Perunchani Dam, Kalkulam, Kanyakumari
Perunchani
Dam is an irrigation dam located at Perunchani in Kalkulam Taluk in Kanyakumari District of Tamilnadu. It
is one of the dams of the Kodayar Irrigation System. As there was water
deficiency in the Kodayar Irrigation System, Perunchani Dam was constructed in
December 1952 to store flood water of the Paralayar River as an extension. It
was built about 1 km (0.62 mi) upstream of the Puthen dam on the Paralayar
River. The irrigation system became operational on 2 September 1953. It feeds
the left bank irrigation canal system of the Puthen dam, which is the terminal
structure of the system. The dam is set amidst the hills of the Western
Ghats and commands a picturesque view of the hills and lush greenery around.
Topography
The dam
is built between two hillocks (part of the Western
Ghats) across the Paralayar River, a
tributary of the Tamiraparani River, also known locally as the Kuzhithuraiar, and is part
of the basin that constitutes the west-flowing rivers from Tadri to Kanyakumari. Tamiraparani River rises in the Western
Ghats and flows through a distance
of 56 km (35 mi) before debouching into the Arabian
Sea. The catchment
area at the Perunchani Dam site is
158.4 km2 (61.2 sq. mi). The reservoir is thickly forested
and inhabited by wild animals such as tiger, elephants, and deer. The tribal
community of Kanikars resides around the periphery of the reservoir. The
average annual rainfall in the catchment is 2,240 mm (88 in), and the
average annual yield at the dam site is
218,000,000 m3 (7.7×109 cu ft).
The Dam
The dam
is built across the River Paralayar. It is a straight gravity masonry dam of
373.10 meters long consisting of 275.28 meters of bulk head section. A drainage
gallery of 1.52 x 2.29 M has been provided in the middle river section for a
length of 45.70 M which serves a longitudinal inspection chamber as well as
out-let for the seepages from the foundation. The dam was constructed between
1948–1953 by the then State of Travancore-Cochin.
The
height of the straight gravity masonry dam above the deepest foundation is
36.27 m (119.0 ft), with Full Reservoir Level (FRL) at 93.3 m
(306 ft), which is also the Maximum Water Level (MWL). The dam is
308 m (1,010 ft) long. The gross storage capacity of the reservoir is
818,400,000 m3 (2.890×1010 cu ft) at the FRL, which is also
the effective storage capacity. The reservoir area is 9,620 ha (23,800
acres).
The
spillway, with its crest at 88.7 m (291 ft), is designed to pass a
discharge of 894.91 m3 (31,603 cu ft) per second. There are
four spillway gate openings, each 12.19 m × 4.57 m (40.0 ft
× 15.0 ft) in size. The total volume of material content in the dam
is 51,000 m3 (1,800,000 cu ft). The project lies in Seismic Zone-III. The dam is provided with drainage gallery of
45.7 m (150 ft) length in the central section of the river.
It
serves the purpose of collecting seepage water from the foundation of the dam
and also as an inspection gallery, and measures 1.52 m × 2.29 m
(5 ft 0 in × 7 ft 6 in). The fishing operation in the
reservoir is limited to the indigenous Puntus spp. This dam is situated
amidst the lush green scenic hills of Western Ghats and command panoramic views
of lush greenery and stunning hills around.
Irrigation
System
The dam
is part of the Kodayar Irrigation System, as its stored waters are utilized
only through a combined canal system which provides irrigation to a total
command area of 36,836 ha (91,020 acres). The irrigation system consists
of four dams and associated storage reservoirs, anicuts, and canal system. The first project to be
implemented under this system was the Pechiparai dam, built during 1948-53; the Kodayar Left Bank Canal
(KLBC) taking off from this dam feeds the Puthen dam, which is a weir that was remodeled under World
Bank assistance during the 2000s. The next two dams to
be built were the Chittar dam I and Chittar dam II in the period from
1964-1970; the storage waters of these two reservoirs were also fed into the
KLBC. The storage from the Perunchani reservoir is also fed into the Puthen
weir.
During
the period 1964-70 the storage capacity of the Pechiparai and Perunchani dams
was increased by raising the full reservoir level by 1.83 m (6 ft
0 in); this involved rising, strengthening, and improvement measures. The
KLBC, which was originally designed to carry a discharge of 24.07 m3 (850 cu ft)
per second, was remodeled in 1965 to carry a discharge of
32.99 m3 (1,165 cu ft) per second. There is a small branch
canal taking off from the KLBC, before it joins the Puthen weir, which has an
irrigation command of 6,073 ha (15,010 acres). The interlinking of
the Perunchani and Chittar dams provides an additional irrigation potential of
15,000 acres (6,100 ha) in the system.
Connectivity
The Dam
is located at about 4 Kms from Ponmanai, 11 Kms from Kulasekharam, 16 Kms from Thiruvattaru,
14 Kms from Thirparappu, 23 Kms from Marthandam, 25 Kms from Kuzhithurai, 20
Kms from Thuckalay, 21 Kms from Padmanabhapuram, 30 Kms from Colachel, 33 Kms
from Nagercoil, 24 Kms from Boothapandi, 60 Kms from Kanyakumari and 66 Kms
from Thiruvananthapuram. Nearest Railway Station is located at Kuzhithurai and
Nearest Airport is located at Thiruvananthapuram.
