STUDY OF INORGANIC POLLUTANTS MOBILITY FROM CATFISH CREEK 
WATERSHED INTO THE MISSISSIPPI RIVER

Andrew McDonnell, and Chulsung Kim
Department of Natural and Applied Science, Univeisty of Dubuque, Dubuque, IA 52001

The city of Dubuque, located in northeast Iowa on the Mississippi River, historically had 
numerous mining operations, but those industries closed between 30 and 100 years ago. 
One of the major local creeks flows near by city of Dubuque is Catfish Creek which has a 
number of tributaries including Granger Creek, the South Fork of the Catfish, and the 
Middle Fork of the Catfish. The Catfish Creek flows into the Mississippi River running 
through the old abandoned zinc and lead mining area called Fessler Mine which locates 
close to the entrance of the Mississippi River. 

Due to the location of old mine and flow directions of the creek, the Catfish Creek could 
be a potential source of toxic trace metals discharging into the Mississippi River. Efforts 
have been conducted to study the mobility and distribution of trace metals such as lead, 
zinc, manganese, and iron along the Catfish Creek watershed and near the Mississippi 
River entrance area. Various core sediment samples were collected to investigate both the 
surface trace metal distribution and the amount of trace metals as a function of sediment 
depth to monitor the sediment quality alteration for a certain period of sedimentation. In 
addition, water quality parameters including pH, DO, nitrate, nitrite, phosphate, 
conductivity, turbidity, alkalinity, hardness, total suspended solids (TSS) were 
determined over the creek area under three different flow conditions such as riffle, run, 
and pool. 

Based on the findings, the trace metal concentrations are higher as close to the mouth of 
the Mississippi River and the amount of trace metals fluctuate as a function of depth. 
Detailed and updated findings including water quality and trace metal analysis will be 
discussed over the presentation.

Keywords: trace metal, sediment, Mississippi River, water quality