Shortly after the Gadsden Purchase, Charles Trumbull Hayden moved out West and opened a general store near Tucson. While traveling to Prescott on business, Hayden was delayed for several days due to high water at the Salt River. Heavy storms frequently flooded the river, making the river dangerous and unpredictable to cross. Seeing a need to safely cross the river, Hayden purchased 160 acres of surrounding land in 1870, and opened a mill, a general store, a black smith, and a ferry.
A railroad was constructed in the late 1800's, but constant flooding destroyed the tracks, and then later destroyed the replacement tracks.
The ferry remained in service until the early 1900's, however the waters were still unpredictable.
In 1911, the Roosevelt Dam was completed, which allowed the river to be better managed. That same year, Governor Hunt commissioned the construction of the Ash Bridge, which was completed two years later, and allowed locals and travelers to cross the once unruly river.
With quickly advancing technology, the Ash Bridge found itself fallen behind the times. Heavier and wider automobiles made the narrow bridge inconvenient for users, and a flood in 1916 damaged the bridge so it was no longer safe to use.
In 1928, a group of Tempe businessmen submitted a request to the Arizona Highway Commission for a new bridge. Engineer Ralph Hoffman submitted plans for what is now known as the Mill Avenue Bridge. (Then called the Tempe bridge.) The bridge opened in the Summer of 1931, and the bridge was a huge success, being able to handle both two-way traffic, and the seasonal flooding of the river. Two years after the bridge opened, Governor Moeur held a two-day dedication ceremony. The bridge is still operational today, and is located in nearly the exact same spot as Hayden's original Ferry crossing.
With the construction of new dams for the Salt River, the crossing in Tempe dried up, and left an unsightly riverbed running through the town. Locals called the area the "scar of the valley."
In 1966, a group of architecture students at ASU were tasked with creating a plan that would safely restore water to the river bed, while still allowing development of the surrounding town.
The following year, the students submitted their plan, which was not just for Tempe, but for the entire county of Maricopa. They named their project Rio Salado. They wrote, "The Rio Salado has given Phoenix its life. Now Phoenix can return life to the river and benefit greatly from that act. For men of vision and leadership, this is a noble goal. One that is within reach."
It took twenty years for the Rio Salado plan to make it to the ballot. In 1987, voters were presented with supporting new lakes, parks, and development through a property tax increase. The bill failed 2-1, but it passed in Tempe. So Tempe decided to go ahead with their part of the plan, and construction began in 1994 on what is now known as Tempe Town Lake and Tempe Beach Park. In 1999, water was returned to the Salt River, and thousands of people came to see, celebrate, and enjoy the new Tempe Town Lake.