Modeling the Canal del Dique Complex

Overview

The Canal del Dique system in northern Colombia is an intricate network of a 115-km artificial navigation channel and dozens of interconnected wetlands (“ciénagas”). Its hydrology is influenced by both the Magdalena River and the tides of Cartagena Bay, creating a highly dynamic interplay of fluvial, tidal, and wetland processes.

To support a major systematization project aimed at improving environmental conditions, navigation, and flood safety, HCS developed a suite of large-scale numerical models capable of representing the full 870 km² system under current and future conditions. These models provided key technical input for engineering design and environmental management.

---

The Challenge

Designing and operating the proposed interventions required understanding a series of complex interactions:

• Narrow, fast canal flows vs. wide, slow wetland dynamics
• Seasonal hydrological variations and tidal forcing
• Bidirectional exchanges between wetlands and the canal
• Sediment transport threatening Cartagena Bay
• Ecological water requirements for multiple wetland systems
• Hydraulic performance of new control structures and channels

A predictive, validated modeling tool was needed to evaluate system behavior, quantify risks, and guide engineering decisions.

---

Our Contribution

HCS built an integrated set of numerical tools to address the full complexity of the system:

1. Regional 2D Hydrodynamic Model

• Implemented in TELEMAC-2D
• ~900,000 unstructured elements, with resolution from 5 m (channels) to 150 m (wetlands)
• Mixed fluvial–tidal boundary conditions
• Spatially variable Manning coefficients and wetland topography
• Calibration with water levels, velocities, and discharges across multiple hydrological conditions
• Validation under dynamic flood pulses and wetland filling events
• Executed using local, cloud, and clustered HPC resources

This model successfully captured the fast response of the canal and the slow, cumulative response of the wetlands, along with tidal interactions near the coast.

2. Environmental and Transport Modules

Extensions of the hydrodynamic model were used to analyze sediment transport and nutrient exchange patterns.

3. Coastal modeling

TELEMAC-3D models were implemented to study the coastal dynamics of sediments coming from the Canal del Dique complex.

4. CFD Modeling of Control Structures

Detailed 3D CFD simulations were performed to verify the hydraulic behavior of key engineered structures, supporting decisions on:

• Flow rating and energy dissipation
• Entrance geometry
• Navigation lock hydraulics
• Gate operation strategies

5. Operational Simulations

HCS tested various inflow regimes and gate-operation rules to assess:

• Flood safety for critical communities
• Wetland filling and emptying cycles
• Freshwater delivery targets
• Navigation water-level requirements

---

Figure 1: Calibration of the regional model based on point measurements

---

Key Findings

1. Flow exchanges between wetlands and the canal are strongly asymmetric

Upper wetlands fill from upstream flood pulses; lower wetlands respond mainly to tidal forcing and control structures.

2. Sediment transport is highly sensitive to tidal timing

Reversing currents modulate deposition patterns affecting wetlands and Cartagena Bay.

3. The canal responds rapidly, while wetlands respond slowly

This mismatch makes operating rules highly time-dependent.

4. Proposed interventions significantly reshape system hydraulics

The model quantified how channels, culverts, gates, and weirs alter flows, water levels, and wetland dynamics.

---

Engineering Applications Enabled by the Model

Safe Operation of the Calamar Structure

Extreme simulations established the maximum regulated inflow without exceeding critical water levels.

Design Levels for the Puerto Badel Structure

The model determined maximum and minimum retained water levels under extreme flood and drought scenarios.

Wetland Connectivity Design

The model supported the design of channels, culverts, dikes, and overflow structures to improve ecological flows and reduce flood risks.

CFD Verification

3D CFD analyses validated the detailed hydraulic behavior of the main regulating structure.

---

Conclusion

This project demonstrates the capability of HCS to build and operate large-scale, high-resolution hydrodynamic models that integrate fluvial, tidal, wetland, and infrastructural processes. The tools developed for Canal del Dique provided essential guidance for engineering design, environmental planning, and operational decision-making in one of Colombia’s most important water systems.

HCS offers this expertise to international clients seeking advanced hydrodynamic modeling, management analysis for complex systems, and CFD-aided design verification for hydraulic infrastructure.