Automatic pool covers in L’Ametlla de Mar

L’Ametlla de Mar has 2,342 pools on the Land Registry

According to the Land Registry there are 2,342 uncovered pools recorded in L’Ametlla de Mar — the municipality appears in the file as “Ametlla de Mar, L'” — 87 more than in 2022, when there were 2,255: growth of 3.9% in four years. That figure makes it the fourth of the 184 municipalities in the province of Tarragona, behind El Vendrell (2,807), Calafell (2,802) and Mont-roig del Camp (2,614), and ahead of Cambrils (1,837), Tortosa (1,718), Cunit (1,582), the provincial capital, Tarragona (1,533), Roda de Berà (1,321), El Catllar (1,270) and Reus (1,125).

The province comes to 41,968 pools and has gained 1,825 since 2022, 4.5% more. Catalonia has 204,648 pools across 936 municipalities: Barcelona leads with 108,322, Girona records 46,007, Tarragona is third with those 41,968 and Lleida closes the list with 8,351. On the Spanish map, Madrid is the first province with 147,555, Alicante the second with 132,495 and Málaga records 83,789.

What is interesting about L’Ametlla de Mar is not the absolute volume but the density. The provincial average works out at some 228 pools per municipality, so this municipality packs more than ten times that average into 66.87 km²: around 35 per square kilometre and around 31 for every 100 residents. That ratio is the fingerprint of the settlement pattern the census describes: 8,286 homes, of which 5,238 are not a main residence, spread along the coast in estates of detached houses and holiday apartments.

A necessary word about these numbers. The Land Registry census under-records: it is a floor, not a ceiling. Some pools are never declared and others are entered late, so the real figure is higher than the published one. The Land Registry also makes no distinction between a private pool, a communal one and a campsite pool: those 2,342 are every body of water in the municipality, not 2,342 houses with a pool. And the figure does not break down below municipality level: there is no split by village or by estate, so nobody can say how many there are in Calafat and how many in Les Tres Cales. When we divide the area up we do it by geography, never by pinning numbers on one neighbourhood.

In practice, that profile of a family pool on its own plot is the one a cover pays for itself on fastest. Closed, it cuts evaporation by between 70% and 80%: in an 8×4 metre pool, between 15,000 and 25,000 litres a year you do not have to replace. The other reason people call us is safety: closed, the slats form a continuous surface that keeps anyone out of the water and holds 100 kg, built to the NF P90-308 standard, a French standard, not a European one. That does not make it a walk-on or walkable surface. You can see the whole province on pool covers in Tarragona and the region as a whole on pool covers in Catalonia.

Mestral, salt air and a house shut up: what this coast asks of a cover

Let us start with the wind, because on this stretch of the Ebro coast it is the first thing that comes up in any conversation. The characteristic wind in L’Ametlla de Mar is the mestral, the north-westerly, the same one that rules the whole Baix Ebre and the country around the delta. It blows off the land: it comes in from inland, drops down the flank of the Montagut and runs out to sea across the coastal estates and the town itself. Every plot has its own exposure depending on where on that slope it sits and which way it faces, and that is something we look at on the day we come to measure. It matters for two reasons: evaporation, because air sweeping across the water is, after the sun, the great driver of water and heat loss; and what the wind brings with it, because with the cover closed the leaves, the pollen and the grit stay on top and come off with a hose, instead of ending up on the bottom and in the filters.

The second thing is salt, and here it is all but unavoidable. The municipality has 16 kilometres of coast and three working harbours: the Port de l’Ametlla de Mar, run by Ports de la Generalitat, with a fishing fleet, a marina area and the Club Nàutic; the Port Esportiu Marina Sant Jordi, at Sant Jordi d’Alfama; and the Port de Calafat. A good many of the pools sit a few metres from the cliff, with the sea breeze hitting the terrace full on. That is why the whole structure, the shaft, the brackets and the fittings are AISI 316L stainless steel, the molybdenum-bearing grade made for marine air, and why we never use aluminium. Maintenance is next to nothing: rinse the slats, the shaft and the brackets with fresh water. There are no rails or guides to grease, because the slats float on the water.

The third thing is water. No river crosses the municipality: the Ebro lies outside it. What there is instead are seasonal ravines and torrents that come down off the slope and empty straight into the sea — the barranc del Calafat, the Calafató, Calallisses, Sant Jordi and Calaforn, plus the torrent del Pi north of the town and the torrent de Santes Creus. They run dry most of the year and let go all at once when they do run. For a pool that means two things: every litre in the pool is worth looking after when it does not rain, and it is worth having the water covered when dirty water comes down off the slope.

The fourth thing is what lands in the pool the rest of the year. The southern front of the municipality is protected land: the “Cap de Santes Creus - Litoral meridional tarragoní” site is listed in the PEIN, Catalonia’s Pla d’Espais d’Interès Natural, and forms part of the Natura 2000 network under code ES5140001. Within this municipality it has two areas: the Cap de Santes Creus, which follows the coast as far as the natural harbour of l’Estany, and the mouth of the torrent del Pi, north of the town, a wetland with the standing of a wildlife reserve, because it holds an established population of fartet, Aphanius iberus. Inland, the municipality is dry-farmed olive and almond country. Having that landscape next door is part of what the plot is worth, and also the reason the bottom of the pool gets dirty: leaves, pollen and fine soil end up in the water every time the wind blows off the land.

And the fifth thing is the household calendar. With 5,238 of the 8,286 homes not a main residence, many pools go half the season with nobody in front of them, and a closed cover leaves the pool covered and shut to access through those months: it is what we are asked for most in Calafat, Les Tres Cales and Sant Jordi d’Alfama. With one safety warning we always repeat: the cover has no alarm and no obstacle sensors, and it does not stop on its own. It has to be operated with the pool in view and nothing on top of it, and you must never pull the slats by hand.

Given all that, choosing the slat is not a matter of taste. PVC is the robust option, in four shades: white, beige, grey and blue. Solar polycarbonate lets the sun through and warms the water underneath, 6 or 7 °C over the day with no energy cost, and comes in seven shades: blue, royal blue, platinum, green, smoke, royal black and royal grey. Transparent polycarbonate, in transparent, platinum and blue, is the one that looks best on pools with a view over the Golf de Sant Jordi. We set it all out, with sections and weights, on slat types, and the roller systems on cover models. What we do not make is walk-on covers, telescopic covers, enclosures, domes, winter tarpaulins or thermal blankets: only automatic slatted covers, and we have done since 2005.