A lifting station is often not the best solution
A lifting station is a tried-and-tested method of protecting drainage points (floor drains, sanitary facilities, etc.) located below the backwater level from backwater. It pumps the wastewater via a backwater loop, which reliably prevents water from entering the house against the direction of flow. For many, that’s the end of the matter when it comes to choosing a backflow prevention system – even though the right conditions often exist to save a significant portion of electricity and maintenance costs with an environmentally friendly hybrid solution. Before opting for a conventional lifting station, you should therefore check carefully whether your installation situation actually requires constant pump operation.
Pumps only when necessary: the hybrid lifting station
Whenever there is a gradient from the drainage points to the sewer, a hybrid lifting station can be considered as a backflow prevention measure – regardless of whether the water is greywater or blackwater. In normal operation, it uses gravity to drain water without consuming any electricity. Only in the event of backwater does it begin to pump the wastewater into the backwater loop. This means that the connected drainage fixtures can continue to be used. At the same time, the integrated backwater valve stops water from the sewer system from entering the building. Hybrid lifting stations thus combine environmental friendliness and maximum cost-effectiveness with the advantages of a lifting station.
Product selection
All products installed in a drainage system are classified as construction products and must comply with building regulations in accordance with the Construction Products Directive, the State Building Regulations and DIN 1986-100. The following methods of verification are permitted for this purpose:
- harmonised standards such as DIN EN 12050 for lifting stations or DIN EN 13564 for backwater valves
- general building authority approvals, such as Z-53.2-487 for the Ecolift backwater lifting station
- building authority approval in individual cases following a suitability assessment and consultation with the relevant authority
With regard to the scope of application, DIN 1986-100 describes only the two standardised product types: lifting stations and backwater valves. However, as the commentary on DIN 1986-100 also notes, for reasons of technical development, cost-effectiveness, but also environmental protection and the economical use of primary energy sources, it is necessary that new construction materials, components, designs and fixtures are applied and used.
In this respect, innovative solutions may also be planned and used. Their scope of application is regulated in the relevant approval or must be agreed with the relevant authority on a case-by-case basis.
Thus, three types of product are generally available for protection against backwater:
- automatic sewage lifting units with backwater loop in accordance with DIN EN 12050
- backwater valves in accordance with DIN EN 13564-1 or
- backflow prevention systems with general building approval, e.g. backwater pumping stations and backwater lifting stations
This means that, in addition to established and standardised products, innovative products are also available for project planning. In most cases, there are several options depending on the specific situation. When making the final decision, the option offering the optimum balance of safety and cost-effectiveness should therefore be chosen.
