Monitoring, forecasting and best practices for

1
Monitoring, forecasting and best practices
for FLOOD Mitigation and prevEntion ACTION
3.2 Simulation of the flow in the Koiliaris
river basin using a combination of the HSPF model
and a Karstic model
George Karatzas, Nektarios Kourgialas Technical
University of Crete Department of Environmental
Engineering, Greece
2
STUDY OF AREA The Koiliaris River is located in
the Prefecture of Chania. The area of the
Koiliaris River basin has been calculated to be
about 130 km2

The aim of this presentation is the simulation of
the flow in the Koiliaris river basin using a
karstic model and a hydrology model

• GIS - (Arc View 9.2)
• Stochastic Karstic model
• BASIN HSPF

3
STUDY OF AREA AND HYDRO- METEOROLOGICAL NETWORK
Currently in the river basin 3 hydrometric and
3 meteorological stations are in place. Apart
from the meteorological station of Kalibes, which
is close to the river and the hydrometric station
of Agios Georgios that was installed in 2005, 2
extra telemetric hydrometric and 2 extra
telemetric meteorological stations have been
installed into the basin of Koiliaris
Agios Georgios
Kalibes
Samonas
Stylos
Psixro pigadi
Faraggi
4
GEOLOGY OF THE KOILIARIS RIVER BASIN
The main volume of water is discharged from the
karstic system of White Mountains (Lefka Ori)
through springs, streams and temporary
rivers The Stylos springs are considered the
major discharge points of the karstic system of
the area and one of the main water sources of the
Koiliaris River
5
STOCHASTIC MODELING OF THE KARSTIC SYSTEM
STOCHASIC KARSTIC MODEL OF MAILLET The
reason we chose Maillets model is that it has
physical meaning, it is based on the hydrologic
balance equation during the recession (no rain)
period and it assumes that the springs discharge
at specific points, (which is the case of Stylos
springs) The analysis above suggested the
existence of two reservoirs within the Karstic
system the upper reservoir with a faster
response and the lower reservoir with a slower
response A two part Maillet model was
developed representing the upper and lower
reservoirs
The model has the following formulation
Q (1-aLower)Qup QLower
Where Q is the total spring discharge, Qup and Q
Lower are the initial discharge contributions of
the upper and lower reservoirs respectively, QIN
is the initial discharge that enters in karstic
system, ?t is the time step equal to 1 day, a up
and a lower are the recession coefficients of the
upper and lower reservoirs
6
GENERAL THE HSPF MODEL
Advantages

• HSPF is one of the most complex hydrologic models

• It gives the possibility of simulation not only
  for the hydrology but also for the biogeochemical
  activities that take place in the river

• It takes into consideration the interaction with
  the sediment

• it is based on the environment of GIS and it can
  simulate better regions with intense topography

• it has an hourly step that is essential for
  regions where variables as the temperature and
  the humidity are presented in an hourly base

• HSPF is available without any financial cost
  from the EPA

• Extensive experience of simulation of flow by
  HSPF in America is already in hand, as well as,
  experience with regards to the possibilities, the
  advantages and the problems that the model
  presents by its application in the Mediterranean
  countries

7
Characteristics

• It separates the basin in permeable or not
  departments, in the river and in tanks,
• 1D simulation
• The flow is calculated with the equation of
  Chezy - Manning. It considers
• cross-correlation of surface flow with the depth
  of detention storage

The parameters of the river are defined by the
user and fixed in the Function Table (FTABLE)
Trapezoid cross-section of river and main
geometric parameters of this

• The hydrologic model of HSPF functions in the
  frame of BASINS

8
BASIN HSPF MODEL
BASIN 4
Input data inserted by GIS Land use , Digital
Elevation Model (DEM) Hydrographic network, Soil,
Geology
Watershed Delineation ? The Koiliaris river basin
is separated into 6 subbasins
1
2
3
For the HSPF simulation 3 subbasins have been
chosen
9
BASIN HSPF MODEL
Period of simulation The available data were
for the time period 09/01/2006 01/05/2007
WDM Util
The necessary meteorological data are ATEM
Hourly temperature DEWP Hourly dew point
temperature SOLR Hourly solar radiation WIND
Hourly wind speed PREC Hourly precipitation PEVT
Hourly potential evapotranspiration EVAP Hourly
evaporation Optional input data Observation
flow (for the calibration) Flow data from
springs (by karstic model)
10
BASIN HSPF MODEL
HSPF - run
This picture presents the environment of HSPF
and the 3 departments that have separated the
river with the corresponding uses of land per
subbasins
11
BASIN HSPF MODEL
The sub-model Scenario Generator (GenScn) where
the analysis of results of HSPF is taking place
The results of the hydrologic simulation are
presented in this environment where the
comparison between the observed field time series
and the model output data produces a statistical
analysis of the results
12
BASIN HSPF MODEL
HSPF - OUTPUT
The model simulation of the flow in subbasin 2
The model simulation of the flow in subbasin 3
13
BASIN HSPF MODEL
The model flow of the Koiliaris river at the
location Agios Georgios (subbasin1) and
comparison with the field data
14
THE NEXT STEP
The simulation of the Koiliaris river with HSPF
is on a preliminary stage and some parameters
have not yet been calibrated. An essential
problem that exists is that no field flow data
for all the subbasins or meteorological data for
the whole of the basin are available
However with the installation of the new
meteorological and hydrological stations, that
were presented earlier, the calibration of the
HSPF will become feasible
Thank you for your attention !