He was also instrumental in the drive to get the San Carlos Irrigation Project passed through the U. S. Congress, eventually leading to the construction of the Coolidge Dam.

[13] He was also appointed U. S. Land Commissioner for Pinal County in 1912, after Arizona was granted statehood, by Richard P. Sloan.

He had been re-appointed for an eighth term by Dave W. Ling, but he declined the offer, instead tending his resignation, feeling that "30 years was long enough for anyone to hold an appointive office".

In 1911, he traveled to Seattle, Washington, to personally escort the Secretary of the Interior, Walter L. Fisher, to Arizona, and go into detail about the necessity of the irrigation project.

[18] He was unopposed in the Republican primary, and won the general election in December 1911, becoming Arizona's first state senator from Pinal County.

In response, he authored S. B 191, which reorganized state irrigation districts, and establishing the reclamation service.

[22] When this bill failed to pass the legislature, Brown began working on preparing a referendum on the issue.

[27] He lost by two votes in the November election,[28] and demanded a recount, which came to the same result, but there were 50 contested ballots, 33 of which had been cast for Denton.

Arizona was strongly under Democrat control at that time, and Brown got the Republican nomination for state senator.

[33] Also in 1912, Brown began his efforts to create a diversion dam on the Gila River, ten miles north of Florence, which would enable the irrigation of 75,000 acres of farmland.

The group was formed to manage rental properties, such as hotels, apartments, and bungalow courts.

[39] The First National Bank of Casa Grande opened in 1920, with Brown on their board of directors, as well as being vice-president.