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The ugly rivers of Southern California

Recently, I was down in Southern California to do some research in the Water Resources Collection & Archives at UC–Riverside. On the way back north, I stopped in Montebello, east of Los Angeles, to visit the site of one of the last battles of the Mexican-American War in California, the Battle of Río San Gabriel. On the afternoon of January 8, 1847, Californio forces under the command of José María Flores tried to prevent American troops from crossing the San Gabriel River as they headed toward Los Angeles. Having read about the battle beforehand, I was able to picture the site in my head: a wide, shallow river, with a sandy bottom, bordered by willows on either side.

Painting of the Battle of Río San Gabriel by James Walker. The description of the picture identifies it as the Battle of Los Angeles, which was a different battle the next day (also known as the Battle of the Mesa). But I’m almos certain that this actually portrays the Battle of Río San Gabriel, because it matches the accounts of the battle, and doesn’t match the Battle of Los Angeles, which was a running engagement. (Source: Wikimedia Commons.)

Painting of the Battle of Río San Gabriel by James Walker. The description of the picture identifies it as the Battle of Los Angeles, which was a different battle the next day (also known as the Battle of the Mesa). But I’m almos certain that this actually portrays the Battle of Río San Gabriel, because it matches the accounts of the battle, and doesn’t match the Battle of Los Angeles, which was a running engagement. (Source: Wikimedia Commons.)

What I saw instead was very different: a massive concrete channel, littered with trash but without so much as a trickle of water flowing in it or a blade of grass growing along its length as far as the eye could see.

What the Battle of Río San Gabriel site looks like now. (Note that this is actually the Río Hondo rather than the San Gabriel River; see below.)

What the Battle of Río San Gabriel site looks like now. (Note that this is actually the Río Hondo rather than the San Gabriel River; see below.)

I was surprised by what I saw, but I shouldn’t have been. Come to think of it, all of the rivers I had seen in the greater Los Angeles area were heavily engineered. The river in Montebello was a twin of the more-famous Los Angeles River (and in fact is a tributary of it). The Los Angeles River borders the downtown area and has hosted chase scenes in various movies (including Terminator 2). Looking down at the engineered river channel in Montebello, I couldn’t help but wonder:

Why are the rivers of Southern California so ugly?

When I got home, I found the answer in a book in my library. The book was The Los Angeles River: Its Life, Death, and Possible Rebirth, by Blake Gumprecht. According to the book, the flow of the Los Angeles River varied widely between the seasons. During the dry summer months, the river would be a lazy, languid stream, meandering this way and that as it flowed down from the mountains to the sea near Long Beach. But in rainy winters, the river could become a raging torrent, washing away houses, farms, animals, and people.

Los Angeles proper was not vulnerable to flooding so much as the towns up- and down-stream of the city. As the Southland developed, and buildings and pavement took over land that used to absorb rainfall, the problem of flooding got to be more acute. Attempts to deal with the problem at the local level had limited success. Then the Depression came, and the federal government took over responsibility of flood control on the Los Angeles River. After a devastating flood in 1934, the Army Corps of Engineers began to channelize the Los Angeles River and line it with concrete. (An even more catastrophic flood in 1938 highlighted the need for better flood control measures on the river.) Between 1936 and 1959, the Corps channelized almost the entire length of the Los Angeles River.

Scene from the construction of the concrete channel of the Los Angeles River, 1938. (Source: UCLA Library Digital Collections, CC BY 4.0)

Scene from the construction of the concrete channel of the Los Angeles River, 1938. (Source: UCLA Library Digital Collections, CC BY 4.0)

What about the site of the Battle of Río San Gabriel? Surprisingly, while the battle took place on the San Gabriel River, the river that flows by the site now is actually the Río Hondo, a completely different river! In 1867, before the flood control measures were built, the San Gabriel shifted its course to the east and the Hondo occupied the old channel of the San Gabriel. Flood control works on the Río Hondo and the modern San Gabriel River were built in the mid-20th century, at the same time as the Los Angeles River. The Army Corps completed the Whittier Narrows Dam on the San Gabriel River and Río Hondo in 1957.

The concrete river channels of the Los Angeles area were (and still are) marvels of engineering, but they are also ugly and obviously predate the modern environmental and beautification movements. Still, it’s hard to imagine Southern California without them, and we seem to be stuck with them for the time being.

Where was Lake Texcoco?

Much of the land occupied by the great metropolis of Mexico City was once underwater. Before modern times, the Valley of Mexico was flooded by Lake Texcoco and adjoining bodies of water. The Aztecs founded their capital city, Tenochtitlán, on an island in the lake in 1325. Two hundred years later, Spanish conquistadors were astonished by the scale of the city and the causeways connecting the islands of the lake to the mainland. The Spanish conquered Tenochtitlán in 1521 and built their new colonial capital, Mexico City, on its ruins. Over the following centuries, engineers built drainage works to control the floods and eventually drain the lake almost completely. (A monument to one of these engineers, Enrico Martínez, stands next to the city’s cathedral.) All that is left of Lake Texcoco now is some marshland near the international airport on the east side of the city. Some canals on the adjoining lake to the south, Xochimilco, have also survived.

Monument to Enrico Martínez, one of the engineers who built drainage works on Lake Texcoco.

Monument to Enrico Martínez, one of the engineers who built drainage works on Lake Texcoco.

Some of the marshy remnants of Lake Texcoco, as seen from a flight out of Benito Juárez International Airport.

Some of the marshy remnants of Lake Texcoco, as seen from a flight out of Benito Juárez International Airport.

One of the surviving canals of Lake Xochimilco, a popular place for boat-rides in southern Mexico City.

One of the surviving canals of Lake Xochimilco, a popular place for boat-rides in southern Mexico City.

Where exactly was Lake Texcoco? When I have visited Mexico City, I have wondered what parts of the city were above-water (islands or lakeshore), and what parts are reclaimed lakebed. I thought that someone must have made a map of the modern-day city with the outline of the erstwhile lake superimposed on it, but I was not able to find one. So I made my own.

For the modern city, I used a 1:250,000 sectional chart that was jointly issued by the governments of the United States and Mexico in 2000. (It is part of the maps collection of the Perry-Castañeda Library of UT–Austin.) This map was a good find because it is big enough to cover the entire basin once flooded by the lakes, but it is detailed enough to include contour lines. For the outline of the lake, I used a map from Wikimedia Commons.

Map of the Valley of Mexico ca. 1519.

Map of the Valley of Mexico ca. 1519. (Source: Wikimedia Commons, CC-SA 4.0.)

I initially tried superimposing the lake map directly on the sectional chart, but I was never able to get the geographical points to line up. My second attempt (and this was successful) was to hand-draw the outline of the lake onto the sectional, using surviving Aztec place-names and contour-lines for reference. (I also had to use some guesswork.) Here is the result:

Map of Lake Texcoco and adjoining lakes superimposed over modern-day Mexico City.

Map of Lake Texcoco and adjoining lakes superimposed over modern-day Mexico City.

The map with the lakes labeled.

The map with the lakes labeled.

Some observations from this exercise of historical mapping:

  • A considerable portion of the erstwhile lakebed, including land to the east of the international airport, is still not built-up.
  • The marshes near the airport must have been the lowest part of the lakebed.
  • The western edge of the modern urbanized area, including such Aztec place-names as Chapultepec, Mixcoac, and Coyoacán, was on the western shore of the lake and thus was never underwater—except during floods. (Rule of thumb: places with Aztec names were at least partly above-water.)
  • But much of the city was underwater, including the most modern parts where there are high-rise buildings (Zona Rosa).

Now that I have made this map, I would like to see a detailed view of the territory around Tenochtitlán, which corresponds with the area around the Zócalo. Where exactly were the islands that the city was built on? But making such a map is a project for another time (and possibly another person as well).

Riding the meter-gauge rails

Broad-gauge (left) and meter-gauge (right) trains at Jaipur Junction.

Broad-gauge (left) and meter-gauge (right) trains at Jaipur Junction.

When private British capital first started building railroads in India in the mid-nineteenth century, the lines were built in broad gauge. With a spacing between the rails of 5 ft 6 in, this was, and still is, the widest rail gauge in common use anywhere in the world. The colonial Government of India started to build their own rail lines in the 1870s. These public-sector railways were more cheaply built than their private counterparts, and they were made in meter gauge (3 ft 3 3/8 in).

Even after independence and the nationalization of the private railways, broad-gauge and meter-gauge lines continued to be developed in parallel with each other. Only in the 1990s did the Indian Railways start to convert meter-gauge lines to broad gauge, under Project Unigauge. Since then, large stretches of meter-gauge lines have been replaced by broad gauge.

Meter-gauge lines survive here and there. One such line runs between Jaipur Junction and Sikar, 107 km (66 mi) to the northwest. Meter gauge used to run all of the way to Churu, another fifty miles to the north, but that stretch has recently been closed for conversion to broad gauge. (The time table posted in Jaipur Junction station still says Churu on it, although the name has been whited out and replaced with Sikar.) Someday the Jaipur–Sikar line will also become broad gauge. But in the meantime, seven meter-gauge trains will continue to run back and forth between Jaipur and Sikar every day.

Since meter gauge won’t be around forever, I felt obliged to ride the Jaipur–Sikar train when I had the chance. A month ago, I rode one of these trains from Jaipur as far as Chomun, one-third of the way to Sikar. The meter-gauge tracks at Jaipur Junction station are on the north side of the broad-gauge lines, so the tracks don’t have to cross each other. I found a place where both gauges run side-by-side, showing the difference in size.

Comparison of meter gauge (left) and broad gauge (right).

Comparison of meter gauge (left) and broad gauge (right).

The meter-gauge train was smaller and, I dare say, cuter than the broad-gauge trains I am used to seeing. Inside, the coach was just wide enough for a bench seating four or five adults.

Meter-gauge locomotive of 52083 Jaipur-Sikar MG Pass train.

Meter-gauge locomotive of 52083 Jaipur-Sikar MG Pass train.

Meter-gauge luggage car.

Meter-gauge luggage car.

Panorama of a compartment in a meter-gauge train.

Panorama of a compartment in a meter-gauge train.

I sat in the coach just behind the diesel-electric locomotive, because that one was farthest along the platform and nobody else was in it at first. When the train left Jaipur station, only two other men were in my compartment. At the first stop, Dher ka Balaji, the compartment filled up. The train passed by Jaipur’s sprawl for a while, then it reached the open countryside. After several station stops that I didn’t see the name of, the train pulled into Chomun station, a nice little colonial Public Works Department structure.

The single platform of Chomun Samod station.

The single platform of Chomun Samod station.

Glimpse of the facade of Chomun Samod station.

Glimpse of the facade of Chomun Samod station.

At Chomun, my meter-gauge technological tourism came to an end. I returned to Jaipur by city bus.

Having ridden on a meter-gauge train, I can now appreciate how much the Indian Railways have changed since the days when the narrower gauge was more prevalent. The train I rode to Chomun just didn’t have the capacity of the much larger broad-gauge trains I have ridden in India.

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