4. Cambodia 2006 Country Report
4.1 General situation
In Cambodia conditions during the 2006 flood season were
below average both in terms of peak and volume. The flood
peak was, in fact, amongst the lowest recorded over the last
80 or more years. The maximum discharge for the year occurred
in mid August, after which water levels decreased considerably
until early October and the passage across the region of Severe
Tropical Storm Xangsane. This weather system generated a slightly
lower second peak in mid October, an uncommon feature of the
annual hydrograph. As a result of these below normal seasonal
flows no significant crop losses were reported, with the exception
of the fact that the unseasonally late second peak led to
the inundation of some low lying areas. Some early flood recession
rice plantings were lost and a second replanting was required.
No flood damage to infrastructure was recorded for the year.
4.2 Lessons learnt from a field trip to
Kampong Cham, Kratie and Stung Treng—24th to 26th October
2006
- Kampong Cham: The major flood related issues here are
river bank erosion, the regular loss of crops and damage
to property, domestic and commercial disruption, low levels
of social awareness of the flood hazard, inadequate institutional
capacity to receive and disseminate flood warnings and inadequate
investment in flood mitigation and rehabilitation measures.
- Kampong Cham: The present warning flood stage of the Mekong
at Kampong Cham needs urgent review since in the recent
past, during 2000, 2001, 2002, parts of the city were flooded
despite the fact that the flood stage of 16.20 masl had
not been reached. Frequency analyses of long term annual
maximum water levels between 1930 and 2006 indicate that
the flood warning stage of 15.20 masl has a return period
of less than 4 years.
- Kratie: The western part of the town was flooded at a
Mekong River level of 22.05 masl, noting that the flood
level at the hydrometric gauge is 21.9 masl. (Appendix 2).
The 2006 maximum flood did not reach the warning level at
any of the villages equipped with flood referencing facilities.
It would be useful to establish the flood marks from the
most recent 2000–2002 floods at each village as reference
levels for issuing flood warning.
- Kratie: The province has identified a total of 97 safe
areas. Some provide emergency living accommodation during
floods while others provide refuge for farm stock, which
is generally the major family asset. Accessibility can be
difficult during the dry season since access roads can be
very poor. During the flood season, however, they are easily
accessible by boat. One pilot site with an area of 55 ha
has been identified and will be equipped with facilities
such as water supply, sanitation and proper access roads.
- Stung Treng: The town has no protection from flood inundation,
which is mainly caused by high water levels in the Mekong
mainstream and backwater in three major local tributaries.
- Stung Treng:The strategic location of the Stung Treng
hydrometric station at the head of the major part of the
Cambodian floodplain downstream is a key element within
the regional flood forecasting network. The reliability
of the station is not, however, what it should be under
these circumstances. Forecasting accuracy could be improved
in conjunction with data observed at Siem Pang and Chant
Ngoy on the Sekong, at Andaung Meas, Veun Sai and Ban Kamphun
on the Se San and at the Lumphat on the Sre Pok. Some of
these stations, however, have ceased to operate and transmit
data due to poor maintenance schedules and a lack of investment
- Stung Treng. The reference levels used by the Regional
Flood Management and Mitigation Centre at the Stung Treng
are 10.7 masl for the alarm stage and 12.0 masl for the
flood stage. These correspond to annual return periods of
two and slightly less than fifteen years, which appears
to be inconsistent and illogical.
- Stung Treng: Provincially, 116 flood refuges have been
identified, though only a few are equipped with even basic
facilities such as water supply and toilets. Effective evacuation
to them during a flood emergency is a village responsibility,
though the capacity to organise and coordinate the process
is not well developed. Nor are the means in place to transmit
prompt flood warnings to vulnerable villages.