Nutrients and Major-Ions Measured in Water-Quality Samples Collected from Four North Texas Reservoirs (ver. 3.0, September 2021)
Dates
Publication Date
2019-09-16
Start Date
2015-10-29
End Date
2018-09-27
Revision
2020-09-30
Last Revision
2021-09-30
Citation
Trevino, J.M., Petersen, C.B., and Churchill, C.J., 2019, Nutrients and Major-Ions Measured in Water-Quality Samples Collected from Four North Texas Reservoirs (ver. 3.0, September 2021): U.S. Geological Survey data release, https://doi.org/10.5066/P9VTMVC0.
Summary
In cooperation with Dallas Water Utilities (DWU), the U.S. Geological Survey (USGS) measures nutrient and major-ion concentrations in selected reservoirs in north Texas. This data release documents water-quality data obtained from Ray Hubbard Lake, Grapevine Lake, Ray Roberts Lake, and Lake Lewisville during water years 2016-20. In addition to nutrient and major-ion concentrations, water-quality field properties and other selected constituents measured in the water-quality samples collected from these reservoirs are documented. The study began in water year 2016 (WY16) with monthly sampling of Ray Hubbard Lake. A water year is defined as the 12-month period from October 1 through September 30 and is designated by the calendar year [...]
Summary
In cooperation with Dallas Water Utilities (DWU), the U.S. Geological Survey (USGS) measures nutrient and major-ion concentrations in selected reservoirs in north Texas. This data release documents water-quality data obtained from Ray Hubbard Lake, Grapevine Lake, Ray Roberts Lake, and Lake Lewisville during water years 2016-20. In addition to nutrient and major-ion concentrations, water-quality field properties and other selected constituents measured in the water-quality samples collected from these reservoirs are documented.
The study began in water year 2016 (WY16) with monthly sampling of Ray Hubbard Lake. A water year is defined as the 12-month period from October 1 through September 30 and is designated by the calendar year in which it ends. During this first year, water-quality samples were analyzed for nutrients only (nitrogen, phosphorous, and multiple species of each nutrient). In water year 2017 (WY17), the study design changed to quarterly sampling, expanded to include Grapevine Lake, and added the analysis of major ions (Calcium, Chloride, Fluoride, Magnesium, Potassium, Silica, Sodium, and Sulfate). In water year 2018 (WY18) to present, the study design further expanded to include quarterly sampling of Ray Roberts Lake and Lake Lewisville.
For this study, each reservoir currently (2021) has eight sampling sites. Water years 2018, 2019, and 2020 also include water-quality data collected for the USGS Zebra Mussel Monitoring Program for Texas for all four reservoirs. Water-quality samples are collected at a minimum of five equidistant depths, including top and bottom depths, at each site. Samples are analyzed for nutrients, major ions, and bromide by the USGS National Water Quality Laboratory (NWQL) in Denver, Colorado. Water-quality field properties (dissolved oxygen, pH, specific conductance, temperature, and Secchi depth) are also measured at each sampling site.
This dataset includes all 7,756 samples from the original data release for the previous water years, plus 1,933 additional samples. NOTE: While the previous version is available from the author, all the records from the previous version can be found in version 3.0
First posted: September 16, 2019 (available from author)
Revised: September 30, 2020 (version 2.0)
Revised: September 30, 2021 (version 3.0)
Click on title to download individual files attached to this item.
DWU Nutrients Study 20.xml “Metadata” Original FGDC Metadata
View
226.13 KB
application/fgdc+xml
Site Info.txt
5.33 KB
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WY16_Nutrients.txt
145.63 KB
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WY17_NutrientsIons.txt
127.26 KB
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WY18_NutrientsIons.txt
645.87 KB
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WY19_NutrientsIons.txt
639.41 KB
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WY20_NutrientsIons.txt
610.8 KB
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Version History.txt
1,006 Bytes
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Purpose
This dataset documents water-quality data at North Texas Reservoirs during 2016–18 by providing discrete-depth data for nutrients, major ions, bromide, and other water-quality properties. The data can be used to assess nutrient and major ion concentration over time and at different depths in each reservoir. Nutrients, major ions, and bromide were analyzed using methods described in Patton and Kryskalla (2003, 2011), Fishman and Friedman (1989), and Fishman (1993).
