queryFlowlines: Download NHDPlus flow lines
In BiomarkABS/PITcleanr: Cleans up PIT tag capture histories

queryFlowlines

R Documentation

Download NHDPlus flow lines

Description

Download a subset of the NHDPlus v2.1 flowlines that covers a list of detection sites.

Usage

queryFlowlines(
  sites_sf = NULL,
  root_site_code = NULL,
  min_strm_order = 0,
  max_upstream_comid = NULL,
  combine_up_down = TRUE
)

Arguments

`sites_sf`	An 'sf' class object containing points of all detection sites. Must contain a column named 'site_code' containing the site code of each site.
`root_site_code`	Site code for the starting detection site.
`min_strm_order`	minimum stream order to query flowlines for. Default value is '0'.
`max_upstream_comid`	if provided, this function will filter out any flowlines upstream of this unique identifier (COMID) in the NHDPlus stream network. Default value is 'NULL'. For assistance identifying a COMID, please see the 'nhdplusTools' package, specifically the 'discover_nhdplus_id()' function.
`combine_up_down`	Should the flowlines upstream and downstream of the starting point ('root_site_code') be combined into a single object, or be returned as separate elements? The default value is 'TRUE'

Value

list with at least two elements: 'flowlines' is the 'sf' object of flowlines downloaded from NHDPlus. 'basin' is the polygon representing the catchment upstream of the root site. If 'combine_up_down' is 'FALSE', there is a third element in the list, called 'dwn_flowlines', containing an 'sf' object of flowlines downstream of the root site.