Lake Mary, a man-made body of water, was created less than a year after a dam was built in a shallow valley south of Flagstaff. Remnants of a temporary sawmill and living quarters can be seen in this March 1905 photograph of the lake, which measured half a mile wide, 6 miles long and 28 feet deep.
The town of Flagstaff had been on the hunt for a water supply that would satisfy domestic and industrial needs nearly since the community was formed in the 1880s. The steam engines on the railroad needed water and so did the engines used in the sawmills.
The town needed to find something more reliable than the few springs around town, which dried to a mere trickle by early summer.
Initially water for domestic use had to be hauled and kept in barrels at each home or business. In 1901, the town built an elaborate piping system that brought water down from the inner basin of the San Francisco Peaks. Water rates were $2 for the first 1,000 gallons, 15 cents for each additional 100 gallons up to 2,000 gallons and
5 cents for each 100 gallons thereafter. There was enough water for homes and businesses, but not nearly enough for the sawmills.
The Riordan brothers, Michael and Timothy, owners of Arizona Lumber and Timber Company, had developed an electric light plant, which served their business and also the community, and was operating by 1903. The next obstacle to expanding their logging operation was water, and they tackled it with their usual energy.
In 1904, the Riordans explored the Little Valley, south of Flagstaff. Homesteaded by early settler John Clark, a sheep rancher, Little Valley, also known as Clark’s Valley, was the site of temporary sawmills, which processed logs brought in on a narrow gauge railroad from the south. Its flat basin formed a grassy meadow fed by many tributaries during the spring melt.
The Riordans proposed to build a rock dam across a narrow cut of malapais rock at the north end of the valley to catch the runoff, which normally flowed into Walnut Canyon. The lake would serve both industrial and municipal uses.
When the dam was completed in 1904, it stood 38 feet high, was 1,014 feet long and 751 feet deep. The lake that formed behind it held slightly more than 4 million gallons of water. The Riordans named it Lake Mary after Timothy Riordan’s eldest daughter Mary.
The lake immediately became a popular place for boating and fishing. The local newspaper reported on its virtues for duck hunting, ice skating and fishing. Three small boats were bought for pleasure use with orders placed for “a couple of auto boats” as well. That spring, when the lake was filled to capacity, sailboat races were held. And the next summer, the lake was stocked with 15,000 black bass.
But from the beginning, the lake couldn’t hold water. The basin sat on top of porous limestone formations, which created numerous sinkholes in the basin, draining off the water slowly during hot summers and dry winters.
In 1941, the city of Flagstaff finally addressed the problem and built a second dam south of Lake Mary, creating Upper Lake Mary. Built away from the malapais and limestone formations, the lake held water and with the help of several wells dug in the area before the second lake filled, provided an assured water supply for the city.
Today, the upper lake provides year round recreational opportunities to water skiers, boaters and, in the winter, ice fishermen.
The lower lake is seasonal — dry most of the time except in wet years when the shallow basin again fills with water. Both lakes are favorite hunting areas for humans and animals.
— Joan Brundige-Baker. Photo courtesy Cline Library, Northern Arizona University.