Publications

During prolonged periods of above-average precipitation, rising groundwater levels have the potential to cause damage to and interfere with underground infrastructure and building foundations. To understand the relations between precipitation and groundwater in the vicinity of Lake Nokomis, the U.S. Geological Survey, in collaboration with the University of Minnesota, quantified five...

The geologic history and anthropogenic modifications of Minnesota’s Wild Rice River have caused major morphological adjustments, which induce erosion and excess fluvial sediment transport. The excess sediment deposits in the lower Wild Rice River, exacerbating flooding. To help mitigate these problems, the Wild Rice Watershed District has future plans to implement a river restoration on...

The U.S. Geological Survey and Milwaukee Metropolitan Sewerage District in Wisconsin have an ongoing partnership to monitor water quality in streams in the Milwaukee metropolitan area and to assess the effects of stream restoration on habitat and water quality. Because sediment nutrient dynamics can improve or further impair water quality, we measured sediment nitrogen and phosphorus...

Mercury (Hg) contamination of aquatic food webs is controlled in part by the formation and accumulation of toxic and bioaccumulative methylmercury (MeHg). MeHg production is mediated by metabolically diverse microorganisms carrying the hgcAB gene pair, while the demethylation reaction is mediated by several biotic and abiotic processes. However, the relative importance of these two...

The history-matching approach to parameter estimation with models enables a powerful offshoot analysis of data worth—using the uncertainty of a model forecast as a metric for the worth of data. Adding observation data will either have no impact on forecast uncertainty or will reduce it. Removing existing data will either have no impact on forecast uncertainty or will increase it. The...

This report chapter summarizes the effect of hydroclimatic variability of annual peak streamflow in Minnesota and is part of a larger U.S. Geological Survey multistate study to assess potential nonstationarity in annual peak streamflows across the Midwest. Spatial and temporal patterns were examined for nonstationarity in annual peak streamflow, daily mean streamflow, and modeled...

Apex marine predators, such as toothed whales and large petrels and albatrosses, ingest mercury (Hg) primarily in the form of methylmercury (MeHg) via prey consumption, which they detoxify as tiemannite (HgSe). One of the most intriguing current questions in Hg research is how more abundant lower trophic level predators detoxify MeHg, particularly in marine environments where tissue Hg...

In 2011–13, the U.S. Geological Survey (USGS) conducted a study of the hydrogeomorphic setting and hydrodynamic conditions of the lower Sheboygan River and island complex within the backwater zone of Lake Michigan. Analyses of historical aerial photographs from 1938–2010 indicated that the Wildwood Islands complex had experienced mainly erosion and what was mainly one island in 1938 had...

Illustration of U.S. Geological Survey science at breccia pipe mines in the Grand Canyon region. The upper left portion shows a cross section of a breccia pipe and rock layers (far upper left) in a panoramic view of the Grand Canyon with upper right depicting rock pinnacles the Havasupai Tribe call Wi’i Gileeva. The right portion depicts a spring. The Colorado River bisects the...

A thorough understanding of fluvial sediment transport is essential for addressing key environmental issues such as aquatic habitat degradation, flooding, excess nutrients, and challenges with river restoration. Fluvial sediment samples are valuable for addressing these concerns, but their collection is often impractical across all rivers and timeframes of interest. In addition...

Treated municipal wastewater effluent is an important pathway for Contaminants of Emerging Concern (CEC) to enter aquatic ecosystems. As the aging wastewater infrastructure in many industrialized countries requires upgrades or replacement, assessing new treatment technologies in the context of CEC effects may provide additional support for science-based resource management. Here, we used...

This study presents a synthesis of the hydrogeology in the U.S. Lake Superior watershed and the contribution of groundwater to the water budget of the U.S. Lake Superior basin. Much of the shoreline of Lake Superior in Minnesota and Michigan is composed of hydrogeologic units contributing very little direct groundwater discharge to the lake. Groundwater in watersheds adjacent to the lake...