Hydrological Model Continuum (HMC)

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🌍 Overview

The Hydrological Model Continuum (HMC) is a distributed hydrological model developed by the CIMA Research Foundation.

It is operationally used by the Italian Civil Protection Department (DPC) and international partners.

HMC is the computational core of the Flood-PROOFS modelling system, designed to support:

• flood forecasting and nowcasting
• hydrogeological risk prevention
• water resource management
• environmental and climate simulations

The system is operational in:

• Italy
• Bolivia
• Albania
• Lebanon

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🚀 Version

• Current version: v3.4.2
• Release date: 2026-04-09

👉 See CHANGELOG.md

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⚙️ Main Features

• Distributed hydrological simulation
• Routing modes (v3.4.0):
  • Grid (iFlagRoutingType = 1)
  • Indexed (iFlagRoutingType = 2)
• Surface and subsurface flow
• Snow model and energy balance
• Soil moisture and groundwater dynamics
• Channel network and convolution schemes
• NetCDF input/output support
• High-performance Fortran implementation

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🧩 Model Components

• Modified Horton infiltration method
• Runoff routing
• Subsurface flow routing
• Energy balance (Force-Restore equation)
• Deep soil temperature filter (Tdeep)
• Water table and deep flow routing
• Snow model and corrections
• Soil moisture correction
• Groundwater fracturation

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🖥️ Requirements

System

• Linux (Debian/Ubuntu recommended)
• 64-bit architecture

Compiler

• Fortran 2008+ (GFortran ≥ 8 recommended)

Libraries

• NetCDF4
• HDF5
• Zlib

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📦 Installation

1. Install dependencies

git clone https://github.com/c-hydro/fp-env
cd fp-env
bash setup_fp_env_system.sh
source $HOME/fp_libs_system/fp_env_system

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2. Compile HMC

Automatic mode (recommended)

./configure.sh hmc-dev $HOME/fp_libs_system $HOME/fp_libs_system/hmc true

Default mode

./configure.sh

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⚙️ Compilation configuration

Recommended settings:

• Compiler: GNU/GFortran
• Optimization: Production
• NetCDF: enabled
• Profiling: disabled

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3. Build output

Executable will be created in:

$HOME/fp_libs_system/hmc/

Example:

HMC_Model_V3_Exec.x

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▶️ Run Model

HMC uses a simplified interface:

HMC.x {domain}.info.txt

Example

./HMC_Model_V3_Exec.x po.info_run_et.txt

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📊 Profiling

Compile profiling version

RUN=Profile ./configure.sh

Run profiler

./HMC_Tools_Profiler.sh HMC_Model_V3_Profile.x domain.info.txt

Outputs

• hmc_model_analysis.txt
• hmc_model_analysis.png

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🧠 Memory Analysis

Valgrind (memcheck)

./HMC_Tools_Memory.sh HMC_Model_V3_Exec.x domain.info.txt

Callgrind

valgrind --tool=callgrind ./HMC_Model_V3_Exec.x domain.info.txt

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📁 Input / Output

Input

• {domain}.info.txt (namelist configuration)
• NetCDF forcing datasets
• Static maps (DEM, soil, vegetation, etc.)

Output

• NetCDF datasets
• Time series
• Diagnostic variables

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🧪 Development

Recommended IDEs

• VS Code
• NetBeans
• Code::Blocks

Debugging tools

• gdb
• valgrind
• gprof

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⚙️ Continuous Integration

GitHub Actions automatically:

• builds HMC
• checks compilation
• produces executable artifacts

Workflow:

.github/workflows/build.yml

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🤝 Contributing

1. Fork repository
2. Clone with submodules

   git clone --recursive

3. Create a feature branch
4. Add code and tests
5. Submit a Pull Request

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👨‍💻 Authors

See 👉 AUTHORS.md

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📜 License

Licensed under the European Union Public Licence (EUPL v1.2)

👉 See LICENSE.rst

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📖 Citation

If you use HMC:

Delogu, F., Gabellani, S., Silvestro, F., Libertino, A., Ercolani, G. (2026)
Hydrological Model Continuum (HMC) v3.4.0
CIMA Research Foundation

BibTeX

@software{hmc_v340,
  title = {Hydrological Model Continuum (HMC)},
  version = {3.4.0},
  author = {
    Delogu, Fabio and
    Gabellani, Simone and
    Silvestro, Francesco and
    Libertino, Andrea and
    Ercolani, Giulia
  },
  year = {2026},
  publisher = {CIMA Research Foundation},
  url = {https://github.com/c-hydro/hmc-dev}
}

👉 Machine-readable citation: CITATION.cff

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🔗 References

• https://www.cimafoundation.org/
• https://github.com/c-hydro/hmc-dev
• https://github.com/c-hydro/fp-env
• https://fortran-lang.org/

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🧠 Topics

Hydrology · Hydrological Model · Flood Forecasting · Fortran · NetCDF · HPC · Environmental Modeling

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Hydrological Model Continuum — Scientific Modeling for Water Systems