Case study areas

The central area of the Graminhais Plateau, with its highest point at 947 m, is home to the largest area of peatlands on the island of São Miguel, covering more than 100 hectares. Included in the Pico da Vara/Ribeira do Guilherme Special Protection Area (part of the Natura 2000 network) and the São Miguel Island Natural Park, the peatlands of the Graminhais Plateau can be considered a unique habitat at the national level, due to their importance in terms of biodiversity as natural water reservoirs and pioneer area in restoration actions.

In the past, due to their use as grazing land and the introduction of invasive species, the peatlands were in an advanced state of degradation. The main effects of these impacts were the alteration of the water dynamics of this ecosystem, affecting its water retention capacity, and the loss of native biodiversity. Between 2009 and 2013, 75 hectares of this habitat were restored on the Graminhais Plateau by restricting grazing in the area and implementing measures to promote water retention and control invasive plant species to restore the functionality and ecological structure of the peatlands.

Recently, the peatland has again been the subject of ecological restoration actions, using nature-based solutions (NBS) to restore this ecosystem's sponge effect. The actions undertaken are being monitored to assess their impact.

The peatlands of the Xistral Mountain are located in the northwest of the Iberian Peninsula. They belong to the Natura 2000 Network, ZEC and Biosphere Reserve. It is classified as the most valuable peatland area for conservation in the Iberian Peninsula. It is the most extensive area of peat bogs to be found on the Peninsula and has all the typologies, such as blanket and raised bogs. In addition, the headwaters of the rivers Landro, Ouro, Eume and Masma are located there. 

The Xistral Mountains exemplify very well the functioning of a mire and its sponge function. There is an area of well-preserved peatland and an area of degraded peatland. These will be used to test the different approaches in the framework of the SpongeBoost project. It was a little-studied and little-known habitat because it was considered a poorly exploitable territory. A major effort has now made it possible to carry out a systematic inventory and classification, as a preliminary to the implementation of conservation and management strategies. They are currently threatened by the installation of wind turbines, although efforts are being made to prevent their installation and avoid their effects.

The middle section of the river Ebro flows through a flat valley surrounded by mountains. In this section, it is highly urbanised, so that, in episodes of heavy rainfall, the water ends up causing major flooding and enormous damage. The biggest floods occurred in 2015, 2018 and 2021 and caused damages of about 100 million euros every ten years. The main causes are the loss of river space (50% in 100 years), massive channelisation of the river and the occupation of flood plains. To address this situation, a Life project began in 2021, the Life Ebro Resilience, under which restoration actions are being carried out to reduce the risk of flooding. The actions include the implementation of the Flood Risk Management Plan (PGRI) and the National Strategy for River Restoration and are based on intensive public participation processes with stakeholders and the local population. Through the SpongeBoost project, hydrological connectivity assessments will be carried out by measuring water infiltration and water retention in restored and unrestored sites. Surveys will be conducted to understand the effectiveness of NbS and how it can be applied as a business model.

The Eifel region stretches over Belgium, Luxembourg and Germany and consists of mountainous areas that are mostly covered in forest and moor. Large parts of the region are protected as national and nature parks. In addition to that, the northern part of the Eifel is characterised by several artificial dams that facilitate drinking water supply as well as flood protection and drought mitigation for the area. The High Fens are one distinct area within the Eifel region that is known for their moors and their intensive retention potential. Apart from that, there are ongoing questions about how important the forests in the Eifel are for water retention and how their contribution to retaining water can be boosted further.

The Weiße Elster has its source in the Czech Republic and crosses the border into Germany after just 10 km. Its upper reaches stretch through the Vogtland low mountain range into the Central Saxon Loess Hill Country, and thus into the North German Plain. Projects such as "Wilde Weiden" aim to create extensive pastureland and reintroduce Galloway herds in order to promote biodiversity and restore natural processes. After flowing for around 200 km, it crosses the city of Leipzig. Leipzig's alluvial forest is one of the largest in Central Europe and faces numerous challenges resulting from anthropogenic interventions and natural fluctuations in the environment. Human activities have strongly influenced the stream and its surroundings. Centuries of straightening, deepening, canalization and dyke construction have altered its natural flow patterns. In addition, open-cast mining has resulted in the complete destruction of the floodplain, which has exacerbated the fragility of the ecosystem. The "Lebendige Luppe" project was launched 14 years ago and focuses on protecting and revitalising the riparian forest by raising the groundwater level and restoring regular ecological flooding. With extensive hydrological and ecological datasets and an interesting mix of land use and stakeholder interests, this area was selected as the main case study site of the catchment.

The Pärnu river flows through the southwestern part of Estonia, having a catchment area of about 6714 square kilometres. The river flows from Pandivere upland in Northern-Estonia to the Liivi Bay and the Baltic Sea in Southwestern Estonia passing through the city of Pärnu situated in its mouth.  The middle and lower course of the river flows through the lowlands of Middle and Western Estonia, where conditions have favoured the evolution of peatlands. While there are many peatlands in the catchment, the area is heavily drained for forestry, agriculture, and peat production. The remaining peatlands are mostly raised bogs, while the vast majority of fens and transitional mires have been drained and degraded, and thus, the water retention capacity of the catchment is seriously affected.

The Alam-Pedja Nature Reserve in southern Estonia is an area characterised by large peatlands, wet forests, and winding rivers with their floodplains. The area of the Nature Reserve is 34 396 hectares. Several rivers flow through the area, the main ones being the Emajõgi, Pedja, and Põltsamaa rivers. After spring thaw and heavy rainfalls, the floodplains of these rivers, especially river Emajõgi, are flooded. While being in relatively good shape, a considerable amount of the floodplains are still affected by artificial drainage. Some restoration works have been carried out in the past. However, further actions are being planned, which necessitate prerequisite information about the overall water movement and potential retention capacity of the landscape and knowledge about the best reclamation practices.