Abstract:
Waterlogging has significantly affected the cane agriculture at WSSE, which is the oldest
sugarcane plantation in the country established for commercial sugar production. A study was
undertaken to assess the temporal pattern and spatial distribution of GWT in the estate, to evaluate
the effect of rehabilitation works on the level and distribution of GWT and to map the GW
distribution in the cane plantation. GWT data was collected in representative sites throughout the
cane plantation. ArcGIS (ver. 9.2) of ESRI was used for mapping the spatial distribution of GW in
the cane plantation of the estate. The study indicated that 14% and 60% of the cane area were in
most severely waterlogged and critically waterlogged condition, respectively. The study also
revealed that deep percolation from reservoirs and seepage from big unlined supply canals had
been the most contributing factors for the development of shallow GWT in the cane plantation.
Cane fields near deep drainage channels had showed consistently lower GW levels indicating that
improved drainage helps to lower the level of GW in the cane plantation. On the other hand, lack of
proper maintenance of the field drainage system and lack of proper infield irrigation water
management are identified to be the causes for the increase in GW level in the area affected by
severe waterlogging. Hence, it is recommended to practice improved irrigation management in the
cane plantation by taking into account the contribution of GW to crop water requirement and to
undertake regular and proper maintenance of the infield and main drainage channels. It is also
recommended to undertake regular monitoring of the GW level in the cane plantation to establish
the temporal trend in GW level taking into consideration of all contributing factors for the rise in
GW level in the cane plantation and establish a critical GW level for sustainable sugarcane
production in the estate.
