Why is Tunisia struggling to stop its beaches vanishing?

• In the Maghreb, Tunisia acutely hit by coastal erosion
• Rising seas, dams and development cited as main drivers
• Researchers say nature-based solutions are essential

GABES, Tunisia - The Tunisian coastal town of Ghannouch is home to about 600 fishermen, but early one Wednesday morning last month there was hardly a rod or boat in sight.

Fishermen say as climate change brings ever-rising sea levels, threatening the community's beaches, going out to sea is becoming tougher as rocks damage their boats and fishing nets.

"The beach sand is significantly reduced and rocks are appearing there instead," said Mohamed Ali, 39, a fisherman in the town, located about 400 km (250 miles) south of Tunis.

"I had my boat damaged several times. It is becoming difficult to go to the sea and fish," the father-of-four added.

Ali said he made about $300 per month fishing, but his income was 20% lower than in previous years before coastal erosion became a major factor.

Sassi Alaya, the head of the fisheries guild in the town's southern port, said that half of the local fishermen and about 80% of businesses - including restaurants and coffee shops - had been affected along the most eroded areas of the coastline.

"The rising sea levels and the disappearing sand have severely harmed businesses on the beach," Alaya said, with tourism experiencing a big decline over the last decade.

A combination of rising seas, overdevelopment on beaches and the destruction of natural defences like dunes, as well as the building of dams that store sand instead of letting it flow to the coast, are causing Tunisia's beaches to gradually disappear, researchers warn.

The Maghreb - made up of Morocco, Tunisia, Algeria and Libya - is more affected by coastal erosion than any region outside South Asia, the World Bank found in a 2021 study. 

Within the Maghreb, Tunisia has had the highest erosion rates in the last three decades, averaging almost 70cm a year, it found.

Accelerating climate change has also brought soaring temperatures, worsening drought and less rainfall to Tunisia, which together with rising sea levels are harming not only the country's fishing sector but its agriculture and tourism too, experts say.

Researchers at the National Institute of Marine Sciences and Technology (INSTM) said the government had responded to growing water security concerns by building more dams to save fresh water - but that has stopped sand from moving from inland to the coast, exacerbating coastal erosion.

"(Coastal erosion) is getting worse and worse because of human interference," said Oula Amrouni, a researcher for INSTM.

"People and buildings have increasingly been crowding coasts, replacing natural protections against erosion like sand dunes and wetlands," she added.

Tunisia's environment ministry did not immediately respond to request for comment about the issue.

'Socioeconomic bomb'

At least 85% of Tunisia's population of more than 12 million lives by the coast, compared to a global average of about 40%, according to the World Bank.

As coastal erosion worsens, saltwater moves inland, ruining arable areas in a "major blow to agriculture", said Gil Mahé, research director for the hydrosciences laboratory at France's Montpellier University, who is currently working at INSTM in Tunisia.

"And what about all the infrastructure built along the coast? Ports? Nuclear power plants?" Mahé added.

Nearly half of Tunisia's 670 km of beaches were acutely threatened by coastal erosion as of 2020 - a figure that has more than tripled since 1995 - according to the Tunisian State Agency for Coastal Protection and Planning (APAL).

The agency has built walls to guard the coastline against waves and sourced sand from a nearby sand quarry to rebuild beaches. In 2020 - the latest available data - it had better protected 32 km of coast.

The estimated annual cost of coastal erosion in terms of damage to land and near-shore buildings amounts to the equivalent of 2.8% of GDP in Tunisia, compared to 0.7% in Libya, 0.4% in Morocco and 0.2% in Algeria, the World Bank study found.

Yet it said the real cost to Tunisia was likely to be higher as the study did not incorporate other factors such as lost tourism revenues.

The erosion of beaches represents "a real socioeconomic bomb", Mahé wrote in a 2021 article for Montpellier University.

On the island of Djerba - about 110 km south of Ghannouch - 52-year-old fisherman Al-Akhdar Ahmed said his income from fishing had halved over the last decade - to $250 a month today - due to the shrinking beaches.

"Rocks are now surrounding about 18 kilometers of the coast of the island, destroying the livelihoods of hundreds of fishermen there," he said, adding that the presence of many chemical factories had also caused pollution affecting the sea.

Drought and dams

Three years of drought have left many of the country's 37 dams depleted or empty, and driven the government to increase tap water prices for households and companies.

Radhia Smine of Tunisia's Water Observatory last month said "it is time for the authorities to declare a state of water emergency", warning of the risk of reaching a "state of thirst".

The country is investing in building additional dams to try to store as much fresh water as possible. Economy Minister Samir Saeed last month said Tunisia was preparing studies for new dams and seawater desalination plants for development by 2025.

However, dams often trap sand and sediment that would otherwise flow to the sea, thereby fuelling coastal erosion, researchers say.

Mahé said that 80% of the coastal sand in Tunisia comes from inland.

"Dams ... (are) the major impact increasing the vulnerability of sandy coasts to erosion," he said.

Researchers Mahé and Amrouni said they were working on projects in partnerships with international institutions such as the World Bank and the United Nations' Development Programme (UNDP) to reduce erosion through nature-based solutions.

For example, one initiative - implemented by UNDP together with APAL - has installed 0.9 km of sand trapping fences and 1.1 km of palm fronds pegged to the ground to reduce the impact of huge waves on a beach on Djerba, where coastal erosion has caused heavy flooding of wetland areas.

"We want the beaches to heal by themselves through building dikes, dune fences and wave breakers using natural materials from the ecosystem," Amrouni said.

"Only in this way, can we have better beach conditions in the long run," she added.

(Reporting by Menna A. Farouk; Editing by Kieran Guilbert and Laurie Goering.)