Flood protection

Flood Protection - Flood protection encompasses all structural, technical, and planning measures designed to protect buildings and properties from damage caused by flooding, heavy rainfall, and backwater, and is a key factor in determining property value, particularly for real estate located near bodies of water.

Legal Framework and Floodplains

The Water Resources Act (WHG) regulates the handling of designated floodplains in Section 78. In so-called HQ100 areas-that is, areas that are statistically flooded once every hundred years-a building ban generally applies to new structures. Exceptions are only possible under strict conditions, such as when the building is constructed to be flood-resistant and does not have any adverse effects on water runoff. Floodplains are designated by the responsible water management authorities and are publicly available in the flood risk maps and flood hazard maps of the federal states.

Owners of existing buildings in floodplains have a duty of care under Section 5(2) of the Water Resources Act (WHG): They must take appropriate measures to minimize flood damage. These include, among other things, securing heating oil tanks, storing water-polluting substances in a flood-resistant manner, and installing technical protective devices. Violations may result in administrative penalties.

The ZÜRS zones (zoning system for flooding, backwater, and heavy rain) of the German Insurance Association classify every address in Germany into one of four risk classes. Zone 1 indicates no or only a very low flood risk, while Zone 4 indicates a high risk with flooding occurring statistically more frequently than once every ten years. The ZÜRS classification significantly determines the insurability of a property against natural hazards and the amount of the insurance premium.

Structural Protective Measures

Effective flood protection starts with backflow prevention. A backflow valve in the sewer line prevents water from being forced back into the building from the sewer system during heavy rain-a type of damage that, based on experience, occurs more frequently than traditional river flooding. In addition, we recommend a pumping system for drainage points located below the backflow level, such as basement toilets or floor drains.

Waterproofing the basement against water pressure is essential in flood-prone areas. Depending on soil conditions and the groundwater level, either the so-called black tank (bituminous waterproofing) or the white tank (water-impermeable concrete, WU concrete) is used. In addition, mobile protection systems such as flood barrier systems or flood protection windows can be installed, which are activated when necessary and seal openings in the building envelope.

Anyone who owns an existing building in a flood-prone zone should also examine retention options on the property: rainwater infiltration, cisterns, and green open spaces reduce surface runoff and relieve the sewer system. Some municipalities in Bavaria subsidize the removal of impervious surfaces and the creation of infiltration areas.

Practical Tip for Nuremberg and Franconia

In the Nuremberg metropolitan region, properties along the Pegnitz, Rednitz, and Regnitz rivers and their tributaries are particularly at risk of flooding. The flood hazard maps from the Bavarian State Office for the Environment (LfU) are freely available online and should be checked before any real estate purchase. Even away from the rivers, heavy rainfall can lead to local flooding in sloped areas or low-lying areas-such as in parts of Schwabach, Lauf an der Pegnitz, or the suburbs of Erlangen.

We recommend that prospective buyers inquire with the responsible Nuremberg Water Management Office and clarify the ZÜRS classification with the insurer before making a purchase decision. This is because a lack of natural disaster insurance or insurance that is unaffordable can significantly reduce a property’s value. We are happy to assist our clients with this assessment and proactively highlight known flood-prone areas in our listings.

Frequently Asked Questions

Can I insure a property in a flood zone?

Generally yes, though insurability depends on the ZÜRS zone. In Zones 1 and 2, natural hazard insurance is generally available without issue and at market-standard premiums. In Zone 3, insurers often require higher premiums or deductibles, and in Zone 4, individual insurers may refuse coverage. However, a solution can often be found even for high-risk locations through specialized brokers or extended natural hazard coverage.

Is a backflow valve mandatory?

There is no legal requirement to install backflow valves; however, most municipal drainage regulations-including those of the City of Nuremberg-stipulate that drainage points below the backflow level must be protected against backflow. In practice, this means: Anyone who owns a basement with a floor drain or plumbing fixtures must provide backflow protection. If this is missing, the owner cannot claim compensation from the party responsible for wastewater disposal in the event of backflow damage.

How can I find out if my property is at risk of flooding?

The most reliable source is the flood hazard maps from the Bavarian State Office for the Environment, which are available online at www.lfu.bayern.de. There, you can check any address to see if it is located in a floodplain. In addition, the Environmental Atlas of the City of Nuremberg provides information on local heavy rain risks and groundwater levels. It is also worth checking the zoning plan, as designated flood zones may be listed there.

Does flood risk reduce property value?

Yes, as a rule, a proven flood risk leads to a reduction in value. The reduction depends on the ZÜRS zone, insurability, and the building’s technical flood protection status. Owners who can demonstrate that they have invested in effective flood protection measures (white tank, backflow valve, dam beam system) can limit the value reduction. Appraisers take the protection status into account when determining the property’s value.

What funding programs are available for flood protection measures in Bavaria?

In Bavaria, the state supports private flood protection measures through the “Funding for Climate Change Adaptation Measures” program. Eligible measures include backflow valves, sewage lift stations, basement waterproofing, and mobile protective barriers. Grants can cover up to 50 percent of eligible costs. Applications are submitted through the relevant district administration or the Water Management Office. In Nuremberg, measures along the Pegnitz River or in known flood-prone areas may also be supported by municipal programs-the City of Nuremberg has established its own funding pools for decentralized heavy rain prevention as part of its Climate Protection Strategy 2035. Property owners investing in a flood-prone area should always submit funding applications before construction begins, as applications submitted after the fact are generally not considered. We can help you identify the right funding programs for your property.

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