The Mississippi River Is Not What You Think

The Mississippi River is trying to change course. A set of gates in central Louisiana is what keeps it from taking a shorter, steeper road to the Gulf, and in 1973, by the Corps' own account, only emergency repairs kept that structure from collapsing. This is the story of the Old River Control Complex, and of the 70/30 rule written in 1954 that still decides where the water goes. Chapters 0:00 The river that wants out 1:12 April 1973 2:35 142 miles to the Gulf 4:46 How Old River was made 6:12 The 1951 warning 7:41 Building the gates 9:30 Morganza opens 10:31 The peak 11:55 22 feet: the new limit 14:26 What 70/30 really means 16:47 Still being tested 18:46 What's at stake Sources • US Army Corps of Engineers, New Orleans District: Old River Control brochure (2009), Morganza Floodway overview, news releases 15-017 (2015) and 23-029 (2023) • Mississippi River Commission / USACE: The Atchafalaya River Study (1951) • 33 U.S.C. §702c note: Flood Control Act of 1954, §203 • ERDC: Old River Control Low Sill Structure, Monitoring and Performance (MP-25-3, 2025); scour survey story (Feb 2026); MRG&P Tech Note 5 (2018) • USGS Professional Paper 937: The 1973 Mississippi River Basin Flood (1975); USGS NWIS gauge 07381490 (Simmesport); USGS Fact Sheet 021-02 • NWS New Orleans/Baton Rouge: lower Mississippi flood history • EPA: Mississippi/Atchafalaya River Basin • USDA AMS: A Reliable Waterway System is Important to Agriculture (2025) • Ford & Nyman (2011), Hydrobiologia 658 Images: US federal government works (USACE, USGS, NASA/Landsat, US Coast Guard via DVIDS) and royalty-free stock footage. Maps from USGS 3DEP elevation, USGS NHD and US Census data. Narration is AI-voiced. Script, research and analysis are original.