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Deutsche Version

Step 1: Collecting Rainwater:
Roof Catchment Area

Rainwater can be collected from sealed surfaces such as roofs. Only drain roof areas, which do not release pollutants (tar, bitumen, ...).

Step 2: Filtering Rainwater:
The ecoRain Volume Filter

The fist step of a rainwater utilization plant is a filter to remove leaves on the one hand and sediments on the other hand. Filtering can improve water quality to make it suitable for laundry.
The ecoRain filter is designed for roof surfaces up to 350m² at a rainfall intensity of 300l/sxha or a maximum flow rate of 10,5l/s. The screen of ecoRain filter consists of two layers, an arrangement of coarse cascades and a fine stainless steel screen with 0.26mm mesh size to remove sediments. The cascades keep leaves away from the fine filter to avoid clogging. Pollutants are filtered out continuously and are swept to the storm sewer with small amounts of rainwater.
The system is highly effective (95%), independent of volume of water and self-cleaning. Maintenance is required only twice a year. The stainless steel filter insert is easy to remove and and an be cleaned in a dishwasher.

Step 3: Storing Rainwater:
Velocity Reduced Inlet and Concrete Tank

Rainwater is best stored underground, where reduced light and warmth ensure an almost germ-free environment. Concrete cisterns neutralize rainwater to make it useable for washing-machines.
To avoid re-suspension of fine sediments at the bottom of the cistern, the velocity of the incoming rainwater needs to be reduced. This can be achieved by increasing the diameter of the inlet pipe and diverting the flow towards the water surface.
Another important function of the inlet is the introduction of oxygen into the cistern to avoid anaerobic conditions.

Step 4: Overflow
The ecoRain Duo Siphon

The "duo siphon" is installed inside the cistern, between filter and outlet. Predetermined inlet-, outlet- and skim-off levels make it easy to install and ensures an unimpeded functioning of the system.
Once a maximum level is reached in the cistern, the siphon constantly skims-off the water surface and cleans it from floating pollutants like pollen. The two inlets are slit-shaped to increase the skimmer effect. In addition to that, the slits keep rodents away from the cistern.

Step 5: Accessing Rainwater
Top-up System and Pump

To achieve the best purification effect, the rainwater can neither be pumped from the bottom of the cistern nor from the water surface. To get the best water quality, the intake shall always be 100 -150mm below the water surface.This can be achieved by a floating skimmer.
Water is drawn via the house water supply system or via submersible pumps. As soon as water is drawn the pressure control activates and de-activates the pump automatically.Submersible pumps are silent and keep pressure constant for garden watering.
Once a minimum level is reached in the cistern, the cistern is simply topped up with small amounts of drinking water, which will generally be enough to cover the day's need.
Rainwater tank and mains water supply shall not share pipes or connections (DIN 1988).

Rainwater Harvesting