Yes, water is still flowing through the Comtal irrigation ditch. What surprises me most is that it looks crystal clear. It's moving at a certain speed—which makes its sound clear (even now that the machinery for burying the R2 train line is working at full speed). If I focus my gaze on the water, I can imagine it's from a river in the Pyrenees, one of those that invites me to swim (but when I put my feet in, not so much). However, if I raise my gaze, the contrast is enormous. I'm in Montcada i Reixac, in the Can Sant Joan neighborhood, urbanized since the 1920s by both railway workers and those from the Asland cement factory. Yes, the one from "Arriving at the cement factory, left lane signposted, direct to Barcelona", which decapitated the Montcada hill to extract limestone and make cement.
Montcada is in the middle of the city, like on Thursday. A multitude of communication routes (cars, trains, metro, etc.) converge here. It's an industrial city connected to Barcelona (although it belongs to the Vallès Occidental region). And yet, it has fertile ground. The Besòs and Ripoll rivers meet, along with the Sant Cugat stream, and more streams, torrents, irrigation ditches, and fountains.
Years ago, Montcada's water was very popular: it was fresh and pure. "Barcelona doctors recommended drinking water from its springs—the now-vanished and venerated Font del Ferro, for example—because, they claimed, it had excellent medicinal properties," explains Marcel Olivé, an archaeologist and resident of the municipality who worked for many years at the Montcada Municipal Museum. He is a great enthusiast and expert on the Comtal irrigation canal.
In 1914, a fierce typhoid fever epidemic hit Barcelona. The cause was the contamination of the waters of the Mina Baixa, originating in Montcada (built in the 1920s, the Mina Baixa brought water from Montcada to the Barcelona fountains). The Barcelona City Council prohibited drinking from the Barcelona fountains that flowed from the Besòs River, marking them with a red cross. But the "goodness" of these waters, recognized for centuries, and the belief that this prohibition was driven by private interests, led many to disobey and continue drinking.
Marcel has come prepared with a stack of old photographs. He shows me one of the Besòs, from the 1970s, when this river was the Vallès dump. There's no water to be seen: everything is covered in foam. "Some people remember that when water was visible, it had a different color—and smell—every day, depending on the factory that dumped the rejected product," Marcel explains.
We began our visit at the Casa de la Mina, built in the 18th century. It now houses a senior center. Beneath the house, descending an interior staircase, you can see "where it all begins": the water that comes from the bowels of the earth, through a canal with a brick vaulted roof, where a long time ago there stood a boatman who was in charge of its maintenance. This mine, which collected groundwater from the Besòs and Ripoll rivers, replaced the traditional collection system of the Comtal irrigation ditch. Through a lock, it diverted the waters of the Besòs, a river that sometimes ran squalid and sometimes overflowed its banks (the "besosadas").
We begin the walk down the irrigation channel. For a short first stretch, the water flows through the open air. The irrigation ditch will be covered and uncovered along the way. I don't know if there's less water now than in medieval times, but God knows not even the water that flows down.
"Do you see Montcada Hill?" Marcel tells me. "It was a strategic point, the last natural barrier before entering the Barcelona plain. It's no surprise that there was an Iberian village at the top. A castle was built, the Montcada Castle. If they disagreed on any issue with the Count of Barcelona, the Montcada lords—to the Barcelonans." Having the water tap meant having power.
"The Comtal irrigation canal is the most important medieval hydraulic infrastructure linked to Barcelona. It was an initiative of Count Mir (10th century) to operate the flour mills, and also to supply water to artisan dyers and leather tanners, and, secondarily, to irrigate the fields. It wasn't until much later that people began to drink," Marcel explains to me as we walk along Reixagó Street, a pedestrian walkway that forms the backbone of the Can Sant Joan neighborhood. The Comtal irrigation canal runs just below. "The irrigation canal was a space for meeting and recreation: clothes were washed, baptisms were held, fishing was practiced... Some children from low-income families, who didn't come for the summer, learned to swim," Marcel comments. We stop in front of a section of the canal where a group of people are walking—the water reaches their knees—and there are two children wearing goggles and playing with ducks. As if they were in a cove on the Costa Brava!
We reach the Vallbona orchards in Nou Barris, generously watered by the Comtal irrigation canal. A little further on, at the Trinidad junction, the irrigation canal flows into the Besòs.
I love looking at the map of Barcelona and finding street names that have to do with water: the Torrent de l'Olla in Gràcia, the Arroyo Blanco in L'Hospitalet, on the border with Barcelona... But it's in the Ribera neighborhood where there are even more. Want to find them? The Comtal irrigation canal ran through there, and of course, the vitality of the neighborhood built by Santa Maria del Mar would have been much less vibrant without the water coming from Montcada.
A 12 kilometer medieval canal: from Montcada i Reixac to the sea
At the beginning of the 1st century BC, to guarantee the water supply to the future colony of Barcino, the authorities had to choose between taking water from the Besòs or the Llobregat. They opted for the former because extracting, channeling, and distributing the Llobregat water to Barcino required considerable elevation gains. It wasn't until 1817, with the Infanta Canal, that Barcelona began to use the Llobregat water.
Later, in medieval times, the Comtal irrigation canal was built. This irrigation canal runs for about 12 kilometers, from Montcada to the sea (it emptied at a point between the current Ciutadella Park and França station).
The first documentary reference to the Comtal irrigation canal dates back to the 11th century. However, some archaeological finds in the Plaça de les Glòries indicate that its construction could have been much earlier, around the 8th and 9th centuries. Very few sections with water remain—only the one from Moncada to Trinitat. Some have been preserved—without water. This is the case in the old Born market.