The two actions need not be mutually exclusive and regulating rivers does not equate to 'concreting' them. Regulation and restoration can be carried out simultaneously as part of sustainable water management – although the challenges are abundant. 

For proponents of river regulation, including but not limited to water transport companies, this is a welcome measure aimed primarily at reducing unpredictable hydrological events along the river channel. On lowland rivers, and this kind is prevalent in Poland, numerous meanders form and the bigger and more winding they get the longer the water level remains low. When water levels rise and the centrifugal forces of the current increase, erosion and disruption of the shoreline occur in the meanders. It is not only inland navigation that benefits from regulatory action. If there are arable fields in the river valley, regulation prevents erosion of fertile sediments and silts. Areas valuable as animal sanctuaries are also less likely to be affected by channel migration and land erosion, say proponents of the regulation. They argue that regulating the main channel of the river does not exclude leaving old riverbeds on both banks – areas that are flooded at higher water levels and are a refuge for waterfowl and fish, together with thickets that enable nesting.  

Sceptics say

For environmental organizations, however, river regulation is a far-reaching (often too far-reaching) interference in the environment – presented as the transformation of natural floodplains by clearing riparian forests, draining wetlands, straightening and deepening riverbeds and lining banks with concrete slabs. These organisations believe that "concreting" nature leads precisely to the phenomena we would like to avoid above all: flooding.

Renaturalisation, which is generally advocated by environmentalists, is, in short, the restoration of rivers to their natural state, i.e. a meandering channel. However, proposing a complete change in the character of rivers is usually impossible, especially when the physical changes introduced by human hands are far-reaching and irreversible (and the transformations serve industry and the economy). Then the restoration would cause the human activity in question to be abandoned, which is difficult to obtain consent for.

‘By granting the status of "heavily modified" to a given body of water we in a way approve of the changes that have already been made and accept that they are necessary’ says Przemysław Gruszecki, Director of the Water Environment Management Department at PGW Wody Polskie (Polish Water Management Authority). Where there are no irreversible changes or the reason for them no longer exists, corrective action can be taken. Based on a comprehensive analysis of various parameters – from water quality and the state of the fauna and flora to the shape of the riverbed and the riparian zone, as well as the speed and degree of flow variability – we try to imagine what all these elements would look like under natural conditions, undisturbed or slightly disturbed by human activity.

Seeking balance

In accordance with the provisions of the Water Framework Directive1, which both protects water and allows it to be used in a way that strikes the right balance between the needs of man and the environment, the renaturalisation of rivers cannot (and does not have to) mean that we give up shipping or building hydroelectric power stations. Restoration can reconcile both environmental, economic and social objectives. ‘You don't restore rivers at all cost’ stresses Przemyslaw Gruszecki. 

"Restoration, understood as a set of actions whose aim (and measured effect) is to improve the condition of aquatic ecosystems, should find its rightful place in the array of management methods for rivers, lakes and coastal and transitional waters," reads the Handbook of good practices for the restoration of surface waters. It is a document prepared by PGW Wody Polskie within the task "Development of the national programme of surface water restoration". The handbook provides a comprehensive database on the preparation of restoration projects and the most common problems that may arise during their implementation. The document is available on the website of PGW Wody Polskie.

Part of a broader strategy 

The restoration programme complements other activities carried out by PGW Wody Polskie. It complements programmes such as flood risk management and drought management plans.  The planning work takes into account homogenous water bodies, i.e., river sections of similar character. The aim is to restore rivers to their natural or near-natural state where possible, while maintaining the conditions necessary for existing water uses. An example is the provision of suitable habitat and free movement for different animal species, mainly fish, according to their life cycle. By restoring the permeability of rivers, we enable migratory fish such as sea trout to spawn. The solution is, for example, to build or repair fish ladders to allow fish to travel up or down the river. It is also possible to dismantle old damming structures that no longer serve any purpose. 

The array of possible restoration measures is very wide. It includes, among other things, shaping vegetation on water banks, reconstructing a sequence of rapids (places where water flows faster) and stream pools (depressions in the riverbed between two rapids with much calmer water), preserving or reconstructing stagnant places, rebuilding (moving back) floodbanks, planting trees in the floodplain, restoring oxbow lakes, and rebuilding bank fortifications to make them more natural. These activities are carried out by PGW Wody Polskie, State Forests as well as local governments. 

‘Nowadays, rivers are no longer concreted and "straightened"’, argues Wojciech Skowyrski, Director of the Investment Preparation and Realisation Department at Polskie Waters. ‘We rely on solutions, often old and proven, which are environmentally friendly’. We use ecological materials in the preservation work, namely stone erratics and fascine, a type of wicker from the river valleys. It is made into bundles that are laid alternately with stone, which strengthens river banks. Such a structure grows over time with plants. ‘Thanks to this type of action, the water flow in the river returns to its original state’ says Skowyrski.

Renaturalisation measures have numerous environmental benefits, but their application is not always a sufficient response to existing water management problems, especially with regard to flood protection. The provisions of the Floods Directive  as well as the Water Law Act impose, inter alia, the obligation to develop flood safety solutions based on a 6-year planning cycle and to submit draft flood risk management plans (FRMPs) for stakeholder assessment in a 6-month public consultation. A multi-criteria analysis allows the most optimal set of measures to be identified, including from an environmental perspective. They are subject to evaluation by European Commission experts.

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Author: Ministry of Infrastructure

1Directive 2000/60/EC of the European Parliament and of the Council of 23 October 2000 establishing a framework for Community action in the field of water policy.
2Directive 2007/60/EC of the European Parliament and of the Council of 23 October 2007 on the assessment and management of flood risks.