Model Library

QUAL2Kw

Model name: QUAl2Kw (QUAL2Kw)

Developed by: Pelletier et al. (2006) (Last update: 2016)

Model type: 1D, steady-state/non-steady-state, process-based, hydraulics, hydrological and water quality, waterbody model

History: QUAL2Kw is an improved version of QUAL2K.

Computational requirements: Windows 98 or higher, Microsoft Excel is required for graphical user interface.

Software requirements: GIS: optional.

Link to download model

Capabilities and Limitations:

Capabilities

  • It uses Genetic Algorithm (GA) for auto-calibration and parameters optimization;
  • User-friendly interface;
  • It accounts for diurnal fluctuations in temperature and dissolved oxygen (Mohamad Noor et al., 2024);
  • The sediment-water fluxes of dissolved oxygen and nutrients are modeled internally instead of being predefined (Pelletier et al., 2006);
  • It models hyporheic zone (Pelletier et al., 2006);
  • The model converts algal death to carbonaceous biochemical oxygen demand, making it suitable for systems with significant macrophyte interactions (Kannel et al., 2011).

Limitations

  • It only simulates the main stem of a river, excluding branches (Kannel et al., 2011);
  • The model does not incorporate an uncertainty component (Kannel et al., 2011);
  • It is a one-dimensional, mainly steady-flow model (Kannel et al., 2011);
  • It cannot handle variable flow conditions (Kannel et al., 2011).

Model Inputs and Outputs:

Inputs

Location, Date, Boundary conditions, Hydraulic features, Meteorological data, Parameters for water quality kinetics rates and constants, Optional parameters to navigate genetic algorithm for automated calibration.

Outputs

Time-series simulation of water quality parameters. The model simulates the transport and fate of various constituents, including temperature, biochemical oxygen demand, dissolved oxygen, phytoplankton, nitrogen, phosphorus, pH, alkalinity, inorganic suspended solids, pathogenic bacteria, and bottom algae.

Example:

Reference

Angello, Z. A., Behailu, B. M., & Tränckner, J. (2021). Selection of optimum pollution load reduction and water quality improvement approaches using scenario-based water quality modeling in Little Akaki River, Ethiopia. Water, 13(5), 584. https://doi.org/10.3390/w13050584

Objective

The objectives of this research were to simulate pollutant transport and dynamics using a modified stream water quality model (QUAL2Kw) in the LAR, to develop a scenario-based water quality management strategy and ultimately select the optimal water quality improvement and pollutant load reduction approaches in the study area.