fetchNHD: fetchNHD

In USEPA/TADA: EPA TADA (Tools for Automated Data Analysis) R Package

fetchNHD

Description

Fetches NHD features from either the high resolution or medium resolution version of the National Hydrography Dataset (NHD) that intersect catchments containing TADA Water Quality Portal observations.

Usage

fetchNHD(.data, resolution = "Hi", features = "catchments")

Arguments

.data	A dataframe created by TADA_DataRetrieval() or the geospatial equivalent made by TADA_MakeSpatial().
resolution	Whether to download the NHDPlus HiRes resolution ("Hi") or medium NHDPlus V2 resolution ("Med") version of the National Hydrography Dataset (NHD). Default is "Hi".
features	Which NHD features to return: "catchments", "flowlines", "waterbodies", or any combination.

Value

A list containing all selected NHD features associated with the WQP observations of interest. Or, if a single feature type is selected, a single geospatial object instead of a list. Default is "catchments" only.

See Also

TADA_DataRetrieval()

TADA_MakeSpatial()

Examples

## Not run: 
tada_data <- TADA_DataRetrieval(
  startDate = "1990-01-01",
  endDate = "1990-01-15",
  characteristicName = "pH",
  statecode = "CO",
  applyautoclean = TRUE,
  ask = FALSE
)

nhd_data <- fetchNHD(
  .data = tada_data, resolution = "Hi",
  features = c("catchments", "waterbodies", "flowlines")
)

## End(Not run)

USEPA/TADA documentation built on April 12, 2025, 1:47 p.m.