readWQP: Read EPA Water Quality Portal Data

In utah-dwq/wqTools: A Collection of R Tools for Utah Division of Water Quality

Read EPA Water Quality Portal Data

Description

This function extracts water quality data from EPA's Water Quality Portal based on user argument inputs. Note that connections to the WQP occassionally time out during download. This function tries to download requested files up to 10 times before exiting. All arguments except type are optional, but at least one should be provided to limit download size and prevent errors connecting to WQP. Note that some, but not all, special characters in characteristic names have been accounted for. If in doubt, use the WQP web interface to determine the appropriate sytax for odd characteristic names. This function coerces non-numeric values in ResultMeasureValue column (for result & narrowresult type queries). This may generate NA values with a warning for special characters.

Usage

readWQP(
  type = "result",
  ...,
  print = FALSE,
  coerce_num = FALSE,
  url_only = FALSE,
  auid = NULL
)

Arguments

type	Data type to read. One of "result", "narrowresult", "sites", "activity", "detquantlim", or "project".
...	additional arguments to be passed to WQP query path. See https://www.waterqualitydata.us/portal/ for optional arguments.
print	Logical. Print summary table of sites & characteristics (only for result or narrowresult types).
coerce_num	Logical. If TRUE the ResultMeasureValue column in result and narrowresult type reads is coerced to numeric values. This will generate NAs in the ResultMeasureValue column for non-numeric values. Defaults to FALSE.
url_only	Logical. If FALSE (default) read and return data. If TRUE, return just the query url.
auid	Optional. A vector of Utah DWQ assessment unit identifiers for which to query data. Note that siteid is ignored if auid is specified.
start_date	Query start date in "mm/dd/yyyy" format.
end_date	Query end date in "mm/dd/yyyy" format.

Value

A data frame of WQP data

Examples

# Read some data from Mantua Reservoir (2016-2018)
nr=readWQP(type="narrowresult", siteid=c("UTAHDWQ_WQX-4900440","UTAHDWQ_WQX-4900460"),
		  start_date="01/01/2016", end_date="12/31/2018")

# Read just Arsenic, Cadmium, and DO, all dates
nr=readWQP(type="narrowresult",
		  siteid=c("UTAHDWQ_WQX-4900440","UTAHDWQ_WQX-4900460"),
		  characteristicName=c("Arsenic","Cadmium","Dissolved oxygen (DO)"))

# Read all Total dissolved solids statewide (2016-2018) (& note statecode for Utah)
tds_sw=readWQP(type="result",
			  statecode="US:49",
			  characteristicName="Total dissolved solids",
			  start_date="01/01/2016", end_date="12/31/2018",
			  print=F)

# Read data by assessment unit identifiers
utah_lake_nr=readWQP(type="narrowresult",
		auid=c('UT-L-16020201-004_01', 'UT-L-16020201-004_02'),
		start_date="01/01/2016", end_date="12/31/2018",
		siteType=c("Lake, Reservoir, Impoundment","Stream"),
		print=F)
utah_lake_sites=readWQP(type="sites",
 		auid=c('UT-L-16020201-004_01', 'UT-L-16020201-004_02'),
 		siteType=c("Lake, Reservoir, Impoundment","Stream"),
 		print=F)
buildMap(sites=utah_lake_sites)


# Read DWQ's sites
sites=readWQP(type="sites", statecode="US:49", organization="UTAHDWQ_WQX", siteType=c("Lake, Reservoir, Impoundment","Stream"))
plot(LatitudeMeasure~LongitudeMeasure, sites[sites$LatitudeMeasure>0 & sites$LongitudeMeasure<0,])

utah-dwq/wqTools documentation built on July 18, 2024, 6:45 a.m.