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              Illinois EPA Phase I – Diagnostic Study
Clean Lakes Program Lake Paradise
March 2004
Final Report
13
The interaction between surface water in the reservoir and groundwater in the watershed
appears to be variable, but may be important in limited areas where the streams have eroded into
sand and gravel layers in the glacial drift or where sand and gravel layers intersect the lake.
Soils
The soil in Coles County formed in loess, glacial till, alluvium, lacustrine sediments, and
residuum, (USDA, 1993). Loess is the most extensive parent material in the county. In most
areas the loess occurs as two layers. The upper layer, or Peoria Loess, was deposited during the
Woodfordian Substage of the Wisconsinan age, about 22,000 to 12,500 years ago. The Roxana
Silt underlies the Peoria Loess. The Roxana Silt was deposited more than 28,000 years ago
(Willman and Frye, 1970). The loess on summits in the western part of the county is generally
more than 60 inches thick.
The major soil associations in the Lake Paradise watershed and surrounding area are the
Drummer-Raub-Dana Association, the Xenia-Fincastle-Toronto Association, and the Miami-
Russell Association.
The Drummer-Raub-Dana Association includes nearly level and gently sloping ridges,
poorly drained to moderately well drained, silty soils formed in loess and glacial outwash or in
loess and glacial till on till plains. The soils on ridges have slopes that are 100 to 800 feet long.
The low areas are nearly level to depressional. This association makes up 82 percent of the
watershed at the north of the watershed. Within Coles County, this association is comprised of
about 52 percent Drummer soils, 26 percent Raub soils, 21 percent Dana soils, and 1 percent
soils of minor extent. Slopes range from 0 to 5 percent. However, the Dana soils do not comprise
a significant portion of the Lake Paradise watershed. Most of this association is used for
cultivated crops, but some areas are used for hay and pasture.
The Xenia-Fincastle-Toronto Association is comprised of nearly level and gently sloping,
moderately well drained and somewhat poorly drained, silty soils that formed in loess and glacial
till on till plans. This association consists of soils on crests, interfluves, side slopes, head slopes,
and broad summits on till plains. Slopes range from 0 to 10 percent. This association makes up
about 12 percent of the watershed and is found on both the east and west sides of the lake. It is
comprised of about 38 percent Xenia soils, 22 percent Fincastle soils, 19 percent Toronto soils,
and 21 percent soils of minor extent. The gently sloping, moderately well drained Xenia soils are
found on the sides of ridges below the nearly level, somewhat poorly drained Fincastle and
Toronto soils. Most of this association is used for cultivated crops, but some areas are used for
hay, pasture, or woodland.
The Miami-Russell Association is comprised of gently sloping to very steep, well
drained, loamy and silty soils formed in glacial till or in loess and glacial till on till plains. This
association makes up 6 percent of the watershed. It is comprised of about 64 percent Miami soils,
12 percent Russell soils, and 24 percent soils of minor extent. The moderated sloping to very