Project Background and Objectives

Longgang (LG) District covers 388 km2 of undulating areas in northeastern Shenzhen. It is a well-developed mixed industrial, commercial, and residential urban area with a population of 4.78 million. The Longgang District Water Bureau aims to enhance water management with the Smart Water Management System by integrating information resources and online modeling services. This system provides evaluation results for various water systems, including reservoir operations, flood forecasting, and wastewater operations to minimize combined sewer overflows (CSOs).

Ewaters, as a sub-consultant to the project team formed with the China Institute of Water Resources and Hydropower, HUAWEI, and Power Group China, is responsible for model development, calibration, and the creation of a real-time forecasting and early warning system. Services included:

Model Build

·   Developed 3 river catchment 1D-2D coupled flood models, covering 39 operational reservoirs and 62 river reaches within the entire area.

·   Created 3 river hydrodynamic (HD) and water quality (WQ) models.

·   Built five urban stormwater and wastewater network models.

·   Offline models were initially built and calibrated, then embedded into Delft-FEWS for real-time simulation and forecasting.

Development of Real-Time Forecasting System

·    Utilized the Delft-FEWS Platform 2022 to develop the real-time forecasting system.

·  Integrated data from approximately 35 rain gauges and 450 water level and quality monitoring stations. The data was designed to be automatically processed and connected to the models for generating forecast runs.

·    The system executes sequences and parallel processes based on an optimized design, producing forecast results and reports quickly.

·   Operational for nine months, the system provides twice-daily forecasts for river and drainage network levels, flow rates, and river water quality for the next 24 hours within about 15 minutes. It also forecasts reservoir levels and flow for the next 72 hours in approximately 3 minutes.

·    Additionally, the system generates hourly rolling forecasts to predict water depth in flood-prone areas for the next 3 hours, completing these in about 6 minutes.

·   The system operates automatically without requiring operator intervention, also providing continuous and reliable forecasting through web services.

Service Delivery and Timeline

The modeling and development of the forecasting system were implemented in four phases:

·   Phase 1: Ewaters conducted a detailed investigation of the data, management, and needs of various stakeholders. An assessment report was produced to confirm project understanding, requirements, expectations, and a detailed work plan.

·   Phase 2: Offline models were developed, well-calibrated, and submitted.

·   Phase 3: Delft-FEWS was applied to develop the complex operational forecasting system to suit multi-sectoral needs.

·  Phase 4: System installation, testing, validation, training, and delivery of reports were completed. The delivered system achieved objectives and client approval in December 2023.

Currently, the project is in the warranty phase to further calibrate the models and optimize system performance.

Figure 2  River water level forecasting map display. Hydrographs available at a click