The largest Earth Dam in India is Banasura Sagar Dam which impounds ‘Karamanathodu’ a tributary of Kabini River and is part of major project taken up by the Government Of India in 1979 to support irrigation and domestic needs for water of a region facing scarcity of water during the dry seasons and also to support Kakkayam Dam by supplying water. The Banasura Sagar Dam was commissioned in 2005 and supports Kakkayam Hydroelectric Power Project.
The dam is the largest earth dam in India and the second largest in Asia and is named after ‘Banasura’ – a Hindu mythological figure and son of Bali.
The dam is the most sought after tourist destination of North Kerala and offers nature in its pristine forms surrounded by lush green landscapes.
Location of Banasura Sagar Dam
The dam lies in the Western Ghats region of the southern state of Kerala. It is located at a distance of 22 km from the municipal town of Kalpetta which is the headquarter of Wayanad District as well as Vythiri Taluka. Kalpetta is at a distance of 72 km from Kozhikode and about 140 km from Mysore.
The drive from Kalpetta to Banasura Sagar Dam on SH 54 is around 20 km and takes around 50 minutes; through lush green hills, tea estates and sugarcane fields. Even the dam offers a greener view that is otherwise absent in conventional masonry dams.
The dam lies at the foot of Banasura Hill, which is also the highest hill of Western Ghat in Wayanad District.
Technical Details of the Dam
The Banasura Sagar Dam is an earthen dam made from huge piles of stones and boulders. The spillway of the dam consists of four Tainter Gates. Tainter Gates has a cross-section looking like a triangle with a curved base. The total spillway discharge capacity of the dam is 208.25 cumecs (cubic meters per second).
The Full Reservoir Level (FRL) of the Banasura Sagar Reservoir is 775.6 mtr (Above MSL i.e. Mean Sea Level) and the minimum drawdown level of 754.86 mtr (Above MSL). The reservoir has a water spread area of 12.77 sq km (1277 hectares) and a catchment area of 61.44 sq km (6144 hectares). The maximum storage of the reservoir at full water level is 209 MCM (million cubic meters).
The Banasura Sagar Dam, along with Kakkayam Dam across the Kuttiady River; supports the Kuttiady Hydroelectric Project with a total installed capacity of 220 MW. The two reservoirs are inter-connected to each other by a tunnel of length 4.678 meters. The project has four different functional entities and one under construction.
The following power stations are supported by the waters from the Banasura Sagar Dam and Kakkayam Dam-
1) Kuttiady Old Power House
The Kuttiadi Old Power station has a total installed capacity of 75 MW. It was commissioned on 30th September 1972 and has three M/S Fuji Electric made Vertical Pelton Turbines of individual capacity 25 MW. The annual generation potential of the station is 268 Million Units.
2) Kuttiady Extension Scheme (KES)
Under this scheme, an additional unit of 50 MW was installed nearby the old powerhouse. It consists of a Single Pelton Turbine of 50 MW capacity made by the General Electricals, Canada. The unit was commissioned on 27th January 2001 and has an annual generation capacity of 75 Million Units.
3) Kuttiady Additional Extension Scheme (KAES)
The Kuttiady Additional Extension Scheme (KAES) was executed by constructing a powerhouse adjacent to the Kuttiady Extension Scheme (KES). It was mainly constructed to counter the spillover during monsoons. A tunnel of 686 meters long and a penstock of length 2 km were also made under the scheme. The powerhouse has a total capacity of 100 MW with two Vertical Pelton Turbines of the individual capacity of 50 MW. The first and second units were commissioned on 11th Oct. 2010 and 30th Oct. 2010 respectively and the plant has an annual generation capacity of 223 Million Units.
4) Kuttiady Tail Race Small Hydro Project
This scheme uses the water discharged from the Kuttiady Old Power House and Kuttiady Extension Scheme (KES). It houses three Horizontal Kaplan Turbines of 1.25 MW individual capacity and Boving Fouress make. The first, second and third units were commissioned on 19th June 2008, 22nd June 2008 and 23rd Oct. 2008 respectively. This unit has a total installed capacity of 3.75 MW and an annual generation capacity of 15 Million Units.
5) Kuttiady Small Hydroelectric Project
This is an under-construction project aimed at utilizing the tailwater of the Kuttiady Additional Extension Scheme (KAES) to power two turbines of the individual capacity of 1.5 MW.
India’s First Solar Atop Dam
A solar project is installed on the top of the Banasura Sagar Dam by the Kerala State Electricity Board (KSEB); which is the fifth such project in Kerala and the second in Wayanad. The project incurring a cost of around INR 4 crores to KSEB and generating five lakh units annually was commissioned in 2016 by Kerala’s State Power Minister, Kadakampally Surendran.
The project has 1760 panels with an individual capacity of 50 KW installed over a 285 meters stretch of the dam’s top road.
The location of the dam at the foot of a hill in the Western Ghats, surrounded by greenery makes it Kerala’s one of the most popular tourist destinations. Trekking on the Banasura Hills and high-speed boating in the Banasura reservoir are some of the major attractions of the dam. The reservoir also has many tiny islands covered with greenery which offer a rejuvenating experience away from hectic city life.
FAQs about Banasura Sagar Dam
Q1) Which is the largest Earth Dam in India?
Ans- The Banasura Sagar Dam is the largest earth dam in India and the second largest in Asia.
Q2) Where is the dam located?
Ans- The dam is located in the Western Ghats in Wayanad District in the state of Kerala.
Q3) Across which river is the dam located?
Ans- The Banasura Sagar Dam is located across the Karamanathodu River, a tributary of the Kabini River.
Q4) When was the Banasura Sagar Dam commissioned?
Ans- The dam was commissioned in 2005.
Q5) Which other dam was the Banasura Dam built to supply water to?
Ans- The Banasura Sagar Dam was built to supply water to Kakkayam Dam.
Q6) After which mythological figure is the dam named?
Ans- The dam was named after the Hindu mythological figure of Banasura; son of Bali.
Q7) How far is the dam from Kozhikode?
Ans- The dam is around 72 km from Kozhikode.
Q8) Which hill is located in the background of the dam?
Ans- The dam lies at the foot of Banasura Hill.
Q9) What kind of dam is it?
Ans- It is an earthen dam made from stacks of stones and bricks.
Q10) How many spill gates does the dam has?
Ans- The dam has four Tainter Gates.
Q11) What is the total spillway capacity of the dam?
Ans- Total spillway discharge capacity of the dam is 208.25 cumecs.
Q12) What is the Full Reservoir Level (FRL) of the Banasura Sagar reservoir?
Ans- Full Reservoir Level is 775.6 meters above MSL.
Q13) What is the Minimum Drawdown Level of the reservoir?
Ans- Minimum Drawdown level is 754.86 meters above MSL.
Q14) What is the water spread area of the reservoir?
Ans- Water spread area of the reservoir is 12.77 sq km.
Q15) How much is the total catchment area of the reservoir?
Ans- The total catchment area of the reservoir is 61.44 sq km.
Q16) What is the total capacity of the reservoir?
Ans- The reservoir has a total capacity of 209 MCM.
Q17) What is the total installed capacity of the Kuttiady Hydroelectric Project?
Ans- The total installed capacity of the Kuttiady Hydroelectric Project is 220 MW.
Q18) How are the Banasura Sagar and Kakkayam reservoirs inter-connected?
Ans- By a 4.678-meter long tunnel.
Q19) What are the Power Stations under the Kuttiadi Hydroelectric Project?
Ans- Following are the Power Stations under the Kuttiadi Hydroelectric Project:
- Kuttiady Old Power House
- Kuttiady Extension Scheme (KES)
- Kuttiady Additional Extension Scheme (KAES)
- Kuttiady Tail Race Small Hydro Project
- Kuttiady Small Hydroelectric Project
Q20) How much is the installed capacity and annual generation of Kuttiady Old Power House?
Ans- 25 MW and 286 MU respectively.
Q21) How much is the installed capacity and annual generation of the Kuttiady Extension Scheme?
Ans- 50 MW and 75 MU respectively.
Q22) How much is the installed capacity and annual generation of Kuttiady Additional Extension Scheme?
Ans- 50 MW and 223 MU respectively.
Q23) How much is the installed capacity and annual generation of the Kuttiady Tail Race Small Hydro project?
Ans- 3.75 MW and 15 MU respectively.
Q24) What is the planned installed capacity of the Kuttiady Small Hydroelectric Project?
Ans- Planned capacity is 1.5 MW.
Q25) How much is the total capacity of Solar Project installed on top of the dam?
Ans- The solar project has a generation potential of 5 lakh units annually.
Q26) When was the Solar Project on Banasura Sagar Dam commissioned?
Ans- The project was commissioned in 2016.
Q27) What are the activities popular among tourists visiting the dam?
Ans- Following are the activities popular among tourists visiting the dam:
- Hiking on the Banasura Hill
- High-speed boat ride in the reservoir