Old River Control Structure of 1973 almost caused the control structure to fail. Integrity of the Old River Control Structure, the nearby Morganza Spillway, and other levees in the area is essential to prevent such a diversion. Jeff Masters of "Weather Underground" noted that failure of that complex "would be a serious blow to the U.S. economy." The present Old River Control Structure was completed in 1964 and expanded in 1990. The first two floodgates are the Low Sill Control Structure, which regulates routine flow in the waterway, and the Overbank Control Structure, in use only when the Mississippi exceeds its banks. A navigation
U.S. Route 190 the Beauregard Parish Jail, Beauregard Parish Courthouse, and the DeRidder Commercial Historic District. US 190 runs concurrently with US 171 to Ragley, where US 190 parts with US 171 heading east. From Ragley, the two-lane highway heads nearly due east almost parallel to I-10 until Opelousas. US 190 crosses the northern reach of the Atchafalaya Basin near the Morganza Spillway en route to Baton Rouge. From Baton Rouge, US 190 passes, in places divided, through Denham Springs, Albany, Hammond, Robert, Goodbee, Covington, Mandeville, before reaching the eastern terminus at Slidell. The stretch between I-12 south of Covington and the intersection