Potable water is an essential provision that requires absolutely clean, watertight facilities to process and store it.

97% of the earth's water is saltwater stored mainly in oceans. Less than 3% is freshwater, and less than
1%
is liquid freshwater for people.¹
Around half of the global population, an estimated
4.2 billion
people, had access to safely managed sanitation services in 2020.²
More than
200 million
people spend over 30 minutes daily to get water from a safe water source, most of them are women and children.¹

The waterproofing of reservoirs and tanks containing potable water must be:

  • Watertight over long periods
  • Easily maintainable
  • Food safe
  • Harmless to health

 

 

Drinking Water Facilities by Region

Pie chart graphic showing breakdown of drinking water facilities by region

Waterproofing Products and Systems for Water Treatment Tanks & Reservoirs

Interior of public drinking water reservoir in Offenberg Germany with Sikaplan waterproofing membrane

 

Sika waterproofing products used in potable water reservoirs and tanks comply with the strict regulations of public water authorities. The food and beverage industry relies on the high performance of Sika waterproofing systems in their process water tanks.

As the global leader in providing structural waterproofing solutions, Sika has the most complete, comprehensive range of products and systems. They are designed and can be adapted to meet the specific needs and requirements of owners of water reservoirs, architects, engineers and contractors on site.

Types of Water Reservoirs

Tanks
Illustration showing type of water tank reservoir above ground tank
Towers
Illustration showing type of water tank reservoir above ground tower
Tanks
Illustration showing type of water tank reservoir below ground tank
Caverns
Illustration showing type of water tank reservoir below ground cavern

Typical Exposures and Tips for Design of Water Tanks

There are many factors that may affect the degradation of water tanks and structures in water treatment plants. By understanding the cause of damage, you can better know how to treat it, repair it and prevent it from long-term deterioration. These are the most common exposures affecting water storage areas.  

 
General Considerations for Design and Specification
  • Durability and water-tightness
  • Exposures, site conditions and ecology
  • Easily maintainable
  • Food safe and harmless to health
  • Compatibility of systems
  • Life cycle costing

Water Tanks Waterproofing Solution Overview

Illustration of Sika bitumen and sheet membrane waterproofing on external below ground structure or water tank
Sika illustration of concrete water tank below grade with White Box concept waterproofing
Sika illustration of concrete water tank below grade with Sikalastic liquid applied waterproofing
Illustration of Sika waterproofing and concrete repair on external below ground structure or water tank

1. External Waterproofing for Water Tanks

To keep drinking water in below-ground storage tanks clean, it has to be protected from groundwater entering the structure.

Fully-bonded polymeric sheet membrane

Sika Solutions

Hot air welding application of SikaProof® A+ fully bonded waterproofing membrane

SikaProof® A+ pre-applied, fully-bonded TPO membrane
SikaProof®-808 pre-applied, fully-bonded TPO membrane

Bituminous membrane

Sika Solutions

Man applying wet applied bitumen membrane adhesive with trowel on below-grade wall

SikaShield® W pre- and post-applied, wet-bonded bitumen waterproofing membrane, self-protected by a cross-laminated HDPE film
Sika® Igolflex® bitumen based liquid coating

Application of Sikaproof waterproofing membrane on below ground structure

2. Concrete Solutions for Reservoirs

The Sika Watertight Concrete System offers a comprehensive solution for watertight structures. The system consists of concrete that has been specially modified with Sika admixtures to produce waterproof concrete and carefully selected waterstops for construction and movement joints. Watertight concrete structures can be designed to keep water in or out, or both.

Waterproofing admixture

Sika Solution

Concrete ready for spraying

Sika® WT-200 P Crystalline powder

Joint sealing

Sika Solutions

Sika waterbar water stop applied in poured concrete with rebar reinforcment construction site

Sika Waterbar® PVC and TPO waterstops for construction and expansion joints
SikaSwell® A hydrophilic swelling profile for construction joints
Sikadur-Combiflex® SG post-applied, bonded tapes for construction and expansion joints

Sika Combiflex waterproofing tape at water tank concrete

3. Internal Waterproofing and Protection

Sika provides a wide range of different waterproofing systems and solutions. The selection of the best system for a specific project depends on many factors, including local water conditions. The most suitable waterproofing system depends on the nature of the reservoir structure and the water quality.

Waterproofing mortars

Sika Solutions

Sika Sikalastic spray applied waterproofing for water tank construction with workers

SikaTop®-107 Seal two-component, polymer-modified rigid waterproofing and protection mortar
Sikalastic®-1K single-component, polymer-modified waterproofing mortar with crack-bridging ability
Sika®-110 HD single-component DVGW-approved waterproofing mortar without polymers

Multi-layer epoxy resins

Sika Solutions

Sika Sikagard waterproofing for water tank construction with scaffolding and workers

Sikagard®-62 epoxy resin with WRAS approval, rigid coating or reinforced multi-layer system with crack-bridging ability
SikaCor®-146 DW epoxy resin with DVGW approval, rigid coating or reinforced multi-layer system with crack-bridging ability

Hot-spray membranes

Sika Solutions

Sika Sikalastic 840-ES spray applied waterproofing for water tank construction with worker on scaffolding

Sikalastic®-840 ES two-part, elastic, 100% solids, very fast curing and colored pure polyurea liquid applied membrane with good chemical resistance and WRAS drinking water approval
Sikalastic®-836 DW two-part, elastic, 100% solids, very fast curing and colored pure polyurea liquid applied membrane with good chemical resistance and WRAS drinking water approval

Sheet membranes (TPO)

Sika Solutions

Sika blue waterproofing membrane on water tower foundation construction in Belgium

Sikaplan® WT 4220 polyolefin flexible homogeneous smooth sheet membrane with a glass fiber reinforcing inlay, WRAS approved for potable water, thermally welded
Sikaplan® WT 4300 polyolefin flexible homogeneous smooth sheet membrane with a glass fiber reinforcing inlay, thermally welded

Sika spray applied blue waterproofing at water tank

4. Concrete Repair

When there is loss of water in reservoirs or tanks due to localized damage in the rigid waterproofing system, the appropriate repair must be done. It should be compatible with the waterproofing system, whether watertight concrete or lined with waterproofing mortar layers.

Concrete spalling

Sika Solutions

Man spraying mortar

Sika MonoTop®-1010 one-part, cementitious, polymer modified coating material used as bonding primer and reinforcement corrosion protection
Sika MonoTop®-4012 cementitious R4 concrete repair mortar containing recycled waste materials

Repair injection

Sika Solutions

Injection for crack sealing

Sika® Injection-201 CE two-component PU injection resin with drinking water approval
Sika® Injection-306 three-component injection resin based on acrylate for waterproofing cracks and joints into structural concrete

Joint sealing

Sika Solution

Sikadur Combiflex waterproofing tape being applied with hot air welder at concrete joint in Glattbrugg, Switzerland

Sikadur-Combiflex® SG post-applied, bonded tapes for construction and expansion joints

Waterproofing mortars

Sika Solutions

Sika Sikalastic spray applied waterproofing for water tank construction with workers

SikaTop®-107 Seal two-component, polymer-modified rigid waterproofing and protection mortar
Sikalastic®-1K single-component, polymer-modified waterproofing mortar with crack-bridging ability
Sika®-110 HD single-component DVGW-approved waterproofing mortar without polymers

Injection for crack sealing

See Some of Sika's Past Potable Water Projects

Sika Combiflex waterproofing tape at water tank concrete
Image: Reservoir in Dupail, France: 900 m of Sikadur® Combiflex® SG Tapes
Sika Sikalastic spray applied waterproofing for water tank construction with workers
Image: Rapid refinery in Pengerang, Malaysia: Tank refurbishment with Sikalastic®-1K (spray application), Sikadur® Combiflex® SG Tapes and Sikaflex® PRO-3
Sika Sikagard waterproofing for water tank construction with scaffolding and workers
Image: Desalinated potable water storage tank in Al Khobar, Saudi Arabia: 90,000 m2 of Sikafloor®-161, Sikagard® PW
Sika blue waterproofing for water tank with ladder in Oman
Image: Drinking water tank in Oman: Multi-layer - Sikafloor®-161, Sikagard ® PW in blue color
Sika Sikalastic 840-ES spray applied waterproofing for water tank construction with worker on scaffolding
Image: Basin in San Esteban, Spain: 800 m2 of Sikafloor®-161 and Sikalastic ®-840 ES
Sika Sikalastic 840-ES spray applied blue waterproofing for water tank construction with worker
Image: Reservoir in Santa Cruz del Valle, Spain: 1,800 m2 of Sikafloor®-161, Sikalastic®-840 ES
Sikaplan waterproofing membrane on water tower construction in Mexico
Image: Water tower in Leon, Mexico: Sikaplan® WT-4220
Sika blue waterproofing membrane on water tower foundation construction in Belgium
Image: Water tower in Beersel, Belgium: Sikaplan® WT-4220
World Map Light Grey

Contact Us

Our product solutions and project support provide: 

  • Single point of contact for all product technologies and access to the Sika network 
  • The best fit solutions for your specific applications 
  • Complete solutions from roof to basement 
  • Specification and detail development support 
  • Local building codes, standards and practical application knowledge 
  • Sika specialized and certified contractor network 
  • Expert technical assistance throughout your project

¹Source: Swiss Agency for Development and Cooperation SDC

²Source: UNICEF State of the World's Sanitation report 2020