DUANE
Duane's take
Here's how the official marker tells it, and I'm going to do it justice. Now, if you want to talk about a gamble, talk about building something in the Texas wilderness and betting your whole mission's future on water. That's exactly what the Franciscan missionaries did when they set out to keep San Francisco de la Espada Mission alive.
They knew one thing with absolute certainty: without water, there was no permanency. So they built a dam, an irrigation ditch, and an aqueduct — and they did it in a way that would leave engineers scratching their heads for centuries to come. The dam rose eight feet above a rock ledge crossing the San Antonio River.
Two hundred and seventy feet of it. Now here's the part that gets folks — the dam curved the wrong way. Not the way any sensible engineer would design it, not the way the river seemed to demand.
The wrong way. And yet lime salts from the river gradually cemented together gravel, rocks, and layers of brush into something that held. Something that lasted.
Sometimes the unconventional answer is the right one, and those missionaries somehow knew it. The water they captured had to travel. It moved along the Espada ditch until it hit Piedras Creek, and that creek wasn't about to step aside.
So the builders kept right on going, constructing an aqueduct to carry that water over the obstacle. Construction on it ran from 1740 all the way to 1745 — five years of work in stone and mortar. And the mortar, well, tradition holds that goat's milk served as a cementing agent in the Espada Aqueduct.
Goat's milk. Which sounds like a tall tale until you realize this is the only such structure of its kind in the entire United States. For a generation, it worked beautifully.
The alluvial valley answered the water with abundance — maize, beans, melons, calabashes, sweet potatoes, cotton. Relative prosperity settled over the mission like a good season ought to. But nothing that good holds forever without a fight.
By the time the mission was secularized in 1794, only fifteen sick or aged Indians remained within its walls. The flourishing was gone. And yet the dam, the ditch, and the aqueduct survived — survived nearly a century of Indian attacks, ravaging floods, and controversy both secular and clerical.
You have to pause on that. The institution faded. The people scattered or passed.
But the water works endured. Even endurance has its limits. The ditch fell into disuse for some fifteen years before, in 1895, the newly formed Espada Ditch Company stepped in.
They repaired the dam, enlarged the ditch, changed its course, and breathed life back into something that had nearly slipped away. Then disaster threatened again. In 1941, the San Antonio Conservation Society purchased the property to ensure its preservation.
And then, in 1965, the United States Department of Interior designated Espada Aqueduct a Registered National Historic Landmark. A dam built the wrong way. Mortar mixed with goat's milk.
Five years of construction over a creek in colonial Texas. Water that fed a valley, outlasted a mission, and survived a century of everything the frontier could throw at it. Some things, it turns out, are built to last longer than the world that built them.
What the marker says
Water was vital to the permanency of San Francisco de la Espada Mission, therefore Franciscan missionaries built a dam, irrigation ditch, and aqueduct. The 270 foot dam rose eight feet above a rock ledge crossing the San Antonio River, the lime salts of which gradually cemented gravel, rocks, and layers of brush which formed the dam, regarded as an engineering feat as it curved "the wrong way". Water transported by Espada ditch crossed Piedras Creek via this aqueduct on which construction continued from 1740 to 1745. According to tradition, goat's milk served as a cementing agent in the mortar used in Espada Aqueduct, the only such structure in the United States. Relative prosperity followed for a generation as this alluvial valley produced crops of maize, beans, melons, calabashes, sweet potatoes, and cotton, but deterioration had set in at Espada before the secularization of the mission in 1794, when only fifteen sick or aged Indians remained in the mission. Even so, dam, ditch, and aqueduct survived nearly a century of Indian attacks, ravaging floods, and controversy, both secular and clerical. The ditch had fallen into disuse for some fifteen years when, in 1895, the newly formed Espada Ditch Company repaired the dam, and enlarged the ditch while changing its course. When disaster again threatened to overtake this singular Spanish-American colonial irrigation project, in 1941 the San Antonio Conservation Society purchased this property to insure its preservation. Further assurance came in 1965, when the United States Department of Interior designated Espada Aqueduct as a Registered National Historic Landmark.