Eight years in the making
The dam was born out of desperation. From the late 1890s into the early 1900s the Salt River watershed delivered a brutal run of dry years, and with no storage upstream the canals carried only what the river gave — some summers, almost nothing. Scottsdale farm families sold out and left; the settlement its founder had spent a decade recruiting was visibly shrinking. When the National Reclamation Act of 1902 offered federal construction money for western irrigation works, Valley landowners seized it. In 1903 they organized the Salt River Valley Water Users’ Association and pledged their own drought-stricken acreage as collateral — Scottsdale settlers signing alongside everyone else, mortgaging farms to pay for a dam none of them would live to see paid off.
Construction began in 1906 in a canyon 80 miles upstream, and stone by stone the tallest masonry dam in the world rose between the walls. By dedication day the structure was the showpiece of the entire Reclamation era, which is why the former president who signed the 1902 act came in person, up the Apache Trail, to say that this was among the achievements he was proudest to be associated with.
What the water bought
Scottsdale, downstream, felt the day less as ceremony than as arithmetic. The reservoir filling behind the masonry meant next summer’s water was certain for the first time in the settlement’s 23 years. Alfalfa, grain, dates, and orchards spread across the flats; farmhouses gained second stories; by 1913 merchant-farmer Charles Miller was building one of the town’s finer homes. One sting remained: founder Winfield Scott had died the previous October, months short of seeing the guarantee arrive.
The longer ledger is even more lopsided. Guaranteed water made possible the WWI Pima cotton boom that tripled the town, the guest ranches that followed the crash, and eventually a resort city of a quarter-million — every era of it drawing on the storage this day delivered. Eleven months later Arizona became a state, completing the decade’s opening trifecta; the whole run is told in the 1910s chapter and the year page for 1911.