Mississippi River Basin Model, Scale model in Hinds County, United States.

The Mississippi River Basin Model is a 200-acre hydraulic model of the entire Mississippi River basin near Clinton, Mississippi. Built from individually cast 10 ft x 10 ft concrete panels, it reproduces tributaries, cliffs, lakes, flood plains, bridges and levees at a vertical scale of 1:100 and a horizontal scale of 1:2000. Metal plugs and folded metal mesh simulate riverbed materials and dense foliage.

Eugene Reybold of the Army Corps of Engineers proposed the basin-wide model in 1941, after earlier levees and local models proved insufficient following the 1927 flood. Construction began in January 1943 using German and Italian prisoners of war housed at Camp Clinton; the first 200, from Rommel's Afrika Korps, arrived that August. Sections operated from 1949, the whole was finished in 1966, and the last use came in 1973 at the Old River Control Structure.

Visitors reach the derelict model through Buddy Butts Park, entering from McRaven Road beside the soccer fields. Since 2000 it has appeared on the Mississippi Heritage Trust's 10 Most Endangered List, and urban explorers and photographers have documented the overgrown concrete panels and surviving walkways. In 2018 the American Society of Civil Engineers named it a National Historic Civil Engineering Landmark.

Access is via the park entrance on McRaven Road, with the model beside the soccer fields in Buddy Butts Park. The concrete panels, observation tower and walkways remain in place but are overgrown and partly defaced, so wear sturdy shoes and watch for collapsing grid sections.

Engineers designed the model with specific vertical and horizontal scale ratios—1:100 and 1:2000 respectively—to accurately simulate water movement across thousands of miles of waterways. This unusual combination of different scales was essential to achieving realistic water flow patterns.