Riverbed Mapping with the Usage of Deterministic and Geo-Statistical Interpolation Methods: The Odra River Case Study

Anna Uciechowska-Grakowicz,Oscar Herrera-Granados

doi:10.3390/rs13214236

Abstract

In this contribution, interpolation methods were assessed to build the bathymetry of 200 km of the Odra River in South Poland. The River Bed Mapping (RBM) was carried out surveying the depth of several reaches of the canalized part of the river using an Global Navigation Satellite System (GNSS) with an echo sounder as well as two navigation schemes. The values from the interpolation were compared with the data from a classical cross-sectional survey as part of the ISOK (Polish acronym for Information System of Country Protection Against Extraordinary Hazards) project. Two statistical errors between the interpolation values and the ISOK information were estimated, namely, the Mean Absolute Error (MAE) and the Root Mean Square Error (RMSE). Thanks to the presented analysis, it was possible to compare and analyze which interpolation method fits the best for the batymetric surveying of a shallow river. For this specific case study, the TIN (Triangular Irregular Network) and the NN (Natural Neighbor) methods generates the most accurate RBM.

Highlights

Bathymetric data are essential for hydraulic numerical modeling and monitoring of sediment transport
We demonstrate the method of obtaining good quality bathymetry data with the use of accessible equipment such as a fish finder echosounder combined with RTK-Global Navigation Satellite System (GNSS) receiver, and compare several interpolation methods to choose those that are the most adequate for the object and data collection method
Six interpolation methods were used for the comparison of the River Bed Mapping (RBM)/Digital Bathymetric Modeling (DiBM) generation along the Odra Cascade, namely: Radial Basis Functions (RBF), Inverse Distance Weighted (IDW), TIN, Natural Neighbor (NN), ordinary Kriging (OK), and Spline

Summary

Introduction

Bathymetric data are essential for hydraulic numerical modeling and monitoring of sediment transport. Odra Cascade (from the barrage “Koźle” to the barrage “Malczyce”), which is 201.9 km long [1]. This model enabled hydraulic modeling and helped to identify areas with depth deficits in terms of inland navigation. It is an extensive task, which requires a method that can be time and cost effective, and that can provide accurate results, in less accessible areas, such as bays, narrow channels, groyne fields, as well as shallow waters terrains. We demonstrate the method of obtaining good quality bathymetry data with the use of accessible equipment such as a fish finder echosounder combined with RTK-GNSS receiver, and compare several interpolation methods to choose those that are the most adequate for the object (narrow, placid river) and data collection method (parallel to the riverbanks motorboat navigation)

Methods

Results

Discussion

Conclusion