Carpi's Geosynthetics Usage in Hydraulic Structures
CARPI, established in 1963, has gained a worldwide experience and reputation in the field of waterproofing of all types of hydraulic structures by using synthetic geomembranes.
CARPI has installed PVC Geomembrane waterproofing systems on more than 260 hydraulic structures, (>4,500,000 sq. meters) including 160+ dams (> 1,200,000 sq. meters), and 50 canals and other hydraulic tunnels (>1,000,000 sq. meters) around the world.
Carpi headquartered in Switzerland has offices in 19 countries to cater to the waterproofing needs across all corners of the globe. CARPI provides owners and consulting engineers with investigations and recommendations to correct leakage or infiltration problems for almost any type of hydraulic structure. CARPI provides reliable and cost effective solutions, including final design and installation on any project worldwide.
CARPI's range of applications includes:
• Dams, all types (gravity, buttress, arch, multiple arches, roller compacted concrete (RCC), embankment, cofferdams)
• Pumped storage, reservoirs, water storage basins, floating covers
• Free flow canal and hydraulic tunnels
• Pressure tunnels and shafts
• Water supply and sewage systems
• Civil works (Foundation and roofing)
• Highway, railway and metro tunnels
• Underground structures (Surge chambers, access shafts to power plants, potable water storage structures)
• Floating covers to avoid air pollutant or liquid evaporation
• Synthetic diaphragms against pollutants.
THE USE OF WATERPROOFING geomembranes has been a milestone in the planning, design and construction of new embankment dams since 1959. In the first applications the geomembranes were covered. When more performing geomembranes came to the market in the 1970s, and innovative anchorage systems were developed, the use of geomembranes became possible in exposed positions. Exposed geomembranes allow further reducing time and costs as compared to traditional waterproofing facings. Geomembranes made feasible and profitable projects compared to the traditional waterproofing methods thereby reducing time and costs.
Geomembrane systems provide
• Water tightness
• Environmental sustainability
• Longevity of hydraulic structures
• Safety
Exposed geomembrane systems were first used in the rehabilitation of concrete, masonry and embankment dams to restore their watertightness over the whole upstream face or locally at joints/cracks . When new concept dams such as RCCs and hardfill appeared, the engineering of new geomembrane systems suitable for such dams followed closely. A few years after the first RCC dam was built, geomembrane systems started being adopted in the new construction of RCC dams or to restore their watertightness, over the whole upstream face or locally at joints/cracks, with systems similar to those used in rehabilitation of concrete and embankment dams. More recently, innovative geomembrane systems have been used in hardfill dams (Nam OU Dam, Refer Fig.1 and Concepcion, Refer Fig 2.), to provide a watertight facing as an alternative to the traditional reinforced concrete facings.
Geomembrane systems have a low impact on the environment because they do not require heavy site organization and equipment, they do not involve heavy traffic and pollution, and they can be installed in short times. In recent years, zero environmental impact was achieved by Carpi through the innovation brought forward by underwater rehabilitation techniques. (Studena Dam Ref Fig.3) This technique helped in the rehabilitation of dams, canals and other hydraulic structures, with a system that allows by restoring watertightness without stopping the water flow.
After the first full- face rehabilitation made on a dam in 1997 (Lost Creek dam, US), underwater systems have been developed and adopted on all types of structures, either for total or partial repair. In recent years, zero environmental impact has also been reached in the rehabilitation of canals, with a system that allows restoring watertightness without stopping the water flow.
Safety is certainly the most important issue. While water dams have excellent safety records, in In tailings dams, the rate of failure is higher with catastrophic impact on society and environment. Geomembrane systems can contribute to improve safety of tailings dams by preventing the partial or total saturation of the dam body.
With the same objective of safety, geomembrane systems are adopted in pumped storage schemes to prevent or stop leakage in the reservoirs and the related pressure tunnels and shafts.
Besides the technical results, gaining appreciation and confidence of designers and owners is probably the most important achievement of geomembrane systems in these 60 years. This has been possible thanks to the outstanding performance of hundreds of projects worldwide
Fig 1: Nam Ou VI rockfill dam, 2016: > 37,900 m² of Carpi exposed SIBELON® geomembrane facing installed in less than 12 weeks. Staged installation following construction of the embankment: the picture shows the geomembrane facing completed in the lowest first stage, and ongoing in the second stage
Fig 2: Concepcion RCC dam, 1991: Carpi exposed SIBELON® geomembrane system. Total leakage from > 15,600 m2 of facing is 1.9 l/s
Fig 3: Underwater installation of Carpi exposed SIBELON® geomembrane system to repair the upstream face of Studena buttress dam, 2018
Our Ongoing Projects (India)
UPPER BHAVANI MASONRY DAM
Upper Bhavani dam, a stone masonry dam of 80 m height, located in The Nilgiris District, TamilNadu (India) is the second project for Carpi in the DRIP program (Dam Rehabilitation and Improvement Project). The dam constructed in the year 1965 faced severe leakage in shaft surrounding the spillway inspite of the temporary repair solutions done between 2003 and 2010. The project is being executed in 2/3 phases out of which 20% of geomembrane installation has been completed in first phase. The next phase will commence once the monsoon ends. Despite the challenges of extreme cold weather and location of dam in deep reserved forest and threat of extremists, 80% of work has been planned to be completed in second phase. The water from the Upper Bhavani Dam acts as the main source for a series of cascaded power houses with a total power generation capacity of 600 MW. Thus saving water is of utmost importance for the client TANGEDCO (Tamil Nadu Generation and Distribution Corporation Ltd)
Recently Completed Projects (India)
SERVALAR MASONRY DAM
Servalar dam, a masonry dam of 52.74 m height, located in Papanasam, Tirunelveli District (India) is the first to be rehabilitated in the DRIP program (Dam Rehabilitation and Improvement Project). The Dam constructed in the year 1986 has deteriorated so badly that it needed an emergency long term repair solution. The leakage observed in 2014 which was more than 7200 lpm through gallery and downstream side was reduced to less than 20 lpm after geomembrane installation This remarkable reduction in the quantum of leakage has resulted in additional supply of drinking water for the public as well as irrigation purpose apart from power generation.
Mrs.Gabriella Vaschetti,
Technical Director,
Carpi Tech B.V, Switzerland,
Email : gabriella.vaschetti@carpitech.com
Mr. Jagadeesan Subramanian,
Business Manager (Technical/Marketing)
Carpi India, Chennai
Email : jagadeesan.subramanian@carpitech.com
Current Issue
12-2025
