Mammoth Spring is a large,
first magnitude karst spring
A karst spring or karstic spring is a Spring (hydrology), spring (exsurgence, outflow of groundwater) that is part of a karst hydrological system.
Description
Because of their often conical or inverted bowl shape, karst springs are also known i ...
that arises in the
Ozark Plateau
The Ozarks, also known as the Ozark Mountains, Ozark Highlands or Ozark Plateau, is a physiographic region in the U.S. states of Missouri, Arkansas, and Oklahoma, as well as a small area in the southeastern corner of Kansas. The Ozarks cov ...
within the state of
Arkansas
Arkansas ( ) is a landlocked state in the West South Central region of the Southern United States. It borders Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, Texas to the southwest, and Oklahoma ...
. It is the largest spring in Arkansas and the third-largest spring within the Ozark Plateau region behind
Big Spring and
Greer Spring. Mammoth Spring is the seventh-largest natural spring in the world.
The spring's outlet pool is contained entirely within
Mammoth Spring State Park. The park is located in the town of
Mammoth Spring, which lies in extreme north-central Arkansas. The outlet pool is adjacent to
US Highway 63, only 500 ft. south of the Missouri border, and it can be readily seen from the highway. The spring's large discharge volume rushes a few hundred feet down the outlet channel before merging with the
Warm Fork of the Spring River to form the
Spring River. The cold water that emerges from the spring creates excellent trout fishing conditions and ample flow for water sports on the Spring River. Mammoth Spring was declared a
National Natural Landmark
The National Natural Landmarks (NNL) Program recognizes and encourages the conservation of outstanding examples of the natural history of the United States. It is the only national natural areas program that identifies and recognizes the best e ...
by the
Department of the Interior
The United States Department of the Interior (DOI) is an executive department of the U.S. federal government responsible for the management and conservation of most federal lands and natural resources. It also administers programs relatin ...
in June 1972.
Description
Precipitation that falls in southern
Missouri
Missouri (''see #Etymology and pronunciation, pronunciation'') is a U.S. state, state in the Midwestern United States, Midwestern region of the United States. Ranking List of U.S. states and territories by area, 21st in land area, it border ...
seeps into the
water table
The water table is the upper surface of the phreatic zone or zone of saturation. The zone of saturation is where the pores and fractures of the ground are saturated with groundwater, which may be fresh, saline, or brackish, depending on the loc ...
and flows through a vast system of passages and cavities. These cavities form an underground river that ultimately emerges on the surface at the town of Mammoth Spring, Arkansas. The emerging water forms a 10-acre spring pool that drains over a high stone dam. The spring generates a harmonic mean flow of about 9 m³/s (322 cubic feet per second). The water emerges at a constant 14 °C (58 °F). The spring itself cannot be viewed at the Mammoth Spring site because its mouth is more than 21 m (70 ft) below the surface of the large spring pool.
Nine miles northwest of Mammoth Spring, visitors can see a portion of the underground river that feeds the spring at a collapsed
cave
Caves or caverns are natural voids under the Earth's Planetary surface, surface. Caves often form by the weathering of rock and often extend deep underground. Exogene caves are smaller openings that extend a relatively short distance undergrou ...
in
Grand Gulf State Park in Missouri. The remains of a portion of the cave are now a 40 m (130 ft) deep chasm with a natural bridge over it. Dye tests have proven that the water flowing through the 40 m (130 ft) chasm at Grand Gulf exits through the existing cave and emerges at Mammoth Spring.
Industrial use
The spring was used to power a gristmill from the times of the earliest European settlement. The Mammoth Spring Milling Company constructed a dam and a water-powered gristmill just downstream of the outlet of the spring lake. In 1925, the dam was purchased by the Arkansas-Missouri Power Company which constructed a
hydroelectric plant
Hydroelectricity, or hydroelectric power, is electricity generated from hydropower (water power). Hydropower supplies 15% of the world's electricity, almost 4,210 TWh in 2023, which is more than all other renewable sources combined and also mo ...
at the dam. This plant supplied power to the surrounding area until 1972.
Park
In 1957,
Mammoth Spring State Park was established. Surrounding land claims could not be acquired until 1972, however. Prior to 1972, the Mammoth Spring Cattle Sales Barn was co-owned and run by local entrepreneur Bert Kenneth Bishop and his associate, roughly on the site of where the Welcome Center now stands. Local farmers would routinely come to the site to sell livestock and other wares, such as Howard Green, who sold home-made walking sticks. Following this period in history, the State legislature voted to condemn the land and join the plot to the state park.
The original Frisco Depot was restored in 1971 and now functions as a repository for artifacts and memorabilia related to the railroad and the spring area. The State Park provides a visitor's center, picnic areas, walking trails, and tour access to the dam and hydro plant.
The
United States Fish and Wildlife Service
The United States Fish and Wildlife Service (USFWS or FWS) is a List of federal agencies in the United States, U.S. federal government agency within the United States Department of the Interior which oversees the management of fish, wildlife, ...
maintains a
fish hatchery
A fish hatchery is a place for artificial breeding, hatching, and rearing through the early life stages of animals—finfish and shellfish in particular.Crespi V., Coche A. (2008) Food and Agriculture Organization of the United Nations (FAO) Gloss ...
near the spring.
See also
*
List of Arkansas state parks
There are 52 state parks in the U.S. state of Arkansas, as of 2025. ''Note: this list of all 52 parks is the default reference for current individual Arkansas state parks.'' The state parks division of the Arkansas Department of Parks, Heritag ...
*
List of Arkansas rivers
This article is a list of rivers in the U.S. state of Arkansas.
By drainage basin
This list is arranged by drainage basin, with respective tributaries indented under each larger stream's name.
Red River
* Mississippi River
** Red River
*** ...
*
List of Missouri rivers
*
List of Ozark springs
References
External links
Mammoth Spring State Park
{{authority control
State parks of Arkansas
Protected areas of the U.S. Interior Highlands
Protected areas of Fulton County, Arkansas
Springs of Arkansas
National Natural Landmarks in Arkansas
Hydroelectric power plants in Arkansas
Buildings and structures in Fulton County, Arkansas
Bodies of water of Fulton County, Arkansas