Appendix 1. Methods—Data Retrieval, Screening, and Modification
Contents
Appendix 1 in PDF format
USGS Water-Quality Data Retrieval and Screening
National Stream Water-Quality Monitoring Networks (WQN) Data
National Water Information System (NWISWeb)
Data Modifications
Recensoring
Parameter Codes, Calculated Values, and Order of Precedence for Use
in Analyses
Reference
Appendix 2. Methods—Stations Used in Analysis of Discharge Conditions
Appendix 2 in Excel format (40 KB)
Appendix 2 in Excel file format, zipped (66 KB)
Table
2–1. List of U.S. Geological Survey streamgages used in analysis of streamflow conditions, and summary of analyses performed
Appendix 3. Methods—Flow-Adjusted
Trend Analysis with Tobit Regression in the
S-ESTREND System
Appendix 3 in PDF file format (72 KB)
Contents
Flow-Adjusted Trend Analysis
References
Appendix 4. Methods—Trend Analysis Using
Coupled Statistical Model of Streamflow and
Water Quality
Appendix 4 in PDF file format (65 KB)
Contents
Definition of Non-Flow-Adjusted Trend
Flow-Adjusted Trend in Concentration
Unit Trends and Reference Values
Additional Interpretive Notes
Reference
Appendix 5. Results—Trends in Streamflow,
1975–2003 and 1993–2003
Appendix 5 in Excel format (38 KB)
Appendix 5 in Excel file format, zipped (11 KB)
Table
5–1. Trends in streamflow, and serial correlation of residuals, 1975–2003 and 1993–2003
Appendix 6. Results—Trend Analysis on
Flow-Adjusted Nutrient Concentrations,
1975–2003 and 1993–2003
Appendix 6 in Excel format (96 KB)
Appendix 6 in Excel file format, zipped (29 KB)
Table
6–1. Results of trend analysis on flow-adjusted nutrient concentrations, using Tobit
regression and coupled statistical model of streamflow and water quality, 1975–2003
and 1993–2003
Appendix 7. Results—Annual Load Estimates,
1975–2003, 1993–2003, and Varied Periods of
Record
Individual appendix 7–1a to 7–1n in Excel file format
7-1a, 7-1b, 7-1c, 7-1d, 7-1e, 7-1f, 7-1g, 7-1h, 7-1i, 7-1j, 7-1k, 7-1l, 7-1m, 7-1n
Appendix tables 7–1a to 7–1n in Excel file format, zipped
Appendix tables 7-1a to7-1e (1.87 MB)
Appendix tables 7-1f to 7-1k (315 MB)
Appendix tables 7-1l to 7-1n (1.20 MB)
Tables
7–1. Annual load estimates, confidence intervals, and yields, 1975–2003, 1993–2003, and varied periods of record
7–1A. Annual load estimates, confidence intervals, and yields for total nitrogen, 1975–2003
7–1B. Annual load estimates, confidence intervals, and yields for total nitrogen, 1993–2003
7–1C. Annual load estimates, confidence intervals, and yields for ammonia nitrogen, 1975–2003
7–1D. Annual load estimates, confidence intervals, and yields for ammonia nitrogen, 1993–2003
7–1E. Annual load estimates, confidence intervals, and yields for total Kjeldahl nitrogen,
1975–2003
7–1F. Annual load estimates, confidence intervals, and yields for nitrite-plus-nitrate nitrogen,
1975–2003
7–1G. Annual load estimates, confidence intervals, and yields for nitrite-plus-nitrate nitrogen,
1993–2003
7–1H. Annual load estimates, confidence intervals, and yields for total phosphorus, 1975–2003
7–1I. Annual load estimates, confidence intervals, and yields for total phosphorus, 1993–2003
7–1J. Annual load estimates, confidence intervals, and yields for suspended sediment, 1975–2003
7–1K. Annual load estimates, confidence intervals, and yields for suspended sediment, 1993–2003
7–1L. Annual load estimates, confidence intervals, and yields for total nitrogen, varied
periods of record
7–1M. Annual load estimates, confidence intervals, and yields for nitrite-plus-nitrate
nitrogen, varied periods of record
7–1N. Annual load estimates, confidence intervals, and yields for total phosphorus, varied periods of record
Appendix 8. Results—Trend Analysis on
Nutrient Loads, 1975–2003 and 1993–2003
Appendix 8 in Excel file format (38 KB)
Appendix 8 in Excel file format, zipped (11 KB)
Table
8–1. Results of trend analysis on nutrient loads, calculated by using coupled statistical
model of streamflow and water quality, 1975–2003 and 1993–2003