Patricia Muñoz Pequeño
Sustainability Manager
Strategy, Innovation and Sustainability Division

In hindsight, sustainability reporting has undergone significant changes in recent years. Gone are the days when companies like Sacyr, with unwavering commitment and sensitivity to these issues, voluntarily provide information relevant to their ESG strategies and performance using internationally recognised frameworks, with GRI at the forefront.

With the adoption of the Non-Financial Reporting Directive (NRFD) in 2014, and its Spanish transposition in Law 11/2018, sustainability reporting became a legal obligation and, since that time, the importance of these reports has only grown.  

In 2023, with the goal of defining a clear framework for sustainability reporting that would ensure the quality of the information published, data comparability, and the consistency of the information shared by companies, the European Union approved a new Corporate Sustainability Reporting Directive (CSRD) with common reporting standards known as the European Sustainability Reporting Standards (ESRS).

But misgivings and opposition to this new regulation soon arose from the private sector; first, due to the technical complexity and breadth of its requirements and the difficulty of implementing them, highlighting the need for further clarification in certain areas, as well as greater flexibility in their application. 

Secondly, the smaller companies affected expressed doubts about their capacity to comply with this new regulation using their own resources and the potential damage that would be caused by the additional costs required for this purpose. 

The foregoing is paired with a deeper reflection on the part of the European Union; in a complex international environment facing major global changes, ensuring the autonomy, competitiveness, and resilience of the European economy without abandoning the sustainability commitments it has made, has become more crucial than ever.  

This has prompted the EU to redefine its roadmap, while keeping its ambition intact, as demonstrated by i) the strategy of the Green Industrial Deal, designed to strengthen the competitiveness of European industry while accelerating decarbonisation, and ii) the Omnibus Package, the main objective of which is to reduce the administrative burden on companies when reviewing various sustainability regulations, without renouncing the principles of the European Green Deal. 

From a reporting perspective, the Omnibus Package affects CSRD requirements as follows: 

-    Simplification of standards, reducing the number of requirements and providing greater technical clarity in their application. These texts are expected to be available in Q4 of 2025. 
-    Two-year postponement of entry into force for companies, allowing more time to adapt. 
-    Redefinition of application thresholds, excluding listed SMEs and modifying the ranges for the rest. 
-    Maintenance of limited assurance, eliminating the possibility of reasonable assurance in the future.  

In short, 2025 marks a turning point in this area, reflecting the European Union’s commitment to moving toward a more sustainable economy without jeopardising business competitiveness.  

ISABEL RUBIO ARROYO | Tungsteno

The lost city of Atlantis has captured the collective imagination for centuries. According to ancient myths and tales, this enigmatic land vanished mysteriously beneath the waves. Despite the fascination it generates and the countless theories and searches for its supposed underwater ruins, science has found no conclusive evidence of its actual existence. However, history does offer us real examples of cities that have truly been claimed by the sea.

A window into the Bronze Age under the sea

In 1967, British oceanographer Nicholas C. Flemming discovered the remains of an ancient city under the sea, near the island of Elafonisos in southern Greece. The site was identified as Pavlopetri, a settlement that is thought to date back to the Bronze Age. The following year, a team from the University of Cambridge organised an expedition to study the site. Around 5,000 years old, Pavlopetri is one of the oldest known submerged cities, with streets, buildings and tombs still preserved beneath the sea.

The prehistoric city covered 90,000 square metres and featured a complex water management system—with canals and drains, as well as a cemetery. “This neglected place in prehistoric times had occurred to be a thriving port with intense social stratification, and a lifestyle that made the Head of Investigation John Henderson to talk about the Greek Pompeii,” note the authors of a 2016 study. Several studies suggest that the city may have been submerged around 1000 BCE. Three theories attempt to explain how this happened: one suggests a gradual rise in the sea level, another a sinking of the land, and a third that a combination of earthquake and tsunami caused the city’s disappearance.

Digital reconstruction of Pavlopetri. Credit: University of Nottingham

Temples, jewels and sunken ships

In the year 2000, underwater archaeologist Franck Goddio discovered the ancient city of Thonis-Heracleion, located seven kilometres off the Egyptian coast in the Nile Delta. Founded in all likelihood in the 8th century BCE, this port city served for centuries as the main gateway to Egypt for ships arriving from the Greek world, and it was renowned for its commercial and religious significance.

The city suffered several natural disasters, and it is believed that an earthquake eventually caused it to sink beneath the sea. The European Institute for Underwater Archaeology has studied the submerged site and uncovered more than 60 shipwrecks near its ruins, reflecting the area’s intense marine activity. During excavations in 2023, researchers discovered the remains of a sanctuary dedicated to the Greek goddess Aphrodite, as well as a temple to the god Amun. They also found gold jewellery, silver artefacts, ceramics, and bronzes imported from Greece. Well-preserved wooden structures were also found, as well as ritual and funerary items, such as silver libation dishes (used for offerings poured in honour of a deity) and alabaster vessels for perfumes and ointments.

Heracleion, the ancient Egyptian port city that collapsed beneath the sea.

The "wickedest" city of the New World

Port Royal, in Jamaica, was once the most important commercial center in the New World. The town, “commonly referred to as "the wickedest city on earth", conjures images of marauding pirates, daring naval conquests, looting, riches, destruction and devastation,” according to the United Nations Educational, Scientific and Cultural Organization (UNESCO).

It began as a strategic cay used for cleaning and refitting ships when the Spanish arrived in the 16th century. Following the English conquest in 1655, it quickly developed into a fortified city and flourished as the principal commercial and naval port of the English Caribbean. Its economy thrived on the slave trade, sugar, and privateering—and it gained notoriety as a lawless paradise of alcohol, money, and sex, where one in four buildings was reportedly either a bar or a brothel.

Old map of Port Royal. Credit: The Gentleman’s Magazine / Wikimedia Commons

Excavations have revealed that beyond its many taverns, Port Royal also featured workshops, homes, and warehouses. The city stood out for its wealth and its prominence as a key center of trade and piracy in the Caribbean. In 1692, a devastating earthquake caused two-thirds of the city to sink into the sea. Subsequent fires and hurricanes thwarted any attempts at full recovery. Although Port Royal persisted as a British naval base and secondary port, it never regained its former status as a thriving hub of commerce and piracy. Today, it survives as a small fishing village in Jamaica.

At Sacyr Agua, we’re pushing the boundaries of sustainability and innovation by detecting and removing microplastics in our wastewater treatment plants (WWTP). By joining forces with Captoplastic, we are working together to make this possible.  

Although microplastic pollution (plastic particles smaller than 5 mm) occurs throughout the whole water cycle, reducing them in the treated water leaving our WWTP is a significant step in protecting the environment.

These plants are designed to remove organic matter and conventional pollutants from wastewater, but they do not normally include specific processes to deal with the wide variety of microplastics that reach them. 

“As well as becoming their preferred partner for projects in Spain, this partnership also allows us to use Captoplastic’s technology and references exclusively in markets such as Australia, Peru and Colombia,” says Eduardo Campos, Managing Director of Sacyr Agua.

An agreement built on innovation

The collaboration with Captoplastic began following a successful pilot project at the Yecla WWTP (Murcia), managed by Sacyr Agua, as part of our open innovation programme, Sacyr iChallenges. 

It was there that we discovered Captoplastic’s pioneering solution, which continuously detects and removes microplastics. This fits perfectly with our commitment to sustainability and our drive to bring advanced technologies into our business.

Pilot project success

To test and validate the technology, Captoplastic moved a demonstration pilot plant from the Cantoblanco campus of the Autonomous University of Madrid to the Yecla WWTP, where the trials were carried out.

Beforehand, a detailed study of the microplastics present in the different stages of the plant was completed, both in the water line and the sludge line. Several types of microplastics were identified, including polypropylene (PP), polyethylene (PE), polycaprolactone (PCL), poly(ethyl acrylate) (PEA), acrylic, polytetrafluoroethylene (PTFE) and polyurethane (PU). 

These microplastics were found in different forms, such as pellets, fibres and fragments, with the highest concentration in the sludge line.

The results of this first pilot trial were very positive, showing a 76% reduction in the initial concentration of microplastics. This proves the effectiveness of the solution and its potential to be scaled up.

Captoplastic Technology

Captoplastic is a Madrid-based small business dedicated to developing innovative solutions for detecting and removing microplastics. Established in 2020, the company has been recognised as a Knowledge-Based Company and works with strategic partners such as the Universidad Autónoma de Madrid and the BeAble Innvierte Kets Fund.

Its technology uses an agglomeration technique, adding an inorganic agent to the water stream so that it binds with microplastics and forms larger aggregates that can then be removed. 

Thanks to the magnetic properties of the agent, the aggregates can be easily separated and removed from the water stream. The process can handle large volumes of water efficiently. The captured microplastics can be recycled, making this a zero-waste technology that is environmentally friendly throughout its entire cycle.