Multi-algorithm reinforcement learning framework with feedforward networks for resilient water tank scheduling systems

Efficient and resilient control of water distribution systems (WDS) is critical for sustainable infrastructure management under increasingly uncertain demand conditions. This study presents a comprehensive benchmarking and sensitivity analysis of three reinforcement learning algorithms-Proximal Policy Optimization (PPO), Deep Q-Network (DQN), and Asynchronous Advantage Actor-Critic (A3C)-for water tank scheduling across multi-day planning horizons. Our simulation-based framework incorporates realistic demand variability, extreme operational scenarios, and temporal modeling using LSTM networks to enable robust agent training. Extensive evaluation reveals that PPO achieves superior performance in long-horizon scenarios with up to 40% fewer pump activations and 25% fewer safety violations than DQN, while maintaining competitive performance across shorter horizons. A detailed sensitivity analysis identifies learning rate as the most critical hyperparameter, with DQN showing narrow optimal ranges (1× 10⁻³) compared to PPO’s broader robustness (1× 10⁻⁵ to 3× 10⁻⁴). The ablation study demonstrates that while LSTM networks enhance temporal modeling, the simpler DQN-FFN architecture notably outperforms LSTM-augmented counterparts, achieving superior cumulative rewards (−93.85 vs −134.15 for PPO-LSTM). Under extreme demand noise up to ±50 units, PPO demonstrates exceptional robustness with only 12% performance degradation compared to 28% for DQN. The study provides practical guidelines for algorithm selection, hyperparameter tuning, and action-space design, establishing a foundation for transparent AI-driven control in complex WDS and directly implicating Industry 4.0/5.0 infrastructure modernization.