You can install nawqa from Github with:
devtools::install_github("jsta/nawqa")library(nawqa)#> Observations: 502
#> Variables: 71
#> $ `SU Year` <dbl> NA, NA, NA, 1991, 1991, 199…
#> $ `Study Unit` <chr> NA, NA, NA, "ACFB", "ACFB",…
#> $ `Site ID` <chr> NA, NA, NA, "02332830", "02…
#> $ `Site Name` <chr> NA, NA, NA, "West Fork Litt…
#> $ `Area\n(km2)` <dbl> NA, NA, NA, 47.33100, 3032.…
#> $ `Long-term mean annual runoff\n(in)` <dbl> NA, NA, NA, 34.45922, 33.84…
#> $ `Water years` <chr> NA, NA, NA, "1994-95", "199…
#> $ `Mean Flow (ft3/s)` <dbl> NA, NA, NA, 31.00479, 2046.…
#> $ Ammonia <chr> "Model", NA, NA, "AMLE", "A…
#> $ X__1 <chr> "Load\n(kg/year)", NA, NA, …
#> $ X__2 <chr> "Annual\nyield\n(kg/km2)", …
#> $ X__3 <chr> "Mean Concentration (mg/L)"…
#> $ X__4 <dbl> NA, NA, NA, 0.15395873, 0.0…
#> $ X__5 <chr> NA, "Time-wtd", NA, NA, NA,…
#> $ X__6 <dbl> NA, NA, NA, 0.07676329, 0.0…
#> $ X__7 <chr> "Percentile", "Flow-wtd", N…
#> $ X__8 <chr> NA, "Time-wtd", NA, "72", "…
#> $ `Nitrite + Nitrate` <chr> "Model", NA, NA, "AMLE", "A…
#> $ X__9 <chr> "Load\n(kg/year)", NA, NA, …
#> $ X__10 <chr> "Annual\nyield\n(kg/km2)", …
#> $ X__11 <chr> "Mean Concentration (mg/L)"…
#> $ X__12 <dbl> NA, NA, NA, 1.4045180, 0.31…
#> $ X__13 <chr> NA, "Time-wtd", NA, NA, NA,…
#> $ X__14 <dbl> NA, NA, NA, 1.4782219, 0.31…
#> $ X__15 <chr> "Percentile", "Flow-wtd", N…
#> $ X__16 <chr> NA, "Time-wtd", NA, "70", "…
#> $ `Total Nitrogen` <chr> "Model", NA, NA, "AMLE", "A…
#> $ X__17 <chr> "Load\n(kg/year)", NA, NA, …
#> $ X__18 <chr> "Annual\nyield\n(kg/km2)", …
#> $ X__19 <chr> "Mean Concentration (mg/L)"…
#> $ X__20 <dbl> NA, NA, NA, 2.6707518, 0.42…
#> $ X__21 <chr> NA, "Time-wtd", NA, NA, NA,…
#> $ X__22 <dbl> NA, NA, NA, 2.1838371, 0.42…
#> $ X__23 <chr> "Percentile", "Flow-wtd", N…
#> $ X__24 <chr> NA, "Time-wtd", NA, "70", "…
#> $ Orthophosphate <chr> "Model", NA, NA, "AMLE", "M…
#> $ X__25 <chr> "Load\n(kg/year)", NA, NA, …
#> $ X__26 <chr> "Annual\nyield\n(kg/km2)", …
#> $ X__27 <chr> "Mean Concentration (mg/L)"…
#> $ X__28 <dbl> NA, NA, NA, 0.08107186, 0.0…
#> $ X__29 <chr> NA, "Time-wtd", NA, NA, "<"…
#> $ X__30 <dbl> NA, NA, NA, 0.04572832, 0.0…
#> $ X__31 <chr> "Percentile", "Flow-wtd", N…
#> $ X__32 <chr> NA, "Time-wtd", NA, "62", "…
#> $ `Total Phosphorus` <chr> "Model", NA, NA, "AMLE", "A…
#> $ X__33 <chr> "Load\n(kg/year)", NA, NA, …
#> $ X__34 <chr> "Annual\nyield\n(kg/km2)", …
#> $ X__35 <chr> "Mean Concentration (mg/L)"…
#> $ X__36 <dbl> NA, NA, NA, 0.45089282, 0.0…
#> $ X__37 <chr> NA, "Time-wtd", NA, NA, NA,…
#> $ X__38 <dbl> NA, NA, NA, 0.16069655, 0.0…
#> $ X__39 <chr> "Percentile", "Flow-wtd", N…
#> $ X__40 <chr> NA, "Time-wtd", NA, "70", "…
#> $ `Land Use` <chr> "Category", NA, NA, "Partia…
#> $ X__41 <chr> "Population density (per km…
#> $ X__42 <chr> "Percent of upstream waters…
#> $ X__43 <chr> NA, "Cropland", NA, "3.1947…
#> $ X__44 <chr> NA, "Pasture", NA, "28.4584…
#> $ X__45 <chr> NA, "Forest", NA, "67.25603…
#> $ X__46 <chr> NA, "Range", NA, "0", "0", …
#> $ X__47 <chr> NA, "Other Undeveloped", NA…
#> $ X__48 <chr> NA, "Total", NA, "100", "10…
#> $ `Nutrient Input (kg/km2)` <chr> "Nitrogen", "Atmospheric de…
#> $ X__49 <chr> NA, "Farm fertilizer", NA, …
#> $ X__50 <chr> NA, "Non-farm fertilizer", …
#> $ X__51 <chr> NA, "Manure", NA, "7555.091…
#> $ X__52 <chr> NA, "Total", NA, "8801.3924…
#> $ X__53 <chr> "Phosphorus", "Farm fertili…
#> $ X__54 <chr> NA, "Non-farm fertilizer", …
#> $ X__55 <chr> NA, "Manure", NA, "2436.268…
#> $ X__56 <chr> NA, "Total", NA, "2630.4749…