Further, an increase in rainfall has contributed to the increase in water levels in
both canals. However, surface water level increased faster in Jajangkit compared to
Ulin (Fig. 20.14). The ranges of surface water level at Jajangkit during the dry
season, transitional, and rainy season were 59–112 cm, 50–91 cm, and 39–75 cm,
respectively, whereas at Ulin, they were 102–120 cm, 75–110 cm, and 54–100 cm.
Thus, the discrepancies of the canal surface water at Jajangkit and Ulin during the
rainy and dry season were around 9 cm and 22 cm, respectively.
20.4.3.4 Coefficient Correlation Dynamics between Ground and Surface
Water Level
The correlation between groundwater table and surface water level showed that
Jajangkit canal could raise both groundwater and surface water levels faster than
Ulin canal (Fig. 20.15). However, during the dry season the depth of GWL in both
locations reached more than 80 cm below the peat surface, but when entering the
transition time from dry to rainy season, GWL in Jajangkit area was around 20 cm
higher than that at Ulin area.
Fig. 20.9 Microtopography of Jajangkit canal area
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A. Dohong and L. Tanika