Floods are responsible for loss of human life and substantial property damage around the world each year, but after floodwaters recede, flood-related hazards may remain. Transport of contaminants, including toxic metals like lead, during floods into previously unaffected areas may pose threats to human and ecological health. In the spring of 2017, the Meramec River and its two main tributaries, the Big River and the Bourbeuse River, experienced a record-breaking flood. During the flood, each river had respective flow increases of 79×, 89×, and 171× pre-flooding conditions. Of concern is that the Big River drains Southeast Missouri’s Lead District (i.e., the “Lead Belt”), a historic lead mining region, which was once the global leader in lead production. Because of its history of lead mining and improper local storage of mining wastes, the Big River’s channel and floodplain sediments are contaminated with lead. Thus, our project goal was to determine if lead contamination stored in Big River sediments may have been transported downstream into the Meramec River basin during the 2017 flood. Water samples were collected during the flood event at several locations on each of the three rivers. Suspended sediments were isolated from the water samples on filters to determine bulk lead and other toxic metal chemistry transported with the flood waters. Sediments were digested in boiling hydrochloric acid, with the subsequent digests being analyzed using an inductively coupled plasma optical emission spectrometer. Our results show increased sediment transport during peak flood flow, but chemical analyses of sediments are ongoing.

Dr. Elizabeth Hasenmueller has been absolutely essential to both the development of this project specifically and my development as a scientist. Her tremendous knowledge of geochemistry, inspiring teaching skills, and wisdom as an advisor have been critical to my successes in the last two years, including in this project.