Abstract:
The present investigation is an effort to prioritize the subwatersheds of the Ret
watershed using morphometric parameter to identify the suitable sites for soil
and water conservation measures. The Ret watershed was delineated into 26
subwatershed and morphometric parameters namely bifurcation ratio, form
factor, circularity ratio, elongation ratio, drainage density, stream frequency,
drainage texture were derived independently for each of the subwatersheds.
Based on the Morphometric parameters watershed prioritization was carried
out and water resource management plan were derived by integrating land
use/cover, soil and slope information with morphological parameter. The
highest value of bifurcation ratio, drainage density, stream frequency, drainage
texture among 26 subwatersheds was assigned a rating of 1, the next highest
values was given rating of 2, and so on. For the shape parameters i.e. form
factor, circularity ratio, elongation ratio, the lowest value was given a rating of
1, the next lowest value was given a rating of 2, and so on. Integration of the
above seven parameters was done using simple summation of ratings. Based
on the average value of these parameters, the subwatershed having the least
rating value was assigned the highest priority number of 1, the next highest
value was assigned a priority number 2, and so on. Based on the average value
of these parameters, the subwatershed having the least rating value was
assigned the highest priority and vice versa. The subwatersheds were
classified into the five scales of priority, namely: very high, high, medium,
low and very low. Among the identified subwatersheds in the Ret watershed,
six subwatersheds covering an area of 66.5 km2 falls under very high category.
The count of subwatersheds which fall under high, medium, low and very low
priority class are five each and covering an area of 61.7, 58.27, 39.62 and
31.84 km2 respectively.
Based on the morphometric parameter, stream order, slope category, land
use/land cover, soil type of the subwatersheds, suitable sites for check dams
were identified and marked in the map for very high, high, medium, low and
very low priority areas of the Ret watershed. In view of the requirement of soil
and water conservation measures, it has been proposed to construct 11
numbers of check dams in subwatershed numbers 1, 4, 5, 6, 7, 8, 9, 10, 12, 22,
and 24.
