Development of Deep Learning Models to Improve the Accuracy of Water Levels Time Series Prediction through Multivariate Hydrological Data

Since predicting rapidly fluctuating water levels is very important in water resource engineering, Long Short-Term Memory (LSTM) and Gated Recurrent Unit (GRU) were used to evaluate water-level-prediction accuracy at Hangang Bridge Station in Han River, South Korea, where seasonal fluctuations were large and rapidly changing water levels were observed. The hydrological data input to each model were collected from the Water Resources Management Information System (WAMIS) at the Hangang Bridge Station, and the meteorological data were provided by the Seoul Observatory of the Meteorological Administration. For high-accuracy high-water-level prediction, the correlation between water level and collected hydrological and meteorological data was analyzed and input into the models to determine the priority of the data to be trained. Multivariate input data were created by combining daily flow rate (DFR), daily vapor pressure (DVP), daily dew-point temperature (DDPT), and 1-hour-max precipitation (1HP) data, which are highly correlated with the water level. It was possible to predict improved high water levels through the training of multivariate input data of LSTM and GRU. In the prediction of water-level data with rapid temporal fluctuations in the Hangang Bridge Station, the accuracy of GRU's predicted water-level data was much better in most multivariate training than that of LSTM. When multivariate training data with a large correlation with the water level were used by the GRU, the prediction results with higher accuracy (R-2=0.7480-0.8318; NSE=0.7524-0.7965; MRPE=0.0807-0.0895) were obtained than those of water-level prediction results by univariate training.

Automated summary

In this study, LSTM and GRU models were used to evaluate the accuracy of water-level prediction at Hangang Bridge Station, South Korea, with a focus on rapidly fluctuating water levels. By analyzing the correlation between water level and collected hydrological and meteorological data and training with multivariate input data, improved predictions of high water levels were achieved. GRU demonstrated better accuracy in predicting water levels with rapid temporal fluctuations, especially when using multivariate training data highly correlated with the water level.