National Eutrophication Survey

This respository contains a digitally transcribed copy (nes_data.csv) of the National Eutrophication Survey (NES) dataset. The original data can be found in the archival_pdfs folder or by searching: https://www.epa.gov/nscep

Locations

Data

variable name	description	units
pdf	pdf identifier (474 - 477)	integer
pagenum	page number of the pdf	integer
storet_code	identifier which links measurement to coordinate locations	character
state	state where the water body resides	character
name	name of the water body	character
county	county where the water body resides	character
lake_type	natural or impoundment	character
drainage_area	the total drainage area	square kilometers
surface_area	the area of the water surface	sq km
mean_depth	the volume of the water body divided by the surface area in square meters	meters
total_inflow	the mean of the inflows of all tributaries and the immediate drainage	cubic meters per second
retention_time	a mean value determined by dividing the lake volume, in cubic meters, by the mean annual outflow in cubic meters per unit cof time	years or days
retention_time_units	the units of time for each retention entry	years or days
alkalinity	alkalinity	milligrams per liter
conductivity	conductivity	microohms
secchi	secchi	meters
tp	total phosphorus	milligrams per liter
po4	orthophosphate	milligrams per liter
tin	total inorganic nitrogen	milligrams per liter
tn	total nitrogen	milligrams per liter
p_pnt_source_muni	municipal point source phosphorus loading	kilograms per year
p_pnt_source_industrial	industrial point source phosphorus loading	kilograms per year
p_pnt_source_septic	septic point source phosphorus loading	kilograms per year
p_nonpnt_source	nonpoint source phosphorus loading	kilograms per year
p_total	total phosphorus loading	kilograms per year
n_pnt_source_muni	municipal point source nitrogen loading	kilograms per year
n_pnt_source_industrial	industrial point source nitrogen loading	kilograms per year
n_pnt_source_septic	septic point source nitrogen loading	kilograms per year
n_nonpnt_source	nonpoint source nitrogen loading	kilograms per year
n_total	total nitrogen loading	kilograms per year
p_total_out	total phosphorus outlet load	kilograms per year
p_percent_retention	percent phosphorus retention	percent
p_surface_area_loading	phosphorus surface area loading	grams per square meter per year
n_total_out	total nitrogen outlet load	kilograms per year
n_percent_retention	percent nitrogen retention	percent
n_surface_area_loading	nitrogen surface area loading	grams per square meter per year
lat	latitude	decimal degrees
long	longitude	decimal degrees

Workflow

1. Use the nesR package to generate the files in /02_raw_data.

2. Hand check the files in /02_raw_data/merged_data against the pdfs in /01_archival_pdfs.

3. Combine files with 05_analysis_scripts/PDF_Merge.R.

Contributing

We’ve combed the data to try and find all the transciption errors but it’s difficult to catch them all. If you find any errors please open an issue or submit a pull request against the files in /03_qa_data.

References

Stachelek, J., Ford, C., Kincaid, D., King, K., Miller, H. and Nagelkirk, R., 2018. The National Eutrophication Survey: lake characteristics and historical nutrient concentrations. Earth System Science Data, 10(1), pp.81-86. (https://doi.org/10.5194/essd-10-81-2018)

Stachelek, J. (2017). nesR: Scrape Data from National Eutrophication Survey archival PDFs. R package version 0.1. (https://github.com/jsta/nesR) (https://dx.doi.org/10.5281/zenodo.400258)

Stachelek, J. (2017). nesRdata: National Eutrophication Survey Data Package. R package version 0.1. https://github.com/jsta/nesRdata