Commercial Rainwater Harvesting and Treatment Systems

Treatment of water from commercial rainwater harvesting systems generally requires disinfection and filtration for many applications of the captured water. The catchment surfaces where the rainwater is collected can be contaminated by birds or materials used on the catchment surface. For example, roofing materials; different roofing materials create different levels of contamination in water that should be treated by the rainwater harvesting system.

Spartan Environmental Technologies builds integrated systems for rainwater treatment including ozone, UV and ozone/UV systems with and without filtration. Spartan can offer a single source of supply for the treatment system utilizing the technologies below.

UV Light Systems for Rainwater Harvesting

UV is a good choice for simple disinfection applications where protection of the storage tank from the formation of biofilms is not an issue. The UV system is usually positioned in the storage tank going to the application where the rainwater will be used (e.g. toilet flushing or landscape irrigation). The UV will inactivate most micro organisms present in the water. However, it will not remove any microorganisms in the tank, biofilms on the tank surfaces, or dissolved organic compounds in water. Organic compounds in the water or microorganisms living in the tank can result in color or odor problems with the water. In some applications this might not be a problem, but may be in an application such as toilet flushing.

Ozone Systems for Rainwater Harvesting

Commerical ozone systems can be positioned to treat the rainwater in the tank by recycling the water through an ozone injection system or by continuously bubbling the ozone into the storage tank. Ozone is a broad spectrum biocide that treats all of the water in the tank as well as preventing the formation of biofilms on the tank surfaces. Additionally, ozone can remove color and odors from water. This allows the water to be used in a wider array of applications.

Ozone and UV Systems for Rainwater Harvesting

Ozone and UV can be used together in a rainwater harvesting system. The ozone would treat the bulk of the water in the tanks while the UV can be used to treat the water sent to the application (e.g. landscape irrigation). This approach offers a couple of benefits:

• It provides redundancy should either system fail ensuring that pathogens never reach the end use of the water.
• For applications where residual ozone might not be desirable in the water, UV will remove most–if not all–of the ozone residual prior to the application.

Commercial rainwater harvesting systems are both economically and environmentally friendly. Using ozone and UV can safely and effectively treat water produced from rainwater harvesting applications. Rainwater purification systems have different purposes and applications, depending on the desired water quality level and the flow rate of the water needing to be collected. Please contact us for assistance and additional information on a system for your specific end use.