One reach of river they left alone

In the 1930s, Los Angeles County poured its rivers into concrete, and the Arroyo Seco went into the channel like the rest — except for one reach in Pasadena, where the pouring stopped. The lower arroyo was left unlined. The streambed there still runs on gravel, and it is the only stretch in the city where the water sounds like water.

Walk down the morning after rain. The sound reaches you at the rim — irregular, soft-edged, nothing like the smooth hiss of water on concrete — and the walk down is a walk into it. The birds are there for the unlined banks. The cool air pools against live ground. The city above the rim goes to rumor.

Everything good about this half mile follows from a single omission, made ninety years ago, reach by reach, by people who could have poured it and did not. A river, it turns out, was never a fact of geography here. It was a decision — and in one place, the decision went the other way.

Stand at the water and listen for what the rest of the city traded.