Wild Lyric – Dream a wilder sound for River Liri

Increasing the technical and practical know-how of the Italian bureaucratical workflow related to dam removal and establishing a collaborative network with local authorities to make workflow easier for future dam removals in the Liri River.

Introduction

The Liri River is particularly famous for being managed by the Ancient Romans. About 110 km upstream from its mouth, the river passes what used to be Lake Fucino, separated from the lake basin by the mountain ridge of Monte Salviano. The Roman emperor Claudius had a tunnel dug through the ridge to drain the lake, which had no natural outlet, to the Liri. The later emperor Hadrian tried to improve the tunnel, but after the empire’s fall, the tunnel was not maintained, and it was blocked by silt and debris, allowing the lake to refill. A new tunnel was completed in the 1860s, and the former lake basin still drains to the Liri via that tunnel, through the ridge near the town of Avezzano.

During the Italian Campaign of the Second World War, the German defences of the Gustav Line followed the Liri valley. Now the natural habitats of the upper Liri are scattered with power plants and weirs that are making fish life harder.

Removing the barriers would improve water and habitat quality for several native fish species of economic and conservation value (e.g., Salmo trutta trutta, Gobio gobio, Squalius lucumonis, Barbus fucini, Rutilus rubilus, Telestes muticellus). The river is part of ‘Rewilding Apennines’ rewilding area and is strategic for the return of the Eurasian otter and other threatened, protected species of mammals (e.g., the critically endangered Marsican brown bear, the wolf, the wild cat, the polecat, and several ungulates) and birds.

The Liri River and its valley are also an important ecological corridor for terrestrial wildlife between the Abruzzo, Lazio and Molise National Park to the east and the Simbruini-Ernici mountains to the west.

Project context and opportunity

The ‘barrier 16’ presented in this project is one of the barriers identified as priorities for removal among 289 barriers detected in the study area and 126 in the Liri-Garigliano river catchment by a preliminary study that sampled 169 km of river stretches for barrier inventory along four rivers (Liri, Sagittario, Gizio and Sangro) (Giovacchini 2021). The same study revealed that the Central Apennines have a high density of barriers, with weirs occurring mostly in a few hotspots along the watersheds. The Liri-Garigliano catchment has the highest density of barriers.

Nevertheless, only a few (15%) of this high number of barriers were considered relevant and challenging for fish movements and, therefore, priorities for removals (Giovacchini 2021).

This dam is one of the barriers identified as a priority for removal from the preliminary study (Giovacchini 2021). It will open 9.3 km of river upstream and 1.6 km downstream, releasing habitat for several endangered fish species and other endangered and critically endangered biodiversity. The river is a priority for protected species related to EU Bird and Habitat Directive, including the otter.

Remarkably, the project will also gather relevant data on fish assemblages’ occurrence and abundance and evaluate the geomorphological aspects related to removing this and other barriers in the catchment.

The project will pave the way for other barrier removals in the same river and in the rewilding area, finally kickstarting the dam removal movement in Italy, which has stayed rather passive in this subject so far.

Project aims

Rewilding Apennines’ (RA) mission is to make the central Apennines a wilder place, using the extraordinary richness of nature to counter rural depopulation and establish enterprises that link to a wild landscape. Over time, RA has worked closely with local partners, NGOs and National Parks to improve habitat and wildlife protection in corridors that connect the main protected areas.

This project will allow RA to increase the technical and practical know-how of the Italian bureaucratical workflow related to dam removal and establish a collaborative network with local authorities to make workflow easier and quicker for future dam removals. Supporting the local NGOs involved in river protection will press institutions with a demand for new dam removals. Thus, it will be possible to replicate dam removal on other weirs in the same river to expand the magnitude of the dam removal and river connectivity.

Sharing best practices and disseminating is one of the objectives of Rewilding Europe, a partner of Dam Removal Europe: we might have the opportunity to start promotion activities with a sensational launch, as it would be the first weir removed in Italy. In this way, the Liri River can be a national case study that teaches how a river can be protected by the communities that live on its banks to preserve its high biodiversity and where the return of the otter is expected, after 50 years of extinction, for the next seasons.

Communities’ involvement

Rewilding Apennines hosted a three days seminar (“Rewilding in Italy“, from 3 to 5 November 2023) during which experts tackled the topic of river restoration in terms of safety, ecology and species reintroduction.

A webinar titled “Rivers free to flow” about river restoration on July 20^th was organized by Rewilding Apennines and held by ichthyologist Amilcare D’Orsi and environmental engineer Giandomenico Mercuri.

Also, Rewilding Apennines met local administrations and to inform citizens about the initiative and reassure people about the safety and the ecological value of the initiative. Local school “Liceo Scientifico Vitruvio Pollione” is also involved in the communication activities: one frontal lesson about river ecology and the effects of barrier removal and river restoration, and one practical activity on the field sampling the river for macroinvertebrates biodiversity.