Chemical composition of fish bones can be used to trace fish migrations and other movements (e.g., use of tributaries for spawning). Chemical composition of water is required to be able to trace fish migrations or movements to particular rivers or streams. Because water chemistry can change over time due to changes in land use, tectonic movements that alter groundwater pathways, pollution, industrial activity, and potentially other sources, periodic re-assessment of water chemistry is required. Here we present data on concentrations of common elements for several tributary streams to Lake Michigan, Lake Erie, and Lake Ontario collected in 2017 and 2018. These data will be useful to anyone desiring to track fish usage of these tributaries or changes in water chemistry resulting from land use changes.

This data release provides water chemistry results and quality assurance data for samples collected from Great Lakes tributaries in the states of Minnesota, Wisconsin, Michigan, Indiana, Ohio, and New York. In total, 158 chemicals were analyzed which are primarily pharmaceuticals. Between one and four water samples were collected at 37 sampling locations between November 2017 and July 2018 resulting in a total of 87 environmental, 95 field replicate, and 15 field blank samples. Of the 158 chemicals analyzed, 23 chemicals were detected in at least one regular sample. Detections per site ranged from 0 to 12 chemicals at concentrations of 1.56 to 30900 nanograms per liter. Sample collection and analysis was performed by the U.S. Geological Survey and summarized in the associated journal article (https://doi.org/10.1002/etc.5403). More detailed method descriptions will be published in the future.

This dataset describes the hydrogeomorphic structure and lake-tributary mixing in three intermediate-sized Lake Michigan rivermouths: Ford River, Manitowoc River, and Pere Marquette River. Data were collected from May to October 2011. Water chemistry variables were measured with a multiparameter sonde along longitudinal, lateral, and vertical transects. Magnesium, boron, and stable water isotope concentrations were also determined from grab water samples at particular depths.

This dataset describes the hydrogeomorphic structure and lake-tributary mixing in three intermediate-sized Lake Michigan rivermouths: Ford River, Manitowoc River, and Pere Marquette River. Data were collected from May to October 2011. Water chemistry variables were measured with a multiparameter sonde along longitudinal, lateral, and vertical transects. Magnesium, boron, and stable water isotope concentrations were also determined from grab water samples at particular depths.

In the Great Lakes basin, there are numerous organizations undertaking scientific monitoring and research efforts with the goal of identifying threats and evaluating management strategies that will protect and restore the Great Lakes ecosystem. Coordination among all these stakeholders is a challenge, and having a centralized location where researchers and managers can identify relevant scientific activities and access fundamental information about these activities is crucial for efficient management. The Science in the Great Lakes (SiGL) Mapper was a map-based discovery tool that spatially displayed basin-wide multidisciplinary monitoring and research activities conducted by both USGS and partners from all five Great Lakes. It was designed to help Great Lakes researchers and managers strategically plan, implement, and analyze monitoring and restoration activities by providing easy access to historical and on-going project metadata while allowing them to identify gaps (spatially and topically) that have been underrepresented in previous efforts or need further study. SiGL provided a user-friendly and efficient way to explore Great Lakes projects and data through robust search options while also providing a critical spatial perspective through its interactive mapping interface.

In the Great Lakes basin, there are numerous organizations undertaking scientific monitoring and research efforts with the goal of identifying threats and evaluating management strategies that will protect and restore the Great Lakes ecosystem. Coordination among all these stakeholders is a challenge, and having a centralized location where researchers and managers can identify relevant scientific activities and access fundamental information about these activities is crucial for efficient management. The Science in the Great Lakes (SiGL) Mapper was a map-based discovery tool that spatially displayed basin-wide multidisciplinary monitoring and research activities conducted by both USGS and partners from all five Great Lakes. It was designed to help Great Lakes researchers and managers strategically plan, implement, and analyze monitoring and restoration activities by providing easy access to historical and on-going project metadata while allowing them to identify gaps (spatially and topically) that have been underrepresented in previous efforts or need further study. SiGL provided a user-friendly and efficient way to explore Great Lakes projects and data through robust search options while also providing a critical spatial perspective through its interactive mapping interface.

This data set includes WRTDS nutrient flux trend results and the values of daily streamflow trend results displayed in the Quantile-Kendall plots. For 1995-2015 nutrient trends, the method of generalized flow normalization (FNG) was used which explicitly addresses non-stationary streamflow conditions. For 2005-2015 nutrient trends, the WRTDS trend analyses used the method of stationary flow normalization (FNS) because streamflow nonstationarity is difficult to assess over this shorter duration time frame. The 1995-2015 annual nutrient trends were determined for all five nutrient parameters (TP, SRP, TN, NO23, TKN), and monthly trends were evaluated only for SRP. The 2005-2015 annual nutrient trends were determined for the three parameters TP, SRP, and TN. For the water-quality parameter SRP, monitoring data and trend results were available for 6 of the 10 trend sites. Daily streamflow trends were evaluated for the time-period 1987-2016 at 9 of the study sites, applied as climatic years (years which start April 1 and end March 31) for a period of 29 climatic years (1988 – 2016). Details on the WRTDS method of generalized flow normalization appear in Hirsch and De Cicco (2018) and in Choquette et al. (2019). Details on the Quantile-Kendall plots and their construction appears in Hirsch (2018) and in Appendix A of Choquette et al. (2019). Details regarding interpretations of these trend results and the watershed characteristics upstream of these sites appear in Choquette et al. (2019). The results dataset is presented in 5 parts: 1. AnnualNutrientTrends_1995-2015.csv (WRTDS nutrient flux trend results) 2. MonthlySRPTrends_1995-2015.csv (SRP monthly flux trend results for 6 sites) 3. AnnualNutrientTrends_2005-2015.csv (WRTDS nutrient flux trend results) 4. DailyFlowTrends_1987-2016.zip (Annual streamflow trend results, by site, presented in the Quantile-Kendall plots) 5. Quantile-Kendall-plots.pdf (plots showing 1988-2016 streamflow trend results) References: Choquette, A.F., Hirsch, R.M., Murphy, J.C., Johnson, L.T., and Confesor, R.B. Jr., 2019, Tracking changes in nutrient delivery to western Lake Erie: approaches to compensate for variability and trends in streamflow: J. of Great Lakes Research, v. 45, no. 1, p. 21-39, https://doi.org/10.1016/j.jglr.2018.11.012. Hirsch, R.M., 2018, Daily streamflow trend analysis: U.S. Geological Survey Office of Water Information Blog, 38 p., at: https://owi.usgs.gov/blog/Quantile-Kendall/. Hirsch, R.M., and De Cicco, L.A., 2018, EGRET release 3.0, and EGRETci release 2.0, at: https://cran.r-project.org/

The data in this record contains water physical, chemical, and biological vertical observational data from fixed mooring CHRP2 in the central basin of Lake Erie, Great Lakes region during the summer seasons from 2021-06-17 through 2021-09-28. The approximate depth at CHRP2 is 20.0 m. Observations were collected at hourly or sub-hourly time intervals for water temperature and dissolved oxygen and other water quality parameters. The moorings are designed in a U-shape with a spar buoy and a subsurface buoy approximately 300 ft apart. The spar buoy has a surface expression float and holds the upper water column sensors. The subsurface buoy holds the subsurface float and lower water column sensors. The vertical placement of temperature and dissolved oxygen sensors, as well as the spatial location of the mooring, varied from year to year. The total depth of the mooring location is approximated from nautical charts. The data files associated with this accession contain the terms “spar” or “subsurface” to differentiate the two locations for each mooring. The file names end with the time resolution of the data in ISO 8601 format. This mooring location is one of seven CHRP moorings that collected observations during the 2021 summer season. Note, these moorings have been deployed in Lake Erie's central basin during the open water season since 2017. In 2021, the CHRP7 mooring was not deployed.