Stream morphology map (DP4.00131.001)

Geomorphology surveys encapsulate the entirety of the aquatic reach, which at most NEON sites is equivalent to approximately 1,000 meters in stream length. A raw survey data file includes each of the individually mapped points collected by the total station during the geomorphology survey. Each point contains a Northing, Easting, and elevation coordinate relative to fixed benchmarks that are typically installed near the staff gauge and discharge cross-section (where most surveys begin). Mapped points are distributed at a high resolution (typically less than 1m) throughout the extent of the aquatic reach. Points are mapped along the main channel to capture thalweg (or the deepest part of the stream) elevation, along the edge of water to capture wetted width, and along select transects that run perpendicular to the channel in order to capture cross-sectional area. Additional points are collected at stream features that locally influence fluvial processes (i.e. large woody debris jams, mid-channel bars, etc.). Northing, Easting, and elevation data contained in raw survey files are relative to a local Cartesian coordinate plane (X, Y, and Z, respectively) defined by the fixed benchmark used to orient the total station at the beginning of the survey. Fixed benchmark locations are globally referenced (WGS 84 reference coordinate system) and locally projected (UTM Zone xNorth) using global positioning instrumentation to an accuracy of 10-30 centimeters of elevation. The degree of additional uncertainty associated with each survey will vary and is dependent on operator error, site-specific conditions, and environmental factors. Uncertainty associated with each survey is included within the data product package. During post-processing, GPS data is utilized to convert Northing and Easting values to latitude and longitude and elevation values to meters above mean sea level. All geo-referenced survey data is considered Level 4. Geomorphology surveys are conducted a minimum of once every five years. During years when there is not a geomorphology survey, a geo-referenced rapid habitat assessment is conducted throughout the monitoring reach that includes a large woody debris survey, pebble count surveys at the same transects that are sampled during geomorphology surveys, and delineated aquatic habitat units. Instrumentation: Hilti POS 180 robotic total station