Water reservoirs play a vital role as storage facilities for clean water. Any deviations in environmental conditions can jeopardise the purity and safety of the water supply. Dehumidification systems help preserve the longevity and effectiveness of reservoir infrastructure by regulating humidity and maintaining optimal humidity levels.


Water reservoirs depend on the crucial role of pumps, which are designed to be robust and constructed with durable materials to ensure reliability and longevity. However, excess moisture within water reservoirs can lead to a range of issues, including:

  • Corrosion resulting in the formation of rust on metal surfaces
  • Condensation on cold surfaces such as pipes and other equipment
  • Growth of mould and bacterial, compromising indoor air quality

  • Contamination of stored water, posing potential health risks for consumers

  • Reduced infrastructure lifespan increasing maintenance costs over time

Effectively addressing these humidity-related challenges is crucial for maintaining the safety, efficiency, and sustainability of water reservoir operations, ensuring a steady and dependable water supply.


Water reservoirs, with their large surface areas and temperature variations, are prone to high humidity levels, which can lead to several issues including increased maintenance costs. Among these challenges, condensation stands out as a significant concern. When warm moisture-laden air comes into contact with cooler surfaces, it undergoes a cooling process, leading to the formation of droplets. These droplets accumulate on structures, equipment, and surfaces throughout the water reservoir.



Cotes dehumidifiers offer an effective solution for managing humidity in water reservoirs, operating efficiently within the typical temperature range of these facilities (-15 to 35°C). With the ability to provide customised dehumidification strategies, Cotes units effectively tackle moisture control challenges on a larger scale, eliminating the need for additional ventilation systems or expensive specialised ductwork. This solution safeguards the integrity of the water reservoir and its components, ensuring a longer service life and reducing the risk of unexpected failures. Therefore, incorporating dehumidification into water reservoir management is an effective strategy for protecting production output, mitigating risks, and ensuring reliability and durability.


Located in the municipality of Oetwil am See in Zurich, the Rebrain reservoir, built in 1978, serves as an important water storage facility for the region. It has a capacity of 1000m3 for industrial reserve and an additional 200m3 designated for firefighting purposes. However, its single-chamber design presents significant challenges. A complete shutdown of the reservoir is required to carry out any cleaning or maintenance operations. Consequently, there is a pressing need for a comprehensive renovation and expansion.

To address concerns regarding equipment longevity, Cotes’ trusted partner in Switzerland, Krüger + Co. AG, , has installed a Cotes Modular C30 unit at the entrance of the reservoir, ensuring optimal conditions. The primary focus of this installation is on mitigating corrosion and safeguarding electronic components responsible for controlling humidity.



Image: Rebrain Reservoir located in the Zurich municipality of Oetwil am See


Radon, a colourless and odourless gas resulting from uranium decay in soil, rock and water, presents significant health risks, including lung cancer, particularly in regions like the Swiss Alps and Jura in Eastern France. This hazard is notable in waterworks, as increased moisture levels can exacerbate radon infiltration, posing a significant challenge.

To address the radon issue in the waterworks facility, Krüger + Co. AG installed a radon removal device equipped with a built-in timer. This device operates at regular intervals, expelling a portion of the reservoir’s air to the outside. As the expelled air mixes with the ambient air the radon concentration is diluted to a level that no longer poses a threat, ensuring a safe and healthy environment inside the waterworks.


2310_Referenzstory_Entfeuchen_Rebrain_webImage: Cotes Modular C30 unit within the reservoir


Krüger + Co. AG chose to supply the facility with a Cotes Modular C30 unit due to its compact and versatile features. Suitable for a range of water applications and general humidity management of indoor spaces, the C30's easy-to-clean design, sleek appearance, and high quality make it an ideal choice. Additionally, the C30 unit boasts low energy consumption, operates quietly with low noise levels, and requires minimal maintenance, ensuring cost-effectiveness for the facility.


  • Tailored precision control capabilities to meet the unique requirements of waterworks  facilities
  • Dehumidifiers engineered for longevity, featuring a robust design that guarantees an extended service life
  • Resilient and trustworthy dehumidifiers crafted to deliver consistent performance in demanding conditions
  • Ensures a return on investment, offering cost-effective operations and maintenance to enhance overall profitability


Cotes adsorption dehumidifiers ensure precise humidity control across a wide range of applications, contributing to optimal conditions and operational efficiency. Whether used in indoor water reservoirs or outdoor water facilities, Cotes dehumidifiers effectively manage humidity levels, enabling operators to maintain precise and controlled temperatures despite external factors, weather conditions, or other challenging application conditions.

Learn more about the Cotes C-range adsorption dehumidifiers: Download the C-range Brochure

OI_ProductImage_PartnerLineup_SteelOverlay_20210609-min Image: Cotes C-range Adsorption Dehumidifiers


Do you have issues with humidity? 

If you would like to determine the right dry-air solution for your water reservoir facility or if you would like to explore what a custom dry-air strategy can do for your business, please reach out to one of our trusted partners near you.

Find a Cotes Partner near you