Where Ibiza's water comes from.

Rain in a short season

Ibiza takes its rain in a short season. Most of it falls between October and April, often in a few heavy storms that run off the surface before the ground can hold it. The rest of the year is dry, and the dry months are the ones when the island fills with visitors. There are no rivers running through the summer, only torrents that carry water for a few days and then settle back into stone.

That shapes what a visitor notices on the island. Cisterns and wells are part of the older architecture, cut into rock and roofed against the sun, and dry stone walls still mark the fields they once protected. Ibiza has always lived on water it stored rather than water it could count on. Planning a stay here is not an exercise in denial; it is a matter of knowing where the water comes from and how quickly a dry spell turns into a difficult summer.

Under the limestone

Under the island, in the cracks and hollows of the limestone, sit the aquifers that have supplied Ibiza for centuries. Rain soaks down through the rock and gathers above a layer it cannot pass, and wells and boreholes draw on that store through the summer. An aquifer is not a tank that refills on demand. It takes a wet autumn and a slow winter to recharge, and a single dry year is felt for several.

Near the coast the balance is delicate. Fresh water sits above denser seawater in the rock, and if too much is pumped out too quickly, salt moves in and the well turns brackish. Once that happens, a season of waiting does not fix it. Wells across the Mediterranean have been abandoned for exactly this reason, and the ones that remain on Ibiza are watched more closely than they were a generation ago, with meters, inspections and, in dry spells, limits.

Desalination and the peak

Desalination does much of the heavy lifting in summer. Plants on the island turn seawater into drinking water and feed it into the same network that serves taps, showers and pools, and the water is tested before it arrives. The process is reliable, and it is not free: it takes energy at exactly the moment demand is highest. The water in a glass in August has a history of pumping, filtering, treatment and testing.

Demand climbs with the season. Hotels open, villas fill, gardens are watered and pools are topped up, and the number of people on the island rises sharply for a few weeks. That peak lands in the driest part of the year, which is the awkward fact underneath most water planning on Ibiza. Storage, treatment and restraint carry the island through the summer, and there is no river to fall back on when they do not.

Summer water is not a given here; it is pumped, treated and paid for.

A base at Santa Eulària

Santa Eulària sits on the east coast, at the mouth of a river that only occasionally reaches the sea. The town works year-round, which matters on an island where much of the tourist economy closes roughly from November to April. There is a promenade, a church on the hill above the river mouth, a bus station and enough everyday shops to make a week without a car reasonable. Buses run along the coast and inland, with more in summer.

A base like this makes the practical side of a holiday visible. Water arrives by pipe, leaves by drain and is used for laundry, ice, showers and dishes before anyone thinks about it. In August the town is full and the small uses add up across an island of about 572 square kilometres. Staying in a place that works in winter also spreads the load, and gives a visitor a reason to be here outside the peak.

Water in the landscape

The clearest water in the Mediterranean is not an accident. Posidonia oceanica, a flowering seagrass, grows in meadows from the shallows to about 30 to 40 metres and holds sediment in place, so light gets through and the sand stays where it is. The meadows between Ibiza and Formentera are part of the UNESCO listing that also covers Dalt Vila, Sa Caleta and Puig des Molins. They are a marine habitat, not a decoration.

On land, water shows up in the wetlands of Ses Salines, a Ramsar site where salt is still harvested, and in the small springs and cisterns that made farms possible before pipes arrived. The island's green is a green of drought: pines, juniper, rosemary, figs, almond trees that flower early and hold on. Rainfall decides how a year looks, from the height of the undergrowth to the colour of the fields in May.

• PosidoniaAnchoring over the meadows is regulated; use a mooring buoy where one is installed in summer.
• Ses SalinesThe wetland in the south is a Ramsar site and salt is still harvested there.
• CisternsOlder houses and farms collected rain from roofs and stored it under the ground.
• Dry stoneWalls and terraces slow runoff so rain sinks in instead of running to the sea.

Habits that help

In a hotel, the biggest lever is not the length of a shower, it is the frequency of the laundry. Towels and sheets washed daily for every room add up to a large volume of water in a place that has to make much of its own. Reusing a towel is standard practice now, and asking for a change every few days is normal rather than eccentric, and most places will oblige without comment.

Beyond that, the small things are genuinely small, but they are not nothing. A shorter shower saves a few litres; a refillable bottle saves plastic as well as water, since every bottle has water behind it. Tap water on Ibiza is treated to drinking standard, and a chilled bottle is fine. Reporting a running toilet or a dripping tap to reception is worth the thirty seconds it takes, because that leak runs all night.

• TowelsHang them up; a second use is normal and saves a full wash.
• BottleRefill from the tap rather than buying water in plastic.
• ShowerKeep it short, especially in August when demand is at its peak.
• LeaksReport dripping taps and running cisterns; they run all day and all night.

Pools, gardens and the peak

Gardens are where water disappears quietly. A lawn, a bed of thirsty flowers and a pool topped up every evening can use more in a week than a household does in a month, and much of it evaporates before it does any good. Watering at dusk, planting with rosemary and olive rather than with anything that needs constant attention, and letting the grass go brown in August are all normal on Ibiza.

Pools lose water to evaporation and to splashing, and a villa with a pool will usually have someone checking the level. In a rented villa it is fair to ask how the pool is maintained and whether the garden is on a timer. It is not a hostile question. On a dry island, a good answer tells a visitor something about how the place is run and how seriously the owner takes the summer.

At the beach and on the water

Beach showers are a small luxury with a real cost. A quick rinse to take the salt off is one thing; standing under a shower for ten minutes while the sand runs off is another. The same goes for the tap at the back of the beach used for rinsing masks and fins. Nobody is counting, which is exactly why it works better when people think about it. On an island that makes much of its water, that is not a small thing.

On the water, the rules matter more than the habits. Anchoring over posidonia is regulated by a Balearic decree, and mooring buoys are installed in some bays in summer. A seagrass meadow scarred by an anchor takes a long time to recover, and the clear water that brought the boat there depends on the meadow being intact. If a boat is chartered, the question of where it anchors and whether buoys are used is worth asking.

• Rinse brieflyTake the salt off and turn the tap off; a beach shower is not a bath.
• Mooring buoysWhere a buoy is installed in summer, use it instead of dropping an anchor.
• Boat daysAsk where the boat anchors and whether buoys are used over the meadows.

In a dry year

Some years are harder than others. When water stores run low across the Balearic Islands, the Govern de les Illes Balears and the island councils can bring in restrictions: limits on garden watering, on filling pools, on washing streets and on pressure in the network. These are announced locally and change from one summer to the next, so no guide can tell a visitor what will apply on arrival. The local town hall is the place to check.

The sustainable tourism tax that accommodation charges is meant, in part, to pay for environmental work on the islands, water infrastructure among it. The rate depends on the type and category of the accommodation and on the season; it is reduced in low season and for longer stays, and children under 16 are exempt. Rates change, so check the Govern de les Illes Balears rather than an old figure. It is the part of a holiday that connects a night in a hotel to the island around it.