The stream was culverted in 1983 and the street above it was named after an admiral. For most of the year the arrangement is invisible, which was the intention. Water that once ran between gardens now runs through a concrete pipe two metres below the tram line, and three generations have grown up on a street with no idea that it is a valley. Then it rains hard, and the ground floors of numbers 14 to 22 flood, always those numbers, never the odd side. The municipality has treated this as a drainage problem for four decades and has spent, by its own published figures, an amount that would have bought every affected flat twice over. Pumps have been installed. The pipe has been widened once and relined twice. The flooding continues, with a regularity that ought to have prompted a different question much earlier. The question is not how to move the water faster. It is what the water is doing there at all, and the answer is that it is doing what it did before 1983, along a route it has followed since the last glaciation, and that the pipe did not remove the valley. It only removed the evidence of it. Hydrologists have a phrase for this: rivers have memory. It is a metaphor, and slightly misleading, since nothing is remembering anything. What persists is topography. Water arriving on a slope will always find the lowest available line, and a culvert is not a change to the slope but a lid placed over it. The policy conclusion drawn in several European cities over the past twenty years is daylighting: removing the lid, restoring the channel, and accepting the loss of the surface that was gained. Seoul removed an elevated motorway to do it. The results are consistently better than the engineering that preceded them, and consistently more expensive to begin. What makes the argument hard here is not the money. It is that the case for daylighting requires admitting that a decision made in 1983 by competent people was wrong, and municipal institutions are not designed to hold that thought comfortably. So the pumps are serviced every spring, and the residents of numbers 14 to 22 keep their possessions above knee height, and the street continues to be named after an admiral who never saw it. The valley is still there. It has simply not been consulted.