DOI: 10.5066/p14f2le9
title: Field measurements of water depth and remotely sensed data from the Mulchatna River, Alaska, collected July 12-August 14, 2024

description: This data release provides field measurements of water depth and aerial and satellite images from the Mulchatna River in Alaska. These data were used to assess the feasibility of mapping the bathymetry of this remote, proglacial river, located in Lake Clark National Park and Preserve, using several depth retrieval algorithms. This approach could facilitate geomorphic and habitat monitoring by agencies tasked with managing remote, hard to access landscapes, like the National Park Service. This project is a collaboration between the National Park Service's Water Resources Division and Alaska Regional Office and the USGS Observing Systems Division.
Please refer to the "Entity and attribute" and "Process step" sections of the metadata for further detail regarding these files and how they were produced, but the following is a brief summary of the contents of this data release. The NAD_1983_2011_StatePlane_Alaska_5_FIPS_5005 projected coordinate system is used throughout and the coordinates and depths have units of meters.

The file MulchatnaDepthFieldData.csv contains field measurements of water depth, with columns for easting and northing spatial coordinates and depths.
The files MulchatnaXS1adcp.zip and MulchatnaXS2adcp.zip contain acoustic Doppler current profiler (ADCP) data from two cross sections where discharge measurements were made. Each zip folder contains MATLAB *.mat files that were exported from the SonTek RSQ software package, with a separate *.mat file for each of four passes across the channel. In addition, the output *.mat files produced by the QRev software (described in the Process Step section of the metadata) with calculated discharges and uncertainties are also included in the two zip folders. Please note that these discharge measurements were not made in accordance with standard USGS protocols and did not include compass calibrations, system checks, or temperature checks and assumed that the edges of the channel closer to the banks than the end of each ADCP transect made no contribution to the total discharge.
The file ReachMasks.zip contains channel masks created by digitizing polygons on the orthomosaic derived from the aerial imagery. The polygons were saved as individual shapefiles for the full study area and for each of the three reaches.
The file WVgeorefSubsets.zip contains geo-referenced WorldView2 satellite image subsets for the full study area and for each of the three reaches, saved as ENVI *.dat files with associated header (*.hdr) files.
The file MulchDSMsub.tif is a digital surface model (DSM) derived from aerial imagery acquired by the National Park Service and processed using a structure-from-motion workflow, saved in a GeoTIFF format. Note that this DSM is not referenced to an established vertical coordinate system and elevations within the DSM are only accurate relative to one another. These data were only used for estimating local channel slopes and should not be used as absolute elevations for other purposes.
The file MulchSubMos.tif is an orthomosaic derived from aerial imagery acquired by the National Park Service and processed using a structure-from-motion workflow, saved in a GeoTIFF format.

Users are advised to thoroughly read the metadata file associated with this data release to understand the appropriate use and limitations of the data provided herein.

Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.
Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. MAXAR retains the copyright on all the images: "© 2024 MAXAR".