plains, the river is not just red; it's full of brine.
No big deal, right? Might as well make use of it, like the Caddos did for hundreds of years when they retrieved the salt from marshes around the Great Bend region and traded it for lots of nice things. But the Caddos didn't get their drinking water from the Red River, and modern folks do. Because the high salinity of the river is dangerous for human consumption, the people in charge -- water boards, authorities, politicians, and the Army Corps of Engineers -- have had to finagle how to make the Red River potable. It's a constant battle that is evidenced in two particular places along the river: Estelline (Hall County, Texas) and Gainesville (Cooke County, Oklahoma).
Just outside of Estelline is a spring that arises in the Prairie Dog Town Fork's flood plain, a remnant from when Texas was a vast, shallow sea. This natural water hole was home to very specific animals that flourished in the high salt content of the waters, and all was well until the 1950s, when the spring became overly ambitious. The Army Corps of Engineers measured that the Estelline Spring released 300 tons of salt daily into the Red River: that's a bit too salty, considering that the water was supposed to be used for human consumption. To figure out why the spring had suddenly become so deadly, divers explored its depths in 1961 and learned that it appeared to be bottomless; was crystal clear and elongated; and that due to some geological event, a narrow "throat" had opened into the spring that allowed even more salt from the surrounding rock layers to inundate the water and spew it into the Red River. This new development may have been the result of oil drilling attempts. Downstream was Lake Texoma, which supplied drinking water to the people of southern Oklahoma and northern Texas, and all this salt released near Estelline would destroy Denison Dam's mechanisms and make the water unusable. This was a problem that had already reared its head mid-way between Estelline and Denison at Gainesville.
The major drought of the 1950s threatened to destroy the post-war prosperity in the Southwest, as water levels reached historic lows.* The city of Dallas was particularly worried about its dwindling water supply. In 1952, an idea was hatched by the city to pump water from the Red River into Pecan Creek in Cooke County, then into the Elm Fork of the Trinity River, which would add volume to Lake Dallas in Denton County, which was being expanded into Lewisville Lake. Great idea, right? What could go wrong? Well... lots. The salt being dumped into the river from the Estelline Spring threatened the state-of-the-art pumping station, which was built in 1954 (remnants of the station can still be seen on the southern side of the river near the Interstate 35 bridge). And, according to a report, the water captured from the Red River caused "the chloride content of [Dallas] city water [to rise] as high as 1,220 ppm (parts per million)" whereas the US Public Health Service recommends, at most, 250 ppm.
The culprits for all this saltiness was the Estelline Spring. In 1960, the Red River Valley Authority for North Texas and Southern Oklahoma (there was another authority for Arkansas and Louisiana) was formed to address the salt problem, among other projects, and it concluded that pollution was to blame. After conducting studies and surveys, the U.S. Army Corps of Engineers built a dyke around the spring in 1964, and drilled several "release holes" to dilute the natural waters (and killed off the native fauna, which had survived in this pocket of ocean water for millions of years). The pumping station at the Red River near Gainesville had already closed, however, mainly due to the sudden return of torrential rains in the late 1950s.
Today, Estelline Spring continues to be monitored by the Corps and has been caged off inside a privately owned ranch.
Read up more on the history of salt in Texas here!
*The drought's effect on river bottoms also revealed lots of archeological sites, but that's a topic for another post.
