Thornton Quarry is one of the largest aggregate

quarries A quarry is a type of open-pit mine in which dimension stone, rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some jurisdictions to manage their safet ...

in the world, located in

Thornton, Illinois Thornton is a village in Cook County, Illinois, United States, and a south suburb of Chicago. The population was 2,386 at the 2020 census. Thornton is home to the Thornton Quarry, one of the largest quarries in the world. Geography Thornton is ...

just south of

Chicago Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...

. The quarry is long, wide, and deep at its deepest point. Gallagher Asphalt Corporation has been operating on the grounds of the quarry since 1928. A dryland dike carries

Interstate 80 Interstate 80 (I-80) is an east–west transcontinental freeway that crosses the United States from San Francisco, California, to Teaneck, New Jersey, in the New York metropolitan area. The highway was designated in 1956 as one of the ori ...

Interstate 294 Interstate 294 (I-294) is a tolled auxiliary Interstate Highway in the northeastern part of the U.S. state of Illinois. Forming the southern portion of the Tri-State Tollway in Illinois, I-294 runs from South Holland at I-80/ I-94 and Illino ...

Tri-State Tollway The Tri-State Tollway is a controlled-access highway, controlled-access toll road in the northeastern part of the U.S. state of Illinois. Originally U.S. Route 41 Toll, it follows: *Interstate 94 in Illinois, Interstate 94 from I-41/US 41 in N ...

over the quarry. As part of the Chicago Deep Tunnel project, both Thornton Quarry and McCook Quarry will serve as reservoirs to reduce the backflow of stormwater and sewage from Chicago area rivers into Lake Michigan. Thornton Transitional Reservoir contributes a capacity to the system, and is expected to contribute when the system is expected to be completed in 2029. It is estimated that the reservoir will help protect 500,000 people who live in the surrounding 14 suburbs it serves, and will save the city around $40 million worth of damages each year. The quarry contains

Silurian The Silurian ( ) is a geologic period and system spanning 23.5 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the third and shortest period of t ...

reefs which formed when the

Michigan Basin The Michigan Basin is a geologic basin centered on the Lower Peninsula of the U.S. state of Michigan. The feature is represented by a nearly circular pattern of geologic sedimentary strata in the area with a nearly uniform structural dip towar ...

was covered in sea water more than 400 million years ago.

History

The first settlers came to Thornton, Illinois, in 1834. Gurdon Saltonstall Hubbard received of land from Watseka, his Potawatomi wife. In 1836 Hubbard opened the first quarry on Kinzie Street. The site was abandoned because the stone was too deep and of poor quality. Fred Gardner opened a quarry in 1846, and Stephen Crary opened one in 1850. In the early 1900s, Brownell Improvement Company purchased the entire area. Colonel Hodgkins bought the property in 1920. The quarry north of Ridge Road was opened in 1924, and a tunnel connecting the north and south quarries was developed in 1926. Colonel Hodgkins died in 1929, and Brownell repurchased the quarry in 1933. Then in 1938, Material Service Corporation purchased the property and has owned it ever since.

Contract with MWRD

The

Metropolitan Water Reclamation District of Greater Chicago The Metropolitan Water Reclamation District of Greater Chicago (MWRD), originally known as the Sanitary District of Chicago, is a special-purpose district chartered to operate in Cook County, Illinois, since 1889. Although its name may imply oth ...

(MWRD) contracted to use the quarry for stormwater overflow in 1998 as part of the Deep Tunnel or Tunnel and Reservoir Plan (TARP) for the metropolitan area. The Thornton Quarry supplies 7.9 billion gal US of stormwater storage, allowing the water to be treated before release into the waterways.

References

External links

* *
Thornton Quarry history
*Army Corps of Engineers

Quarries in the United States Geology of Illinois Interstate 80 Interstate 294 Buildings and structures in Cook County, Illinois Geography of Cook County, Illinois Metropolitan Water Reclamation District of Greater Chicago {{mining-stub