Prediction of the river water environment carrying capacity using LSTM networks

Abstract

River basins receive wastewater from socio-economic activities. In such a context, a comprehensive assessment and forecast of load-bearing capacity needs to be developed. This capacity depends on many complex factors, such as hydrology, hydraulics, and environment, leading to applying a modelling approach. This study aims to propose a hybrid modelling approach to evaluate and predict the river water environmental capacity (RWEC) in a basin. Big data technology with Python is applied to process modelling results and RWEC forecasts. The long short-term memory (LSTM) model predicts RWEC on each reach of the river channel network. The {RWECP, i, P = Nitrate, BOD, Phosphate, i = hourly} data set and related factors form a time series of data used for the LSTM forecasting model. Forecast results are evaluated through the root mean square error (RMSE) and mean absolute error (MAE). The results show that the average level over all 24 reaches for 7 forecast days: RMSENitrate = 22.16 (kg/day), RMSEBOD = 38.92 (kg/day), and RMSEPhosphate = 0.79 (kg/day). This is an acceptable result for a complex system and 7-day forecast. The results of the study help significantly with pollution control. HIGHLIGHTS Suggesting steps to determine river water environmental capacity (RWEC).; Building a forecasting model based on long short-term memory (LSTM) to predict RWEC.; Assessing and forecasting RWEC for the concrete basin.; Comparing forecast accuracy by standard metric RMSE and MAE.; Clarifying RWEC dependence on hydrodynamic and environmental factors.;

Keywords

• eco-hydrodynamic
• hydrological models
• lstm
• river water environmental capacity
• water quality