Download American river-gauge data from USGS

Usage

dod.river.usgs(
  id = "03242350",
  start = NULL,
  end = NULL,
  destdir = ".",
  debug = 0
)

Arguments

id: character value giving the numeric code for the gauge. This defaults to a river in Ohio.
start: an indication of the start time of the requested data window. If provided, this may be in a (non-ambiguous) character form or, better, in a POSIXt object. The "UTC" timezone is assumed. If not provided, start defaults to 1 week before the present time.
end: as for start, but instead for the end date.
destdir: character giving the destination directory in which the downloaded file will be stored. The default value is ".", meaning to store the file in the persent directory.
debug: an integer value indicating the level of debugging. If this exceeds 0, then some debugging messages will be printed. This value is passed down to related functions, but with 1 subtracted for each pass.

Author

Dan Kelley

Examples

if (interactive()) { # pkgdown::build_site() cannot handle downloads
    library(dod)
    destdir <- tempdir(check = TRUE)
    print(destdir)
    file <- dod.river.usgs(start = "2025-08-01", end = "2025-08-08", destdir = destdir, debug = 4)
    lines <- readLines(file)
    skip <- 1 + grep("agency_cd", lines)
    data <- read.delim(text = lines, skip = skip, sep = "\t", header = FALSE)
    # The data at this site, if downloaded during daylight-savings
    # time, are offset from UTC by 4 hours. I'm not sure how to make the server
    # return in UTC.
    time <- as.POSIXct(data$V3, tz = "UTC") + 4 * 3600
    # Convert from feet to metres
    height <- 0.3048 * data$V5
    plot(time, height,
        type = "l", xlab = "Day in year 2025",
        ylab = "River Height [m]"
    )
    mtext(gsub("#[ ]*", "", lines[grep("#    USGS ", lines)]))
    # Clean up space
    unlink(destdir, recursive = TRUE)
}