Hirakud Dam Project is built across river Mahanadi at about 15 Kms. upstream of Sambalpur town in State of Odisha. This happens to be the first post independence major multipurpose river valley project in India. The dam is 6 Kms from NH 6 . The nearest rail head is Hirakud railway station (S.E.R) which is 8 Kms from the dam site.
The project provides 1,55,635 Hects of Kharif and 1,08,385 Hects of Rabi
irrigation of Sambalpur, Bargarh, Bolangir, and Subarnpur. The
water released through power house irrigates further 436000 Hects of CCA in
Mahanadi delta. Installed capacity for power generation in 307.5 MW through its
two power houses at Burla , at the right bank to and Chiplima , at 22 Kms down
stream of dam . Besides the project provides flood protection to 9500 sq Kms of
delta area in district of Cuttack and Puri.
Brief history of the Project:
After high floods of 1937, Sir M. Visveswararya gave proposal for
detailed investigation for storage reservoirs in Mahanadi basin to tackle
problem of floods in Mahanadi delta,
In 1945, it was decided under the chairmanship of Dr. B.R.Ambedkar, the then
Member of Labour in Govt. of India that the potentialities of river Mahanadi
should be fruitfully and expenditiously investigated for multipurpose use.
Central Water- ways Irrigation and Navigation Commission took up the work. The
foundation stone of Hirakud Dam was laid by Sir Howthrone Lewis, the then
Governor of Odisha on 15th March 1946. The project report was
submitted to Government in June 1947. The first batch of concrete was laid by
Pandit Jawaharalal Neheru on 12th April 1948. The project was
formally inaugurated by Prime Minister Pt. Jawaharlal Nehru on 13th,
January 1957. Power generation along with supply for irrigation started
progressively from 1956 and full potential was achieved by 1966.
dam is a composite structure of Earth,
Concrete and Masonry. The main dam
having an overall length of 4.8 K.m. spans between hills Lamdungri on left hand
Chandili Dunguri on the right. The Dam is flanked by 21 K.Ms. long earthen dykes
both on left and right sites to close the low suddles beyond the abutment hills.
It has the distinction of being the longest dam in the world, being 25.8
K.Ms. long with dam and dykes taken together.
It has also the rare distinct of forming the biggest artificial lake in
Asia with reservoir spread of 743 sq Kms at full reservoir level.
dam intercepts 83400 sq. km (32200 sq miles) of Mahanadi catchments. The
reservoir has a storage of 5818 M. Cum with gross of 8136 M Cum.
Cost: The Completed Cost of the Project was Rs.100.02 crores (in 1957)
(a) Catchment - 83400 Sq. Kms (32200 sq miles)
(b) Rain fall(mm) - Original Revised
Mean annual - 1381(1900 – 45) 1088
Maximum annual - 1809 (in 1919) 2518
Minimum annual - 940 (in 1902) 607
Run Off (M Hect. M)
Average annual 6.17 3.36
Maximum annual 8.62 9.09
Minimum annual 2.54 1.14
(B) DAM AND RESERVOIR
Top dam level R.L 195.680M. (R.L.642 ft.)
F.R.L/ M. W. L R.L 192.024M (R.L 630 ft.)
Dead storage level R.L 197.830 M (R.L 590 Ft)
Storage capacity Original Revised
In M Cum (M. Ac. Ft.) (1988)
Gross 8136 (6.60) 7189 (5.83)
Live 5818 (4.72) 5375 (4.36)
Dead 2318 (1.88) 1814 (1.47)
Water spread area at F.R.L 743 Sq. Km.
At D.S.L 274 Sq. Km.
Maximum fetch At F.R.L 83.2 Km.
Total length of Dam 4800 M.
Length of dyke, Left Dyke 9337 M in five gaps.
Right Dyke 10759 M in one stretch.
Total quantity of earth work in Dam 18.1 M Cum.
Total quantity of concrete and
1.07 M. Cum
Spillway capacity 42450 cumecs (15 lakhs cusecs)
Crest level - R.L. 185.928 M ( R.L. 610 ft.)
Size of sluices - 3.658 x 6.20 M (12x 2034 ft)
No. of sluices - 64 (40 on left and 24 on right)
Sill of sluices - R.L. 155.448 M (R.L. 510 ft)
No. of crest gates - 34 ( 21 on left and 13 on right)
Size of crest gates - 15.54 M x 6.10 M. (51x 20 ft.)
Types – Solid gravity with ogee
profile and skijump bucket.
(D) POWER GENERATION:
At Burla - 5 x 37.5
2x24.0 = 235.50 MW
At Chiplima - 3x24 = 72.00 MW
= 307.50 MW
Length of the power channel - 22.40 Km.
Full supply discharge of power - 22.40 Km
channel (beyond escape)
Full supply discharge of chiplima P.H. – 333.4 cumecs.
Bed width of power channel ;
Upto escape -75.5 M
Beyond escape - 52.5 M