The Amur River flood of 2013: analysis of genesis, frequency assessment, and modeling results
Abstract
The 2013 Amur River flood was one of the most significant and damaging natural disaster ever
to hit Russia. During July-September of 2013, almost the whole basin of the Amur River, the tenth
largest river basin in the world, was stricken by unprecedentedly powerful and protracted flooding. The
magnitude of this flood event was extraordinary: extreme water levels were registered at the streamflow
gauges along the main river and its tributaries; within the largest cities (Khabarovsk, Komsomolsk-onAmur) the Amur River reached the record stage, 1.5-2 meters surpassing the previous records for tens
years of observations. In the Russian part of the basin, damages approached $1.3 billion.
In our study, two main causes of the Amur flood of 2013 have been analysed as follows: (1) the
unique atmospheric situation, which was characterised by formation of the strong extratropical blocking
pattern over north-west of the Pacific Ocean during the monsoon season, and resulted in anomalously
heavy and prolonged rain events over the basin; and (2) cold, snowy winter of 2012-2013 and late
snowmelt season of 2013 lead to saturation of soils over the vast territory just before the heavy rains.
The main observed characteristics of flood have been summarized and an attempt has been carried out
to assess frequency of the extreme flood peak discharge registered in the Khabarovsk city in August
2013. It has been shown that there is a large uncertainty in statistical assessment of the observed flood
hazard: the recurrence interval of the extreme discharge varies from 100 to 300 years depending on the
probability distribution curve fitting the available discharge observation data.
The physically-based semi-distributed model of runoff generation in the Amur River basin has
been developed and applied for reproducing the flood of 2013. The model is based on the ECOMAG
modelling system and describes processes of snow accumulation and melt, soil freezing and thawing,
water infiltration into unfrozen and frozen soil, evapotranspiration, thermal and water regime of soil,
overland and subsurface flow. To simulate channel flow a hydrodynamic MIKE-11 model was coupled
with the ECOMAG. The model was applied for the middle part of the Amur River including two largest
left tributaries, Zeya and Bureya Rivers, where large reservoirs are located. The model was calibrated
using streamflow discharges measured in the different gauges of the main river and its tributaries for 10
years (2000-2009). Validation of the model was carried out for the period of 2010-2013. For the flood of
2013, the Nash and Sutcliffe efficiency criterion of the river stage simulation has been obtained as 0.840.94 depending on the streamflow gauge.
Numerical experiments have been carried out to assess the effect of the Zeya reservoir
regulation on the middle Amur River stage. It has been shown that in the absence of the reservoir, the
water levels within the Blagoveshchensk city (downstream of the Zeya River mouth) would be 0.5-1.5 m
higher than the levels measured during the flood of 2013.
Study basin
Near the largest cities, the river stage
exceeded the maximal one recorded during
the period of instrumental observations
Water Problem Institute, Russian Academy of Sciences, Moscow, Russia
e-mail: hydrowpi@aqua.laser.ru
Modeling results
The ECOMAG calibration (2000-2009)
Hydrographs of the water inflow into the Zeya
The ECOMAG validation (2010-2013)
reservoir
Study Area
On the limitations of the standard flood
frequency analysis of the Amur streamflow data
Annual maximum flood peak discharge:
Amur River at the Khabarovsk city
92 years of observations including maximal
discharge of Sept. 8, 2013
50000
m3/s
46000 м3/с
Calibration of the channel flow sub-model
(MIKE-11) against the river stage measured at
The recurrence interval of the different gauges of the Amur River (1975-1986)
45000
40000
35000
30000
Validation of the channel flow sub-model
(MIKE-11) against the river stage measured at
different gauges of the Amur River(1994-2008)
Modeling the river stage at the
different gauges of the Amur
River (01/05/2013 – 30/09/2013)
maximal discharge of 46000 m3/s
(Sept. 08, 2013) estimated using
Kritsky⎯Menkel distribution
is
270 years, while that derived
from the Log-Pearson type III
distribution is 100 years.
25000
20000
15000
10000
5000
0
1895
90000
The extreme flood that formed in the Amur
River basin in July ⎯ September 2013
embraced vast territories in the Russian Far
East and Northeastern China and became
one of the major natural disaster of the XXI
century in terms of duration, the area
involved, the number of persons affected,
and the economic losses. Almost the entire
Amur Basin, which ranks tenth in the world
in the area (1.85 million km2), suffered
from a disastrous flood
The Russian part of the basin
 The total damage is at least USD 1.3 billion
 The total number of persons affected
by the flood was in excess of 168000
 More than 12000 houses were destroyed
and almost 20% of them are beyond rebuilding
A. Gelfan, Yu. Motovilov, A. Kalugin
1914
1933
1952
1971
1990
m3/s
80000
Log-Pearson III
distribution
70000
Observed annual
maximum flood
peak discharges
60000
50000
40000
30000
20000
Kritsky-Menkel
distribution
10000
0
0.0001
The Chinese part of the basin (much more populated)
 The total damage is at least 5.3 USD billion
 There had been 85 deaths, and 105 people are
missing (Sept., 2013)
 At least 306,000 homes and structures were
damaged or destroyed
0.001
0.01
0.1
1 %
Physically based modeling of runoff generation in the Amur River basin
Semi-distributed physically based model ECOMAG (Motovilov)
(Ecological Model for Applied Geophysics)
Vertical structure of ECOMAG
Simulated hydrographs at the Zeya River mouth (ECOMAG)
The major problems that one
faces when trying to apply a
standard FFA for estimating
the recurrence interval of the
extreme flood of 2013 is the
lack of daily discharge data.
Presently, as little as two
streamflow gages (Khabarovsk
and Bogorodskoe) are in
operation on the 2824 km
Amur River.
Hydrograph is calculated
under the assumption of
absence of the Zeya reservoir
regulation capacity (2)
Base GIS information
Digital elevation model
Simulation
Genesis of the flood
The main factor is the unique synoptic situation
characterised by the following main features:
1) the formation of a high frontal zone, along which deep
cyclones moved incessantly during two months
2) the formation of a blocking high pressure domain
above the northwestern Pacific, which hampered a
displacement
of those cyclones from the continent toward the Sea of
Okhotsk
Another critical factor of the Amur flood is the high
water saturation of soils in the vast areas of river basins
by the beginning of flood season. High moisture content
of soils was a result of the cold snowy winter of
2012⎯2013 and a late spring, during which a considerable
portion of snowmelt water was absorbed by soils. The
saturation of soils has led to a critical drop in their water
retention capacity and an abrupt decrease in the natural
regulating capacity of river basins before the rains.
Numerical experiments on the effect of the Zeya reservoir on flood mitigation
Soil
Discharges in river network
Vegetation
Layer of runoff
Hydrograph is
calculated under the
reservoir regulation (1)
Modeling the river stage at the different
gauges of the Amur River (MIKE-11)
Hydrographs
Modelled area
Data base
GIS - analysis of simulated results
Climate
Layer of runoff
Soil moisture
Pollution
Evapotranspiration
Vegetation
Soil
Examples of ECOMAG applications
The absence of the regulating capacity of the reservoir
would cause an increase in water level on the rise of
flood wave (7 August) by 1.5 m at Blagoveshchensk
and Grodekovo gages, by 1.1 m at Konstantinovka
and Poyarkovo gages, and by 1.4 m at Innokent’evka
gage , but at flood peak in the Amur (from 20 to 21
August) would cause an increase in water level by
0.45 m at Blagoveshchensk and Grodekovo gages, by
0.35 m at Konstantinovka gage, by 0.4 m at Poyarkovo
gage, and by 0.5 m at Innokent'evka gage.
Conclusions
1. Estimates of the extreme flood frequency obtained from the available scarce data in the Amur
River basin are uncertain and information is needed additional to that extracted from the data.
The additional information can be obtained from the results of the extreme flood modeling.
2. The model has been developed based on the ECOMAG model of runoff generation coupled
with the MIKE-11 model of channel flow. The model has allowed us representing hydrological
processes resulted in the extreme flood generation.
3. Numerical experiments have been carried out to assess the effect of the Zeya reservoir
regulation on the middle Amur River stage. It has been shown that in the absence of the reservoir
regulation capacity, peak water levels within the Blagoveshchensk city (downstream of the Zeya
River mouth) would be 0.5-1.5 m higher than the levels measured during the flood of 2013.