By means of an outlet, water from the reservoir is discharged into a main
concrete channel (Fig. 3.9). A common irrigation system then distributes the
water, via this concrete channel and through the rice paddy cascades and fish
ponds, into the natural stream. An overspill limits the maximum water level of
the reservoir to 11.9 m. Typical water level patterns in the reservoir and monthly
precipitation for the years 2006–2008 are depicted in Fig. 3.6.
The seasonal fluctuation of the water level in the reservoir is mainly governed by
the annual precipitation pattern. During the dry season, the water level continuously
declines, typically reaching a minimum in May/June. With the onset of the wet
season, intensive precipitation events provoke a rapid refilling of the reservoir
within a few weeks. From the middle of the wet season onwards; however, when
the water level of the reservoir commonly exceeds the critical height of the
overspill, unregulated run-off is triggered from the reservoir directly into the natural
stream (Schad et al. 2012). The year to year differences in water level fluctuations,
as depicted in Fig. 3.6, illustrate the uncertainties that water resource managers
have to deal with in order to meet annual irrigation demands.
As a consequence of the public agricultural collectivization programs accomplished in the 1970s, the traditional communal water governance system underwent
major changes, resulting in more pluralistic structures being developed (Neef et al.
2006). After the completion of the dam; for example, the position of Lake Manager
was established in Chieng Khoi by the Provincial Department for Irrigation.
Together with his co-workers, the Lake Manager has to report directly to the
Provincial Department. It is worth mentioning that the lake management team;
however, typically consists of the residents of places other than Chieng Khoi, and as
a consequence, contact with local residents is minimal, alienating the locals from
Fig. 3.6 Water levels in the Chieng Khoi reservoir plus cumulative monthly precipitation for the
years 2006, 2007 and 2008 (Modified from Schad et al. 2012)
122
H.L. Fro ¨hlich et al.
concrete channel (Fig. 3.9). A common irrigation system then distributes the
water, via this concrete channel and through the rice paddy cascades and fish
ponds, into the natural stream. An overspill limits the maximum water level of
the reservoir to 11.9 m. Typical water level patterns in the reservoir and monthly
precipitation for the years 2006–2008 are depicted in Fig. 3.6.
The seasonal fluctuation of the water level in the reservoir is mainly governed by
the annual precipitation pattern. During the dry season, the water level continuously
declines, typically reaching a minimum in May/June. With the onset of the wet
season, intensive precipitation events provoke a rapid refilling of the reservoir
within a few weeks. From the middle of the wet season onwards; however, when
the water level of the reservoir commonly exceeds the critical height of the
overspill, unregulated run-off is triggered from the reservoir directly into the natural
stream (Schad et al. 2012). The year to year differences in water level fluctuations,
as depicted in Fig. 3.6, illustrate the uncertainties that water resource managers
have to deal with in order to meet annual irrigation demands.
As a consequence of the public agricultural collectivization programs accomplished in the 1970s, the traditional communal water governance system underwent
major changes, resulting in more pluralistic structures being developed (Neef et al.
2006). After the completion of the dam; for example, the position of Lake Manager
was established in Chieng Khoi by the Provincial Department for Irrigation.
Together with his co-workers, the Lake Manager has to report directly to the
Provincial Department. It is worth mentioning that the lake management team;
however, typically consists of the residents of places other than Chieng Khoi, and as
a consequence, contact with local residents is minimal, alienating the locals from
Fig. 3.6 Water levels in the Chieng Khoi reservoir plus cumulative monthly precipitation for the
years 2006, 2007 and 2008 (Modified from Schad et al. 2012)
122
H.L. Fro ¨hlich et al.