The claim that the Lake of the Ozarks (LOZ) has more coastline than California is a popular piece of regional folklore. This claim is rooted in a numerical truth, but it relies on a fundamental misunderstanding of the terms used for measurement. The comparison pits the highly detailed, man-made perimeter of an inland reservoir against the standardized, natural boundary of an oceanic state.
The Direct Answer: Comparing the Lengths
The claim that the Lake of the Ozarks’ perimeter is longer than California’s coastline is numerically true when relying on the most commonly cited figures. The Lake of the Ozarks, a man-made reservoir in central Missouri, is consistently measured by tourism and local sources as having approximately 1,150 miles of shoreline. This measurement includes the perimeter of the main channel, the Osage Arm, and the numerous tributary arms and coves created by the impoundment of the Osage River. In contrast, the widely cited figure for California’s mainland coastline is 840 miles. Based purely on these figures, the Missouri reservoir’s perimeter is longer.
The Crucial Distinction: Shoreline vs. Coastline
The core issue with the comparison is the difference between a “shoreline” and a “coastline.” Lake of the Ozarks is a man-made reservoir, created by the construction of the Bagnell Dam across the Osage River between 1929 and 1931. The lake’s perimeter is a shoreline, an inland boundary formed by the flooding of a deeply dissected river valley. This process resulted in a highly serpentine shape with countless small coves and indentations, all measured to achieve the maximal length. California’s boundary, however, is a coastline—the dynamic boundary where land meets the ocean or sea, measured using standardized methodologies.
How Measurement Affects the Outcome
The length of any shoreline or coastline is not a fixed, well-defined measure, a concept known as the Coastline Paradox. The measured length depends entirely on the unit of measurement, or the virtual “ruler” used. The finer the detail measured—including every tiny cove, inlet, and protrusion—the longer the resulting length becomes. When the National Oceanic and Atmospheric Administration (NOAA) employs a more detailed, standardized tidal methodology that includes offshore islands, sounds, bays, and rivers to the head of tidewater, California’s total shoreline mileage balloons to 3,427 miles. If California’s coast were measured with the same ultra-detailed methodology used for the Lake of the Ozarks, its length would far exceed the reservoir’s perimeter.