Montezuma Well-
Rimrock, Arizona.
Montezuma Well is a collapsed carbonate caldron 368 feet across and 55 feet deep, and lies at 3,618 feet elevation in the Verde Valley. Its waters come from the southern Colorado Plateau just to the north. The springs well up from the bottom of a collapsed limestone sink and discharge through a natural tunnel at a rate of about 1,100 gallons per minute into Wet Beaver Creek, a tributary of the Verde River. The Well’s water is relatively const…ant in temperature, varying from 64 degrees to 77 degrees F, with relatively little dissolved oxygen but a high concentration of dissolved carbon dioxide and relatively high concentration of arsenic. The Well has existed at least through the Holocene Epoch (12,000 years) and likely much longer. The Well’s pool and outflow tunnel support at least five unique species: an endemic diatom, a springsnail, a water scorpion, an amphipod, and a new genus and species of leech. Over 1.5 million gallons of water flows into the Well every day, a rate that has not fluctuated measurably despite recent droughts throughout the state of Arizona. This water enters a “swallet” near the end of the trail into the Well and flows through over 150 feet of limestone before re-emerging from the outlet into an irrigation ditch on the other side. Sections of this ditch date back over 1,000 years.
Archaeological evidence suggests that humans have lived in the Verde Valley for at least 10,000 years. Several ancient dwelling ruins still stand on the sides of the rim above the well.
