Abstract:
Iranamadu reservoir is the largest reservoir
in Northern Province of Sri Lanka, which is located in
Kilinochchi. Iranamadu tank is one of the ancient reservoir
in Sri Lanka, which was built in 5th century. Capacity
of the reservoir is 132 MCM and the catchment area of
the reservoir is 588 km2. The reservoir was enlarged
during the British era, and bund was raised up three
times. Objective of the study was to analyze rainfall data
and check whether data is statically suitable for further
hydrological modeling. Numbers of rain gauge stations,
which are available at Kanagarayan Aru river basin, were
selected for the study including Iranamadu, Vavuniya,
Vavunikulam, Mankulam, and Muthiyankaddu. Missing
rainfall data is estimated using simple arithmetic mean
and normal ratio method. Daily rainfall data from 2010
– 2016 was statically check for screening and consistency.
Outlier test and Spearman’s rank correlation test also
carried out for the data set. Results of the study are
revealed that rainfall data are statistically distributed
and suitable for further hydrological analysis.
