This is an update to a previously archived data set, which is available at https://doi.org/10.13020/4zwr-t415. Here, additional sites for 2021, and additional data for 2022 and 2023 are given. There will be no further updates. 570 station occupations occurred along Lake Superior’s southwest shoreline where data were collected from Lake Superior and its watershed in the region generally between Duluth-Superior and Ashland, WI. Parameters include forms of carbon, nitrogen, and phosphorus, along with total suspended solids, chlorophyll, and phycocyanin.

The National Lakes Assessment (NLA) is a statistical survey of the condition of our nation's lakes, ponds, and reservoirs. It is designed to provide information on the extent of lakes that support healthy biological condition and recreation, estimate how widespread major stressors are that impact lake quality, and provide insight into whether lake quality is improving or getting worse. This dataset is an archived (zipped) file comprised of chemical, physical and biological files used in developing the NLA 2022 report. Sampling was conducted in the summer of 2022 at approximately 1000 sites in the conterminous U.S. Sites were selected using a statistical survey (probabilistic) design. The files include water chemistry, profile data, benthic macroinvertebrates, physical habitat, landscape metrics, secchi depth, tropic status, zooplankton, etc. Users are encouraged to visit the NARS data webpage for updates to data files and data from other surveys. https://www.epa.gov/national-aquatic-resource-surveys/data-national-aquatic-resource-surveys Citation for the NLA 2022 archived data: U.S. Environmental Protection Agency. 2024. National Lakes Assessment: The fourth collaborative survey of lakes in the United States. EPA 841-R-24-006. U.S. Environmental Protection Agency, Office of Water and Office of Research and Development. https://nationallakesassessment.epa.gov/webreport EPA encourages users who are publishing subsets of the data (say as part of a journal article publication) to include the above citation. EPA also encourages users of the data to include the following acknowledgement: “The National Lakes Assessment 2022 data were a result of the collective efforts of dedicated field crews, laboratory staff, data management and quality control staff, analysts and many others from EPA, states, tribes, federal agencies, universities, and other organizations. Please contact nars-hq@epa.gov with any questions.”. Citation information for this dataset can be found in Data.gov's References section.

This dataset contains modeled daily lake area, volume, constituent mass, and biogeochemical rates for 3,692 lakes in the Northern Highlands Lake District (NHLD) for one retrospective model run (1986-2010) and 12 model runs under future climate scenarios. This dataset was created using published tools developed to simulate detailed hydrological and biogeochemical fluxes for thousands of lakes and reservoirs over large spatiotemporal scales. The lake hydrology model utilized a computationally-efficient integrated surface water and groundwater modeling framework that informed a lake water budget model incorporating daily hydrologic inputs and exports from individual lakes within the modeling domain. The lake biogeochemical model was informed by the hydrologic information and was built upon a simple lake energy budget, constituent loading, and lake biogeochemical model to track carbon storage and processing for all lakes within the NHLD modeling domain. Our one retrospective model run was driven by historic meteorological data and the projected model runs were driven by projected future climate scenario periods that are representative through the year 2100. For more details on the historic and projected driver data and model set up, please see Zwart et al. (year and DOI to be entered once MS is published).

This dataset contains modeled daily lake area, volume, constituent mass, and biogeochemical rates for 3,692 lakes in the Northern Highlands Lake District (NHLD) for one retrospective model run (1986-2010) and 12 model runs under future climate scenarios. This dataset was created using published tools developed to simulate detailed hydrological and biogeochemical fluxes for thousands of lakes and reservoirs over large spatiotemporal scales. The lake hydrology model utilized a computationally-efficient integrated surface water and groundwater modeling framework that informed a lake water budget model incorporating daily hydrologic inputs and exports from individual lakes within the modeling domain. The lake biogeochemical model was informed by the hydrologic information and was built upon a simple lake energy budget, constituent loading, and lake biogeochemical model to track carbon storage and processing for all lakes within the NHLD modeling domain. Our one retrospective model run was driven by historic meteorological data and the projected model runs were driven by projected future climate scenario periods that are representative through the year 2100. For more details on the historic and projected driver data and model set up, please see Zwart et al. (year and DOI to be entered once MS is published).

Data on carbon and nutrient processing in key locations and over seasonal time scales can provide critical information about the concentrations and potential utilization rates of bioavailable constituents that are known to have a role in cyanobacteria harmful algal blooms (cyanoHABs). Laboratory experiments were performed to measure seasonal nutrient processing rates of carbon, nitrogen and phosphorus in river water and bottom sediments collected just upstream of the Next Generation Water Observing System (NGWOS) location at Starved Rock Lock and Dam USGS gaging station number 05553700 on the Illinois River. This site was chosen based on previous development of cyanoHABs. Sediments and unfiltered river water were collected during the spring (April), summer (August), and fall (November) of 2022 then shipped to Boulder, CO for laboratory experiments. River water alone and river water combined with < 2-millimeter sieved sediments were assessed under ambient nutrient conditions and nitrogen amended conditions to determine rates of production or consumption for the following processes: 1) aerobic carbon dioxide production, oxygen consumption, and aqueous nutrient transformations, and 2) anaerobic denitrification, carbon dioxide production, methanogenesis, and aqueous nutrient transformations. Modifications to certain experiments were made in November 2022 based on results from the April and August 2022 experiments and are noted in the metadata steps. Background sediment total carbon and nitrogen content, deionized water and potassium chloride extractable sediment nutrient concentrations, and river water nutrient concentrations were measured during each collection. Sequential extractions of the sieved sediment were performed using deionized water, sodium bicarbonate, sodium hydroxide, and hydrochloric acid to measure phosphorus content of the sediment during the various steps.

Phosphorus, nitrogen, chloride, and suspended-sediment loads, in 24 U.S. tributaries of the Great Lakes, were estimated using U.S. Geological Survey (USGS) data from the Great Lakes Restoration Initiative (GLRI) monitoring program for the period Oct 2010 through Sept 2023 (USGS water years 2011-23). Specific water-quality constituents include total phosphorus, orthophosphate, particulate phosphorus, total nitrogen, nitrate plus nitrite, ammonium plus ammonia, chloride, and suspended sediment. Concentrations and loads, including actual and flow-normalized estimates, were estimated with Weighted Regression on Time, Discharge, and Season (WRTDS). Results are reported at daily and annual time steps in this data release and via an interactive web application (https://rconnect.usgs.gov/glritrends). This data release is an update of a previous version for water years 2011-20. Major changes include the addition of data from water years 2021-23 and the addition of chloride to the constituents.

This data release contains a data compilation and analysis of the hydrogeology in the U.S. portion of the Lake Superior watershed, for the purpose of providing background data for future study and modeling of groundwater and contaminant movement in the watershed. The data support an analysis of groundwater contributions to the water budget of Lake Superior and provide hydrogeologic context for future modeling and sampling of groundwater in the region. The data release contains three child items: Baseflow analysis for tributaries to Lake Superior from 1946 to 2020; Geohydrology data for groundwater analysis in the Lake Superior Watershed; and Groundwater wells from Minnesota, Wisconsin, and Michigan state databases and the U.S. Geological (USGS) National Water Information System (NWIS) database with static water level data within 10km of the Lake Superior watershed.

This data release contains a data compilation and analysis of the hydrogeology in the U.S. portion of the Lake Superior watershed, for the purpose of providing background data for future study and modeling of groundwater and contaminant movement in the watershed. The data support an analysis of groundwater contributions to the water budget of Lake Superior and provide hydrogeologic context for future modeling and sampling of groundwater in the region. The data release contains three child items: Baseflow analysis for tributaries to Lake Superior from 1946 to 2020; Geohydrology data for groundwater analysis in the Lake Superior Watershed; and Groundwater wells from Minnesota, Wisconsin, and Michigan state databases and the U.S. Geological (USGS) National Water Information System (NWIS) database with static water level data within 10km of the Lake Superior watershed.

This U.S. Geological Survey (USGS) data release provides surface water quality and groundwater elevation data collected by USGS personnel within the Central Pine Barrens (CPB) Region of Suffolk County, New York, from October 1, 2021 through September 30, 2022. The data were collected in cooperation with the Central Pine Barrens Commission and the Town of Brookhaven as part of a comprehensive water resources monitoring program during 2017 to 2023. Water quality and quality assurance data from seven sites on two rivers (Carmans River- five sites and Peconic River- two sites) in the CPB are included. Carmans River sites were sampled four times throughout the year (fall, winter, spring, and summer) and Peconic River sites were sampled twice throughout the year (fall and spring). Water quality field parameters measured during each site visit are included. All samples were analyzed for nutrients, major inorganics, and alkalinity. An annual set of organic samples for pesticide and pharmaceutical analysis were collected at one Carmans River site and two Peconic River sites. Periodic groundwater elevation data collected from six CPB wells are included. Continuous (15-minute interval) groundwater elevation data are included for one of the six wells.