Limnological monitoring on the UMRS, 1993 1996: LTRMP Havana Field Station

Soballe, D. M., R. H. Wright, and S. W. Stenzel. 2002. Limnological monitoring on the
Upper Mississippi River System, 1993-1996: Long Term Resource Monitoring Program
Havana Field Station. U.S. Geological Survey, Upper Midwest Environmental Sciences
Center, Onalaska, Wisconsin, November 2002. LTRMP 02-P005. 16 pp. + Appendixes
A-F (NTIS# PB2003-101576)

ABSTRACT

Since 1988, the Long Term Resource Monitoring Program (LTRMP) staff have
performed basic limnological field measurements in the Upper Mississippi River System.
The period of this report (1993 -6) includes a major revision of the LTRMP sampling
design in 1993 that added randomization, broader spatial coverage, and increased
monitoring of tributaries and locations that allow monitoring of material transport. Two
significant floods (1993 and 1995) occurred in the reporting period. In 1993, the La
Grange reach of the Illinois River was above the 1940 96 mean river stage for most of
the year and was below flood stage for only three brief periods. The flood in spring 1995
receded sooner than in 1993; however, the 137 m (450.66 feet) peak on May 31, 1995,
was the third highest river elevation recorded at Havana, Illinois. Low dissolved oxygen
levels in the main channel were also notable in 1993-96, with concentrations at or below
5 mg/L observed each year.

KEYWORDS

Annual report, limnology, LTRMP, Mississippi River, water quality