get_nhdplus {nhdplusTools} | R Documentation |
Get National Hydrography Dataset V2 Subsets (Multirealization)
Description
Subsets NHDPlusV2 features by location (POINT), area (POLYGON), or set of COMIDs. Multi realizations are supported allowing you to query for flowlines, catchments, or outlets.
Usage
get_nhdplus(
AOI = NULL,
comid = NULL,
nwis = NULL,
realization = "flowline",
streamorder = NULL,
t_srs = NULL
)
Arguments
AOI |
sf (MULTI)POINT or (MULTI)POLYGON. An 'area of interest' can be provided as either a location (sf POINT) or area (sf POLYGON) in any Spatial Reference System. |
comid |
numeric or character. Search for NHD features by COMID(s) |
nwis |
numeric or character. Search for NHD features by collocated NWIS identifiers |
realization |
character. What realization to return. Default is flowline and options include: outlet, flowline, catchment, and all |
streamorder |
numeric or character. Only return NHD flowlines with a streamorder greater then or equal to this value for input value and higher. Only usable with AOI and flowline realizations. |
t_srs |
character (PROJ string or EPSG code) or numeric (EPSG code). A user specified - target -Spatial Reference System (SRS/CRS) for returned objects. Will default to the CRS of the input AOI if provided, and to 4326 for ID requests. |
Details
The returned object(s) will have the same
Spatial Reference System (SRS) as the input AOI. If a individual or set of
IDs are used to query, then the default geoserver CRS of EPSG:4326 is
preserved. In all cases, a user-defined SRS can be passed to t_srs
which will override all previous SRS (either input or default).
All buffer and distance operations are handled internally using in
EPSG:5070 Albers Equal Area projection
Value
sfc a single, or list, of simple feature objects
Examples
point <- sf::st_sfc(sf::st_point(c(-119.845, 34.4146)), crs = 4326)
get_nhdplus(point)
get_nhdplus(point, realization = "catchment")
get_nhdplus(point, realization = "all")
get_nhdplus(comid = 101)
get_nhdplus(nwis = c(11120000, 11120500))
area <- sf::st_as_sfc(sf::st_bbox(c(xmin = -119.8851, xmax =-119.8361,
ymax = 34.42439, ymin = 34.40473), crs = 4326))
get_nhdplus(area)
get_nhdplus(area, realization = "flowline", streamorder = 3)