Caldwell Nature Preserve — Public Lands Institute

Ordovician450 Mya

~450 Mya Late Ordovician Kope Formation, 75 percent gray to bluish gray shale interbedded with 25 percent thin limestone, 200 to 260 feet thick; the blue-gray clay shale is exposed directly in the preserve's creek beds where the ravines cut east toward Mill Creek.

Epoch

Late Ordovician (Cincinnatian Series, Edenian)

Native lands Glossary →

Shawnee (Shawanwaki) · Myaamia (Miami); the Mill Creek valley a north-south travel corridor, with an Indigenous trail running past the third Mill Creek crossing at present Carthage westward to the Great Miami and on to North Bend, a route later taken over directly by settler roads; Jacob White's Station, a blockhouse and six cabins built at that crossing in 1790, and Caldwell's adjacent blockhouse and mill fortified the corridor during the Northwest Indian War; Shawnee and Miami ceded southern Ohio via the Treaty of Greene Ville, August 3 1795, following the Battle of Fallen Timbers in 1794.

Displacement & Tenure

Cession 11: Treaty of Greene Ville (1795). The tract sits inside the Symmes (Miami) Purchase, the patent for 248,250 acres between the Great and Little Miami Rivers signed by George Washington on September 13 1794 and extending roughly 24 miles north of the Ohio; settlement at the Mill Creek crossing here preceded the cession by five years. J. Nelson Caldwell conveyed 89.3 acres of the family holding to the Cincinnati Board of Park Commissioners in 1915, though Cincinnati Parks dates the park itself to the family heirs' gift of 1914; the preserve has since grown to roughly 123 acres.

Shadow History

The preserve's ravines drain into Mill Creek, which American Rivers named the most endangered urban river in the country in 1996, citing three Superfund sites on its banks, 31 other hazardous waste sites, and 158 combined and sanitary sewer overflow outfalls; in 1992 the Ohio Department of Health found Mill Creek fish unsafe to eat and Ohio EPA advised against body contact with the water. Combined sewer outfalls immediately below the preserve still release untreated sewage during heavy rain, and the greenway and creek bank stabilization work running from the Caldwell playground to West Seymour Avenue was built by the Metropolitan Sewer District under the federal consent decree Cincinnati and Hamilton County entered in 2002, which requires capture, treatment, or removal of 85 percent of roughly 14 billion gallons of annual overflow. Cincinnati Parks records the site as the location of the park system's first nursery and as the home of a formerly enslaved person, though no name, dates, or further account of that residence appears in accessible public records.

Ecology

Mature mixed mesophytic forest, one of three surviving old growth stands inside Cincinnati city limits, with individual trees over 200 years old; American beech, red and white oak, sugar maple, shagbark hickory, black cherry, tulip poplar, and pawpaw on the ravine slopes; screech owl, red fox, and eastern box turtle resident, with continuous staff removal of bush honeysuckle and garlic mustard.

Hydrology

Unnamed spring-fed ravine creeks drop roughly 130 feet from the ridge at about 650 feet to Mill Creek at about 520 feet, cutting steep Kope Formation ravines with blue-gray clay shale exposed in the beds; Mill Creek drains 166 square miles of Hamilton County to the Ohio River; combined sewer outfalls discharge to the creek below the preserve in wet weather.

Acreage

123

GPS

39.2016° N, 84.4924° W

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