Polski
There are many definitions and classifications of flooding. While floods vary in scale (local, regional, national), genesis (rainfall, snowmelt, storm, winter) or course (prolonged, flash), they share a common denominator – losses. The potential negative effects of flooding can include human life and health, environmental damage, cultural heritage and economic activity. That’s why each of us should be able to see if we are in danger of flooding.
Flooding – hazard and risk information
Flood issues since 2007. regulates in Europe the so-called. Flood Directive (2007/60/EC). It obliges all EU member states to plan flood protection measures and change the approach of existing flood protection to flood risk management.
In order to effectively meet the goals of the directive, a series of documents are being developed as part of the so-called six-year planning cycles. The following studies are expected to be completed during one full cycle:
- preliminary flood risk assessment – CMO – identifies areas where significant flood risk exists or is likely (areas at risk of flooding – ONNP);
- Flood hazard maps – MZPs – which identify areas that may be inundated in the event of a flood with certain probabilities (low – once in 500 years flood – 0.2%; medium – once in 100 years flood – 1%; high – once in 10 years flood – 10%);
- Flood risk maps – MRPs – that identify potential flood-related damage;
- Flood risk management plans – FMPs – documents that contain a description of the objectives of flood risk management and a catalog of measures to achieve the objectives of flood risk management, taking into account their priority.
Documents are created in a specific logical sequence. Areas historically and likely to be prone to flooding are preliminarily identified. Flood risk maps are then developed for them, which accurately indicate flooded areas. They are created based on available data (on the land surface, on existing facilities, on hydro-meteo data) and using dedicated tools (for modeling – simulations of specific scenarios). Flood risk maps are prepared for these at-risk areas, which present information useful in the event of a flood: the number of residents, facilities of special social importance (e.g., kindergartens, hospitals), areas under nature protection, facilities that pose a threat of environmental pollution (e.g., industrial plants), cultural heritage sites and information on economic activities carried out in these areas. A set of data and materials provides the basis for planning appropriate measures to reduce this threat, risk and possible damage – a set of such procedures is contained in flood risk management plans.
The Floods Directive places special emphasis on prevention, protection, preparation and public information. Knowledge of the threat and risk of flooding is extremely important, as it contributes to the rational management of areas at risk through appropriate land-use planning and the conduct of other activities and investments. According to the law, the duty to provide protection against flooding lies with the Polish Water, state and local governments, while in the face of the element, public awareness is extremely important, both at the stage of prevention (time before the flood) and during a flood event (response). In this article we would like to focus on the pre-flood stage, i.e. how to know if I am at risk of flooding and what it means.
Where can I find out if I am in danger of flooding?
The most important study that accurately indicates flood-prone areas is the flood hazard maps. Compiled by the Water Authority, they are available on their website. A dedicated Hydroportal (similar in nature to GEOPORTAL) contains a whole range of water management information, including flood risk areas: Hydroportal | ISOK.
On the site, which is a map portal, through search options, we can quite quickly find our locality or even a plot of land and see if our house, apartment, lot, their neighborhood is located in a flood risk area. We can also read out, for example, the water depth of 10%, 1% or 0.2% and find out how high the inundation level might be.
A technical, synthetic guide for the resident, investor, industry experts has been prepared by Wody Polskie and is available on the website. You can also find complete technical documentation for the user, developed by the portal’s contractor.
However, it should be noted at this point that the flood risk maps, although developed on a large scale (nearly 30,000 km of rivers in the country, area of the entire coast), depict only selected types of flooding and not all watercourses. They were developed for the risk of flooding from rivers, from the sea, and from the failure of hydrotechnical facilities – dikes or dams in reservoirs. Significantly, the maps do not present information on flooding or waterlogging caused by the impact of sewage networks, which we have faced most often in recent years. Due to the nature of this type of flooding and the division of powers between government and local government structures, the issue of rainwater management in the city, as well as protection against these phenomena, is mainly the responsibility of local government. Some cities in Poland already have relevant studies or are in the process of developing them. Meanwhile, in an effort to standardize a nationwide approach to urban flooding in the coming year, the Water Authority plans to develop a guide for identifying areas at risk from rainwater in urban areas.
I live in a flood risk area, what’s next?
I live or plan to live in a flood risk area – what does this mean for me? The ranges of areas of special flood risk (once-in-100-year flood and once-in-10-year flood) are introduced in many documents, including. to the study of the conditions and directions for spatial development of the municipality, the local spatial development plan, the municipal revitalization program, the decision on the location of a public purpose investment and in the decision on development conditions. Especially the latter document may be of interest to those who are just planning to build their dream home. It should be noted that the fact that a house or plot of land is in a special flood risk area does not always mean that no further development or construction is possible. It all depends on the level of danger (depth of flooding according to the MZP). For the lowest level of danger (inundation level of up to 50 cm), exemptions from development bans are allowed under conditions specified in the decision. Such restrictive restrictions do not apply to the flood risk areas developed in the scenario for low probability floods (once in 500 times) and floods from the failure of hydrotechnical facilities (embankments, dams). However, regardless of the level of danger, it is good to be aware of the risks involved, which is extremely important, especially when dealing with a major flood, such as those of 1997 and 2010. Through proper land-use planning, introduced development restrictions or special arrangements, flood risks can be successfully minimized and many losses avoided.
Typically, the threat cannot be eliminated completely, while dozens of different investments and activities are carried out each year to improve flood safety throughout the country. For areas identified as most at risk (problem areas), measures are planned to reduce this risk. They are listed in flood risk management plans and their subsequent updates. The latest assumptions for the river basin areas (Vistula, Oder, Pregoła, Danube and Elbe) were adopted in the form of regulations of the Minister of Infrastructure dated October 18, 2022. and will take effect on March 23, 2023. The documents are available on the website of the Ministry of Infrastructure and the PZRP project website. Also on the Hydroportal of Polish Waters, we can check whether flood control measures are planned for my area. These may include typical hydrotechnical solutions, such as the construction and reconstruction of embankments or polders, but also a range of non-technical activities (labeled “other”), including related to restoration of natural retention, construction of flood warning systems or educational activities.
Flooding – raising public awareness
By far the biggest challenge is to reach as many people as possible living in flood risk areas who are realistically at risk. During the development of flood risk management plans, nationwide information campaigns were conducted under the slogans “Flood. I’m not affected…” (2014 – 2015) and “Stop the Flood” (2020 – 2022), along with a series of activities and actions to raise public awareness of the topic. A lot of educational materials have also been prepared, specific lesson plans that can be successfully used by teachers and educators throughout the country. Building correct patterns and awareness is best started at an early age. Still, there is much to be done. In an era of advancing climate change and its consequences that are so acutely felt every year, including severe flooding and waterlogging, it is easy for each of us to learn more about the flood risk and the prevention efforts underway.
For more available information on existing planning documents or the stages of implementation of their next updates, please visit the Polish Waters’ websites: www.powodz.gov.pl and www.stoppowodzi.pl.
