The Alaknanda River runs through the foothills of the Himalaya Mountains and is currently a major water source for northern India. I 2005 GMR Energy started developing a 330 mW hydroelectric dam and power plant on the riverbanks to help meet the growing seasonal demand for power in northern India.
The project includes a 40 m high dam, a 3 km long headrace tunnel and an underground penstock leading to an underground power station with two 70 mW run of river turbines. The total head of water on the project is 480 m. The dam and power plant is located just outside the town of Srinagar in Uttarakhand (formerly Uttaranchal) State in northern India. This site was chosen due to its location on the river and proximity to mountain run off. It provided the best chance to develop hydroelectricity and manage the level of the river.
The site is nestled in a mountain valley. While the surrounding mountains are vast and breathtaking, it is a very remote region that presents challenges to travel and year-round work schedules. Getting to the site requires a 340 km drive from New Delhi on sometimes unreliable, winding mountain roads, which can take 12 to 14 hours in travel time. The location has snowfall for between four and six months a year, so construction cannot take place during the winter. As a result, it is anticipated that it will take about double the normal length of time to complete a project of this kind. The project is scheduled to achieve commercial operation in 2014. After which, most of the power generated by the dam and power plant will be channeled to serve the national capital territory of Delhi, the second largest metropolitan area in India with a population of nearly 14 million people.
In addition, it is an active seismic zone at risk of earthquakes. In September 1803, the area suffered a powerful earthquake that shook the whole region and devastated the town of Srinagar. As a result, the engineering and construction teams have taken noticeable steps to improve the soil stabilization on the slopes surrounding the project area. Concrete is bound to crack if it is not properly placed or cured. Therefore, waterproofing concrete with a straightforward, dependable and guaranteed system offers an indispensable level of protection, particularly for dam walls with steel reinforcement. If water enters cracks in the concrete, it can damage the reinforcing steel below the concrete surface. Steel expands when it corrodes, which leads to more cracks and water ingress. Over time, the concrete deteriorates and fails, which can result in devastating Hoods. The town of Srinagar is all too familiar with the devastation of floods.
In August 1894, over 10,000 mil cu ft. of water from the breached Gohna Lake completely swept away the original town of Srinagar. Modern day Srinagar was re-established by the British between 1897 and 1899. They used urban planning methodology to create a new grid-iron patterned town on the upper third terrace southeast of the previous city site. The town was granted urban status in 1931 and today is a major economic, cultural and, educational center in the region.
Building a strong structure due to the extreme risk potential in building or waterproofing a dam, governments and engineers are turning increasingly to integral crystalline waterproofing manufacturers for help. Integral systems can add decades to the life of a concrete structure. Unlike membrane systems that can deteriorate over time, integral systems become part of the concrete matrix, waterproofing from the inside out. This gives these systems added reliability over other waterproofing systems as they cannot be punctured or torn. In addition, integral systems will not be worn away by constant exposure to water, salts or other contaminants and are not affected by UV rays or concrete expansion and contraction. Finally, integral systems are a green solution. They can extend the serviceable life of structures by decades and also allow the concrete to be recycled after its useful life is over. For hydroelectric dams, which are a green form of energy, integral waterproofing systems make sense.
Kryton became involved in the project in 2010 after taking part in a site review meeting. The company is working with the on-site Ready Mix plant to optimize the mix design. Achieving the optimum mix is proving to be challenging due to the vast annual temperature fluctuation at the site. In addition, Kryton is helping the on-site construction team to test and apply its surface-applied waterproofing system, Krystol T1 and T2, and its internal system, Krystol lnternal Membrane (KIM), to the dam face, canal and two tunnels.
Going forward, the 1.8 km long canal leading to the pen stocks and two spillway tunnels that are each 1 km long will be waterproofed entirely using KTM. Krystol T1 and T2 will be applied to the upstream section of the dam face, which measures 128 m by 340 m. In all, approximately 1,000t of Kryton’s waterproofing systems will be used to treat tens of thousands of square meters of concrete.
Enquiry: jwork@kryton.com
