STIRLING Lloyd Polychem, a leading waterproofing technology specialist, says its high-performance products have withstood the test of time to provide effective and long-lasting protection to many water and power utility projects throughout Saudi Arabia.

For the past 15 years, the kingdom has been a key international market for the company, which has developed a range of high-performance products designed to extend the life of utility assets including substations, water tanks,a reservoirs and sewage treatment plants.

At the heart of its protective waterproofing solutions for the water and power industries – and now widely specified in Saudi Arabia and across the entire Gulf – is the company’s Permare range. Its Permare EPW and EP products retain the advantages that polysulphide and epoxy resins offer whilst overcoming their limitations to provide a high-performance coating that is easily applied, durable and flexible, says the UK-based company.

Stirling Lloyd’s marketing manager Dave Mulligan emphasises that protecting critical utility infrastructure within power plants and water treatment works is of paramount importance wherever the application.

“Many modern utility works are exposed to highly corrosive climates and environments; it is vital that such facilities remain in-service at all times with minimal shutdowns for structural repair or maintenance.

“All of the structural protection challenges encountered by the water and power industries are compounded in a country such as Saudi Arabia, where the ambitious scale of some of the civil engineering projects, combined with the harsh environment, present the most demanding conditions,” he says.

Permare EPW

Stirling Lloyd Polychem’s Permare products have been designed to afford protection to such structures. Permare EPW has been specifically developed for use with potable water to protect it from contamination or to contain it. An epoxy polysulphide, it creates a membrane with excellent physical properties, Mulligan says.

“Permare EPW is also the answer to protecting concrete from the chemically aggressive nature of desalinated water,” he says. “Flexible and seamless, it has no vulnerable joints and the strong bond it achieves to both concrete and steel is an important factor in the extended service life it offers.”

Since its first use in the kingdom in 1997, this system has been used on various water tanks and reservoir projects throughout Saudi Arabia, including sites in Buraidah, Madinah, Jeddah and Riyadh. One of the earliest, but still a flagship project today, was the High Point Reservoir, the world’s largest underground reservoir with a capacity of 3 million cu m, states Mulligan.

“Situated at the edge of An Nafud, just outside Riyadh, and a multimillion-dollar government construction project back in 1997, this underground man-made storage tank needed specialist protection due to the chemically aggressive nature of the desalinated water towards the concrete structure that stores it,” he says.

Specified by the client, Saudi Arabia’s Ministry of Agriculture and Water, Permare EPW offered the chemical resistance required, whilst also being approved for use in contact with potable water. Some 1.2 million sq m was applied and with temperatures inside the tank reaching 40 deg C and humidity up to 80 per cent during the application, the system’s tolerance to extreme climatic conditions was tested to the full.

Over the past 12 months, the product has been used to protect a number of similar projects, two of the most significant applications having been the refurbishment of a potable water tank at a filling station in Macona Street, Jeddah – a National Water Company project involving some 36,000 sq m of Permare EPW – and the ongoing treatment of basement water tanks at the Hidaya Hotel in Makkah, which has seen an area of 35,000 sq m treated.

“Meanwhile a much smaller, but no less prestigious application has been the treatment of 500 sq m of tanks at the Makkah Clock Tower, a landmark site and the world’s largest clock tower,” Mulligan adds.

“Throughout these, and other similar projects, the clients and applicators have been impressed with the Permare EPW system’s speed and ease of application. As a thixotropic, liquid-applied and seamless coating, the system is able to easily accommodate the abundance of service inlets/outlets and internal angles encountered on these type of installations as well as cope with the potentially difficult changes in profile,” says Mulligan.

Permare EP

Saudi Arabia’s sewage treatment network has also benefited from cost-effective and long-lasting protection as a result of Permare EP having been approved by several of Saudi Arabia’s regional water and sewage authorities for use on projects across the kingdom.

One of the most important sewage treatment plant (STP) applications for Permare EP has been at Buraidah, the capital city of the Qassim region. In addition to the aggressive sewage, the concrete facility is exposed to extreme weather conditions ranging from sweltering highs of 50 deg C and extremely arid summer conditions to freezing winter temperatures.

The work at Buraidah STP was split into two phases. In 2001, Permare EP was applied to the top bands of the settling tanks, aeration tanks and the exposed top bands of other structures. “Not only are these areas subjected to the aggressive climate and chemicals but also the reaction of these chemicals with the hot air meant that these dry well zones are particularly vulnerable,” says Mulligan.

In 2004, during the second phase of the works, the main contractor fully coated all the tanks with Permare EP, with some 23,000 sq m applied in total over both the phases.

Mulligan says the most significant aspect of this project, however, has been the continuous monitoring of the system to verify the high performance of the membrane. “Since Permare EP was first applied over 10 years ago, there has been no need for shutdown maintenance or repairs, ensuring the uninterrupted operation of the plant. Furthermore, when two of the settling tanks were emptied a couple of years ago, inspection of the membrane showed that after nearly a decade of service, the system was intact without any cracks or blisters,” he says.

Mulligan says despite the harsh climate and the aggressive environment experienced, Permare EP has and continues to provide effective, long-lasting protection and excellent value on a life-cycle-cost basis, on this and many subsequent water and power utility projects throughout Saudi Arabia, including on more recent projects at sewage treatment plants in Jeddah, North Jeddah and Makkah.

Stirling Lloyd specialises in the development, manufacture and application of high-performance waterproofing and structural protection membranes and systems. Its products are used extensively on global projects ranging from road and rail bridge decks and tunnels to commercial building developments, car-parks and highway maintenance applications.