Hohokam Canal Builders of the Salt River Valley 7th grade · age 12

The Judgment Lab asks: What do we think about that? When we work on the Judgment Lab, our ultimate goal is to articulate our own principles and values in a thoughtful and respectful way.

As you know from the reading, the Hohokam settled in the Salt River Valley in what is now Arizona, surrounded by the Sonoran Desert. The desert received only a few inches of rain each year, so farming depended entirely on water from the Salt River. Between AD 900 and 1450, Hohokam laborers used stone picks and bone tools to dig more than eight hundred miles of main canals, plus hundreds of additional miles of smaller branches. One system alone could irrigate an estimated ten thousand acres of farmland.

All that water allowed Hohokam farmers to grow far more food than their own families needed. Those surplus crops fueled a trade network stretching from Mexico to Utah to the Pacific Coast to the Great Plains. The Hohokam raised multistory buildings and ball courts. But here is the key point for this Judgment Lab: a canal system that big could only work if people kept digging, cleaning, and maintaining it together. A family living at the far end of a canal branch still depended on the main trunk line upstream — the big channel that carried water from the river before it split into smaller branches serving different villages.

When the system eventually broke down, the results were devastating. By the 1300s, prolonged drought and crop failure likely drove the Hohokam from the settlements they had spent centuries building. They abandoned their canals, ball courts, and multistory buildings, and scattered into smaller communities across the region. The collapse reminds us how much every family and village along the canal depended on the whole system staying in working order.

The Judgment Lab asks under what conditions we owe labor, money, or other support to people outside our own family or village. Another way to say this is: when should someone be required to contribute to a shared system that benefits a larger group, not just themselves? The Hohokam canal is one example, but people face versions of this question all the time — for instance, when a town collects taxes to pay for roads, bridges, or schools that not every family uses equally.

Should that family at the far end of the canal have been required to send its workers upstream to fix a trunk line that also served other villages — even if the work was hard, dangerous, or took time away from their own fields?

Follow the steps below to complete this Judgment Lab. By the end of the lab, you will have decided whether a Hohokam family living at the far end of a canal should have been required to help repair the main trunk line upstream, even though those repairs helped villages other than their own. You will also articulate and test your principles about under what conditions we owe labor, money, or other support to people outside our own family or village.