---
OA_place: publisher
OA_type: free access
_id: '22523'
abstract:
- lang: eng
  text: 'In hydrological models, variably saturated flow is often described using
    the Richards equation, either in a fully three-dimensional (3D) implementation
    or using a quasi-3D framework based on the 1D Richards equation for vertical flow
    and a flow-approximation for the other two dimensions. However, it is unclear
    in which configuration or under which boundary conditions these approximations
    can produce adequate estimates. In this study, two formulations with a quasi-3D
    approach are benchmarked against a fully 3D model (HYDRUS-3D). The formulations
    are: the Real-time Integrated Basin Simulator + VEGetation Generator for Interactive
    Evolution (tRIBS + VEGGIE) model that uses the Dupuit–Forchheimer assumption and
    the Tethys & Chloris (T&C) model that implements the kinematic approach.
    Effects of domain slope, hillslope size, event size and initial moisture conditions
    on simulated runoff and soil moisture dynamics are examined in event-based simulations
    at the hillslope scale. The Dupuit–Forchheimer assumption (tRIBS-VEGGIE) produces
    deviations from the HYDRUS-3D solutions only for simulations with initially dry
    soil. Using the kinematic approach (T&C) results in deviations from the 3D
    solution primarily for the small hillslope domain in combination with a gentle
    slope angle. This applies especially to the partition between subsurface and surface
    runoff production, with T&C being biased towards the latter. For all other
    cases investigated, the simpler formulations provide reasonable approximations
    of the 3D model.'
article_processing_charge: No
article_type: original
author:
- first_name: Luisa
  full_name: Hopp, Luisa
  last_name: Hopp
- first_name: Simone
  full_name: Fatichi, Simone
  id: cf8e546b-a9b0-11f0-a43b-aa89ed1b56d6
  last_name: Fatichi
- first_name: Valeriy Y.
  full_name: Ivanov, Valeriy Y.
  last_name: Ivanov
citation:
  ama: 'Hopp L, Fatichi S, Ivanov VY. Simulating water flow in variably saturated
    soils: A comparison of a 3D model with approximation-based formulations. <i>Hydrology
    Research</i>. 2016;47(2):274-290. doi:<a href="https://doi.org/10.2166/nh.2015.126">10.2166/nh.2015.126</a>'
  apa: 'Hopp, L., Fatichi, S., &#38; Ivanov, V. Y. (2016). Simulating water flow in
    variably saturated soils: A comparison of a 3D model with approximation-based
    formulations. <i>Hydrology Research</i>. IWA Publishing. <a href="https://doi.org/10.2166/nh.2015.126">https://doi.org/10.2166/nh.2015.126</a>'
  chicago: 'Hopp, Luisa, Simone Fatichi, and Valeriy Y. Ivanov. “Simulating Water
    Flow in Variably Saturated Soils: A Comparison of a 3D Model with Approximation-Based
    Formulations.” <i>Hydrology Research</i>. IWA Publishing, 2016. <a href="https://doi.org/10.2166/nh.2015.126">https://doi.org/10.2166/nh.2015.126</a>.'
  ieee: 'L. Hopp, S. Fatichi, and V. Y. Ivanov, “Simulating water flow in variably
    saturated soils: A comparison of a 3D model with approximation-based formulations,”
    <i>Hydrology Research</i>, vol. 47, no. 2. IWA Publishing, pp. 274–290, 2016.'
  ista: 'Hopp L, Fatichi S, Ivanov VY. 2016. Simulating water flow in variably saturated
    soils: A comparison of a 3D model with approximation-based formulations. Hydrology
    Research. 47(2), 274–290.'
  mla: 'Hopp, Luisa, et al. “Simulating Water Flow in Variably Saturated Soils: A
    Comparison of a 3D Model with Approximation-Based Formulations.” <i>Hydrology
    Research</i>, vol. 47, no. 2, IWA Publishing, 2016, pp. 274–90, doi:<a href="https://doi.org/10.2166/nh.2015.126">10.2166/nh.2015.126</a>.'
  short: L. Hopp, S. Fatichi, V.Y. Ivanov, Hydrology Research 47 (2016) 274–290.
das_tickbox: '1'
date_created: 2026-07-27T12:30:24Z
date_published: 2016-04-01T00:00:00Z
date_updated: 2026-08-06T08:05:42Z
day: '01'
doi: 10.2166/nh.2015.126
extern: '1'
intvolume: '        47'
issue: '2'
keyword:
- hillslope hydrology
- hydrologic modeling
- parsimonious approximation
- surface-subsurface hydrology
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://doi.org/10.2166/nh.2015.126
month: '04'
oa: 1
oa_version: Published Version
page: 274-290
publication: Hydrology Research
publication_identifier:
  eissn:
  - 2224-7955
  issn:
  - 1998-9563
publication_status: published
publisher: IWA Publishing
quality_controlled: '1'
scopus_import: '1'
status: public
title: 'Simulating water flow in variably saturated soils: A comparison of a 3D model
  with approximation-based formulations'
type: journal_article
user_id: 2DF688A6-F248-11E8-B48F-1D18A9856A87
volume: 47
year: '2016'
...