Mullaperiyar- A Water Bomb

Dam Accidents Analysis & Mullaperiyar factsheet : 

Dam Accidents Analysis & Mullaperiyar factsheet

Hydroelectric dam accidents : 

Hydroelectric dam accidents Hydroelectric dams can supply relatively clean electricity as well as flood control and recreation benefits. While very rare, dam failures release massive amounts of water that cause severe floods, landslides, structural damage, and in some cases, great loss of human life.

Dam safety depends on five factors:: 

Dam safety depends on five factors: Complete investigations; Adequate design; Quality construction; Appropriate operation, maintenance and supervision; Adequate alarm mechanism and well-adapted emergency action plans.

The probability of failure of a dam depends on many factors:: 

The probability of failure of a dam depends on many factors: Spillway capacity; Seismic resistance; Nature of the foundations (a dam founded on bed rock is less vulnerable); Quality of design (Competence of the design engineers, verification methods); Quality of Construction (Competence of the contractor and the supervision); Monitoring; Maintenance; Human factors (Social conflict, terrorism, war etc.)

The Catastrophic Dam Failures: 

The Catastrophic Dam Failures Banqiao Reservoir Dam China- infamously failed in 1975, causing more casualties than any other dam failure in history, and was subsequently rebuilt.

Banqiao Reservoir Dam China: 

Banqiao Reservoir Dam China Begun in April 1951 with the help of Soviet consultants as part of a project to control flooding and to generate electricity, The dam was completed on June 1952 Dam failure killed an estimated 171,000 people; 11 million people lost their homes

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loss of 18 GW of power, the equivalent of roughly 9 very large modern coal fired power stations or about 20 nuclear reactors. The dam crest level was 116.34 meters above sea level and the crest level of the wave protection wall was 117.64 meter above sea level. The total capacity of reservoir was 492 million m³ (398,000 acre feet), with 375 million m³ (304,000 acre feet) reserved for flood storage. The dam was 24.5 meters high. The maximum discharge of the reservoir was 1742 m³/s. The Dam was designed to survive a once-in-1000-years flood (300 mm of rainfall per day). In August 1975, however, a once-in-2000-years flood occurred, produced by the collision of Super Typhoon Nina and a cold front. This precipitated the failure of 62 dams in total.

PowerPoint Presentation: 

The resulting flood waters caused a large wave, 10 kilometers (6.2 mi) wide and 3–7 meters (9.8–23 ft) high in Suiping to rush onto the plains below at nearly 50 kilometers per hour (31 mph), almost wiping out an area 55 kilometers long and 15 kilometers wide, and creating temporary lakes as large as 12,000 square kilometers (4,600 sq mi). To protect other dams from failure, several flood diversion areas were evacuated and inundated, and several dams deliberately destroyed by air strikes to release water in desired directions. Casualties According to the Hydrology Department of Henan Province[citation needed], in the province, approximately 26,000 people died[11] from flooding and another 145,000 died during subsequent epidemics and famine. In addition, about 5,960,000 buildings collapsed, and 11 million residents were affected. Unofficial estimates of the number of people killed by the disaster have run as high as 230,000 people. The death toll of this disaster was declassified in 2005 After the disaster of the Banqiao dam failure, the Chinese government became very focused on surveillance, repair, and consolidation of reservoir dams.

Vajont Dam - Italy: 

Vajont Dam - Italy Before After

PowerPoint Presentation: 

Vajont Dam is a hydroelectric dam completed in 1960 under Monte Toc, 100 km north of Venice, Italy. During the filling of the reservoir on October 9, 1963, a block of approximately 270 million m3 detached from one wall and slid into the lake at velocities of up to 30 m sec-1 (approx. 110 km h-1). This generated a wave that topped the dam by 245 m and swept onto the Longarone Valley below, with the loss of about 2500 lives. Remarkably, the event did not destroy the entire dam. It was built as a part of the post-war development of Italy in order to provide energy for the rapidly-expanding northern cities of Milan, Turin and Modena. Excavation of the site began in 1956 and the dam was completed in 1960. The completed doubly curved arch dam was, at 265.5 meters above the valley floor, the worlds highest thin arch dam. The chord of the dam was 160 m, and the volume of impounded water was 115 million m3.

PowerPoint Presentation: 

Events during the filling of the reservoir indicated that landslides posed a serious risk. Filling was initiated in February 1960, but on three separate occasions the reservoir level had to be drawn down due to the induced movements or "creeps" of material down the left bank above the reservoir. Engineers believed they could prevent a landslide by controlling the rate and timing of the reservoir filling. The third filling brought the level of the reservoir to a depth of 235 meters by late September 1963. At 22:38 GMT on October 9 1963 catastrophic failure of the landslide occurred. The entire mass slid approximately 500 m northwards at up to 30 m sec-1. The mass completely blocked the gorge to a depth of up to 400 m , and it traveled up to 140 m up the opposite bank. At the time the reservoir contained 115 million m3 of water. A wave of water was pushed up the opposite bank and destroyed the village of Casso , 260 m above lake level before over-topping the dam by up to 245 m. The water, estimated to have had a volume of about 30 million m3, then fell more than 500 m onto the villages of Longarone, Pirago , Villanova, Rivalta and Fae , totally decimating them. A total of about 2500 lives were lost. The dam was not destroyed and is still standing today. The by-pass tunnel is used for the generation of electricity.

Dam Accidents In India: 

Dam Accidents In India

Data Sheet - Mullaperiyar: 

Data Sheet - Mullaperiyar

PowerPoint Presentation: 

Mullaperiyar is derived from a portmanteau of Mullayar and Periyar, at the confluence of the dam is located. Mullaperiyar Dam is a masonry gravity dam over Periyar River and its tributary Mullayar, hence Mullaperiyar. Entirely inside Kerala, but operated by Tamilnadu as per 125 year old British agreement.

PowerPoint Presentation: 

At 176 ft (54 m) in height and 1,200 ft (366 m) long, it is located 2,889 ft (881 m) above mean sea level on the Cardamom Hills of Western Ghats in Thekkadi, Idukki District of Kerala, India. It was constructed in 1895 by the British Government From Periyar Thekkady reservoir, water is diverted eastwards to Tamil Nadu via a tunnel enabling the water to join the Vaigai River.

PowerPoint Presentation: 

While constructing they predicted the age of 50 years with 999 years agreement, but it completed 125 years by now. It is used for irrigation and power generation. The Periyar Power Station in Lower Periyar, Tamil Nadu generates hydro-electricity from the diverted waters. was 173 feet high and 1241 feet in length along the top and enclosed more than 15 thousand million cubic feet of water

Lease: 

Lease On 29 October 1886, a lease indenture for 999 years was made between Maharaja of Travancore, Vishakham Thirunal and Secretary of State for India for Periyar irrigation works. The lease agreement was signed by Dewan of Travancore V Ram Iyengar and State Secretary of Madras State (under British rule) J C Hannington . This lease was made after constant pressure on Travancore King by the British for 24 years. in 1970 when C Achutha Menon was Kerala Chief Minister. According to the renewed agreement, the tax per acre was 30 RS, and for the electricity generated in Lower Camp using Mullaperiyar water, the charge was 12 RS per kiloWatt per hour. Tamil Nadu uses the water and the land, and the Tamil Nadu government has been paying to the Kerala government for the past 50 years 2.5 lakhs Rs as tax per year for the whole land and 7.5 lakhs RS per year as surcharge for the total amount of electricity generated

Current status: 

Current status Tamil Nadu is the custodian of the dam and its surrounding areas. In 2006, the Supreme Court of India by its decision by a single bench, allowed for the storage level to be raised to 142 feet (43 m). By considering the weak structure the water level is brought to 132 feet. Kerala's Stance: Kerala did not object giving water to Tamil Nadu. Their main cause of objection is the dams safety as it is as old as 110 years. Increasing the level would add more pressure to be handled by already leaking dam. No masonry dam may survive for 999 years so a new dam may replace the existing one in near future.

If some thing goes wrong?: 

If some thing goes wrong? If an earthquake of magnitude 6 happens? Kerala will be split into two 30 Lakh people will flow to sea Many major Kerala cities goes into water. Water will reach Cochin in 3 hours Huge water flow to Idukki Dam(Another biggest- 30 km away from mullaperiyar ) and if it breaks it leads to breakage of 11 small dams.

What we can do?: 

What we can do? Kerala’s slogan is ‘Water For Tamil Nadu, Safety For Kerala’ Let us hope brothers of Tamilnadu will realise the fact and co-operate for a new dam, with ‘they getting same amount of water as now’, even though the dam is inside Kerala.