What water management lessons can Mediterranean nations teach?

Whilst there has been a growing trend of extreme weather phenomena over the past decade, the summer of 2023 is when water security and water management became a topic that simply could no longer be ignored.

One country that faces the threat of water scarcity particularly acutely is Spain, which has forced the nation to revolutionise and reform its entire water system with water security at the forefront.

This reform, whilst vital for the future and beneficial in its own right, also serves as a roadmap to help Northern European nations who are starting to face unanticipated stresses to their water supplies for the first time.

As what is currently considered to be extreme weather increasingly becomes the norm, what Spain is doing now to prevent it will likely be replicated across the continent and potentially across the world.

This is similar to how in countries such as Greece and Libya that have faced unprecedented deluges and floods over the summer flood defence technologies from Northern European nations such as the Netherlands and the United Kingdom have been adopted.

Why Spain? Why now?

The country of Spain is one of the southernmost countries in Europe, and its two biggest industries are highly water-intensive.

The first of these industries is agriculture, and given that Spain is the primary supplier of fruits and vegetables to the rest of Europe, its farms are not only substantial in size but have particularly high water requirements.

Meanwhile, Andalusia in the south of Spain is a particularly popular tourist destination and home of the Costa del Sol, which is in itself one of the most water-intensive industries in the world.

This is particularly true in Andalusia, given that many tourists head towards beaches, pools and golf courses, the latter of which has particularly intense irrigation and water needs.

Many Mediterranean countries are heavily reliant on groundwater supplies naturally purified with the help of aquifer rock layers, which are permeable minerals that water pours through.

As extreme heat and drought conditions intensify, aquifers become increasingly stressed, which leads to lower quality groundwater, inefficiencies and a concentration of pollutants.

Whilst acute water stress is often managed through restrictions, it became abundantly clear that this would not be enough to ensure water security, so Spain took the opportunity to focus on more sustainable, long-term solutions.

An investment into future life

In Spain, as with many other countries, the key concern and a market of potential water stress is groundwater levels, and the lower this gets, the less this vital lifeline is available and when it reaches a critical point, emergency measures need to be taken.

The solution needs to be multifaceted, mindful of both local and country-wide factors, and provide a circular and long-term solution to avoid the use of energy-intensive contingencies.

Part of the solution involves replenishing aquifers and by extension the groundwater found underneath by using treated wastewater.

The approach they have used is to take wastewater after it has passed through the intensive water treatment plants and processes and inject it into the aquifers.

This helps the aquifers by reducing the amount of work they need to do in treating impurities, and the resulting water is additionally cleaned thanks to rock filtration, with the end product indistinguishable from groundwater that emerged from other sources.

This means that less water is lost overall and reduces the strain on agriculture, which is typically subject to strict limits during drought periods.

Similar systems are used in urban environments, with at least a quarter of the city of Barcelona’s water supply coming from treated sewage water that is reintroduced further up the stream before returning to the city’s supply.

This reduces the strain not only on groundwater sources that typically come from wells but also reduces the reliance on Spain’s alternative source of water in drought periods: desalination plants.

The process of desalination removes water from seawater and brine, making it fit for human consumption as well as usable in other applications such as irrigation and water-intensive industries.

Desalination is regularly used in areas where there is an insufficient supply of fresh water from other sources, but producing desalinated water at an industrial scale such as that needed to ensure a city the size of Barcelona has sufficient drinking water does come at a cost.

Part of that cost is the huge amount of energy required for the reverse-osmosis process, and in Spain just 42 per cent of its electricity came from renewable sources, meaning that in some cases desalination relies on natural gas to function.

This can be fixed through intensive power infrastructure investment, but the more significant concern is efficiency.

For every litre of seawater, 450ml of freshwater is produced alongside 550ml of highly concentrated salty brine.

This brine is at present returned to the sea, which can cause damage to ecosystems due to the salt affecting the water conditions and potentially harming certain types of aquatic life.

Desalination is therefore important if not vital during drought conditions, but it cannot serve as a panacea for intense levels of water stress, and the Spanish national government appears to be aware of this if their €2.2bn investment into modernising its water infrastructure is anything to go by.

A significant part of this is set to be spent building more desalination plants and improving water purification in Andalusia and other southern regions of Spain, but other parts are intended to modernise and restructure their infrastructure.

The entire sector is set to be digitalised throughout all of its supply systems, and agricultural and dairy businesses are set to be supported to help use water more efficiently.

The primary lesson to take away from what Spain has proposed and is implementing is the importance of acting in advance of a potential crisis to stop it from becoming devastating.

Desalination is an effective backstop and useful in the short and medium term to manage extreme weather, but the proof of Spain’s efforts will be in the longer term solutions to continue using treated, reclaimed and recycled water more regularly.

As well as this, whilst some may wonder about the price tag, it is essential to note that a pound spent on water security efforts is paid back at least sixfold in avoiding further and more critical measures.