Within three days, 8–11 inches (200–280 mm) of rain fell throughout the Great Miami River watershed on already saturated soil,[2] resulting in more than 90 percent runoff.

[4] Initial access was provided by the Dayton, Lebanon and Cincinnati Railroad and Terminal Company, the only line not affected by the flood.

[14] Governor Cox called on the state legislature to appropriate $250,000 ($7.71 million in 2023 dollars) for emergency aid and declared a 10-day bank holiday.

[15] When newly elected President Woodrow Wilson sent telegrams to the governors of Ohio and Indiana asking how the federal government might help, Cox replied with a request for tents, rations, supplies, and physicians.

[16] Governor Cox sent a telegram to the American Red Cross headquarters in Washington D.C. requesting their assistance in Dayton and surrounding communities.

[5] Patterson organized rescue teams to save the thousands of people stranded on roofs and the upper stories of buildings.

[5] NCR facilities served as the Dayton headquarters for the American Red Cross and Ohio National Guard relief and rescue efforts and provided food and shelter, a hospital and medical personnel, and a makeshift morgue.

Patterson also provided news reporters and photographers with food and lodging and access to equipment and communications to file their stories.

Led by Patterson's vision for a managed watershed district, on March 27, 1913, Governor Cox appointed people to the Dayton Citizens Relief Commission.

Morgan hired nearly 50 engineers to analyze the Miami Valley watershed and precipitation patterns and to determine the flood volume.

[4] The analysis had determined the river channel boundaries for the expected 1,000-year major floods, and all businesses located in that area were to be relocated.

[citation needed] With the support of Governor Cox, Dayton attorney John McMahon worked on drafting the Vonderheide Act, Ohio's conservancy law, in 1914.

Controversial elements of the Act gave local governments the right to raise funds for the civil engineering efforts through taxes and granted eminent domain to support the purchase or condemnation of the necessary lands for dams, basins, and flood plains.

[27] The constitutionality of the Act was challenged in Orr v. Allen, a lawsuit brought by a landowner affected by the exercise of eminent domain, and attempts were made to amend it through the Garver-Quinlisk bills.

As a result of establishing the conservancy area, the rail lines were moved several miles south out of the floodplain to run through Fairfield, Ohio.

To alleviate flooding conditions, local government leaders used dynamite to remove locks in the canal to allow the water to flow unimpeded.

Since they were no longer economically viable, Ohio's canals were simply abandoned except for limited sections that supplied water to industry.