ISAS reconstructs the Indian Springs Mound, Kennekuk Cove County Park, Vermilion County, Illinois

Approximately 1000 years ago, a Native American group constructed an earthen mound on the bluff edge overlooking the Middle Fork of the Vermilion River northwest of Danville in Vermilion County, Illinois. This mound, referred to as the Indian Springs Mound (11V82), is part of what is defined archaeologically as the Collins Archaeological Complex, or more simply as the Collins site, an extensive archaeological site comprised of a large village area and six additional earthen mounds.

Indian Springs Mound before reconstructionMulti-year, extensive excavations were undertaken at the site by the University of Illinois in the 1970s, prompted by a proposed reservoir on the Middle Fork that threatened to inundate most of the site. The U of I excavations indicated that the main occupation of the site occurred during the latter portions of the Late Woodland period in the eleventh century A. D. Notably, there is clear evidence that Collins site inhabitants at this time were in contact with and being influenced to some degree by the Cahokia site in southwestern Illinois. This contact was occurring early in Cahokia’s history when it was quickly developing into the largest and preeminent population/mound/religious/political center site north of Mexico and whose influences extended throughout much of the Midwest and Southeast.

The University of Illinois excavated portions of the Indian Springs Mound in 1971-1972 within an overall site investigation project that spanned 1970 to 1977. The mound was essentially intact prior to the initiation of these investigations, although some relic hunter disturbances were present.  The mound had an overall oval plan shape and a height of seven feet, the tallest mound in the complex. The excavations initially proceeded with narrow trenches in several areas but were expanded and became focused across a broad area in the eastern portion of the mound that exposed a burned, oval structure constructed out of red cedar and containing the remains of 5 individuals.  Upon completion of the mound excavations, plastic was laid over the extent of the excavation areas followed by a small amount of soil but unfortunately the trench areas and the broader area of excavation were never backfilled by the U of I archaeologists. As things developed, the proposed reservoir project was cancelled and the Collins site property became part of Kennekuk Cove County Park, administered by the Vermilion County Conservation District (VCCD). Over the decades that have followed, the unbackfilled Indian Springs Mound excavations were left to the elements and the mound experienced significant damage from erosion.

Indian Springs Mound after reconstructionA renewed interest in the Collins site by archaeological researchers at the U of I has occurred in recent years culminating in 2013 with Dr. Timothy Pauketat and graduate student Amanda Butler receiving permission from the VCCD to conduct additional excavations at the Collins site.  Their investigations included excavations in the floodplain village area but they also focused on reopening the original excavation areas of the Indian Springs Mound to gain possible new insights on this mound. An important aspect associated with the planning of these new investigations was the planned ISAS reconstruction of the mound to its original, pre-excavation condition following the excavations. Such reconstruction, with coordination and assistance from the VCCD, was made possible with the support of Dr. Thomas Emerson and the Illinois State Archaeological Survey and overseen by Dr. Pauketat.  The new mound excavations reexamined former excavation wall profiles and re-exposed the remnant portions of the burned structure. As a result, the current researchers are positing new interpretations regarding various construction and event sequences that occurred in and prior to mound construction.

Importantly, the mound reconstruction work has been completed. The first stage of the reconstruction was to use heavy equipment to deposit an approximate one foot thick layer of sand over the base of the excavations to provide a layer distinct from the subsoil and intact mound fill. This was followed by transferring existing backdirt piles into the excavation area followed by additional truckloads of dirt fill to complete the mound reconstruction. The VCCD has planted a vegetation cover to control erosion of the newly configured mound. This successful project, carried out with the efforts of many individuals from several organizations, has resulted not only in important new archaeological information but has transformed a formerly badly disturbed and eroded mound to its former shape that can once again serve as a reminder and a respected symbol of Illinois’ prehistoric past.