Physical and chemical properties of water and sediments, Grand Portage and Wauswaugoning Bays, Lake Superior, Grand Portage Indian Reservation, northeastern Minnesota, 1993-96

Abstract

This report is a compilation of data on the physical and chemical properties of water and sediments in Grand Portage and Wauswaugoning Bays of Lake Superior along the shoreline of the Grand Portage Indian Reservation. The data were collected during 1993-96 by the U.S. Geological Survey in cooperation with the Grand Portage Indian Reservation. The data include: (1) temperature, pH, and specific conductance measurements and dissolved oxygen concentrations; (2) Secchi disk transparency, alkalinity, and turbidity measurements; (3) fecal Coliform and fecal Streptococcal bacteria colony counts (per 100 milliliters of sample water); (4) major and minor ion, nutrient, and trace-metal concentrations; (5) dissolved and suspended residue concentrations; (6) pesticide, phenol, and asbestos concentrations; (7) suspended sediment trace-metal concentrations; and (8) bottom sediment trace-metal concentrations. Water samples were collected from nine sites; suspended and bottom sediment samples were collected from five sites. The data in this report can be used to evaluate present water-quality conditions and as a reference to monitor potential long-term changes in these conditions. Introduction The Grand Portage Indian Reservation (hereinafter referred to as the Reservation) is located in extreme northeastern Minnesota along the north shore of Lake Superior (fig. 1). The Reservation has an area of about 56,000 acres and is mostly forest. Total population of the Reservation is about 350 people (Rick Novitsky, Grand Portage Indian Reservation Tribal Council, oral commun., 1994). Most homes, businesses, tourist and historical attractions, are located in the community of Grand Portage, along U.S. Highway 61, and east of Mineral Center along County State Aid Highway 17. This report provides the Reservation Tribal Council important water-quality information about Grand Portage and Wauswaugoning Bays (fig. 1). The two bays have important aesthetic, fishery, and water-supply values. Grand Portage Bay is a spawning and nursery area for a variety of fish species, which include lake trout, lake whitefish, lake herring, and non-game species. Wauswaugoning Bay is the site of a recently constructed (1996) community water-supply system. The intake for this system is at a depth of about 50 ft (Steve Forthun, Indian Public Health Service, oral commun., 1997) at the southeastern tip of Hat Point (fig. I)The purpose of this report is to present data on the physical and chemical properties of water and sediments in Grand Portage and Wauswaugoning Bays of Lake Superior along the shoreline of the Grand Portage Indian Reservation. The data will serve as a reference to monitor potential changes in water quality and sediment chemistry in the bays. The data were collected during 1993-96 from one site in Wauswaugoning Bay and from eight sites in Grand Portage Bay (fig. 1 inset). The data include: (1) temperature, pH, and specific conductance measurements and dissolved oxygen concentrations at eight sites; (2) Secchi disk transparency at one site, alkalinity, and turbidity measurements at three sites; (3) fecal Streptococcal and fecal Coliform bacteria colony counts at six sites; (4) major and minor ion, nutrient, and trace-metal concentrations at three sites; (5) dissolved and suspended residue concentrations at three sites; (6) pesticide, phenol, and asbestos concentrations at one site; (7) suspended sediment trace-metal concentrations at one site; and (8) bottom sediment trace-metal concentrations at four sites. 89°52'30 89°45' 89°37'30 89°30'