Valley, to protect existing properties and open up new lands to agricultural production.
By the mid-1930s the progressive vision for water development had become national policy. Initial federal efforts to engage in river basin water management began with the Lower Mississippi Valley Commission during the presidency of Franklin Roosevelt. The 1934 National Resources Planning Board (NRPB), which undertook the task of defining how the natural resources of the nation could direct that era's weak economy to economic health, argued that water control structures were a part of the nation's economic relief and recovery effort; it stated (NRPB, 1934, p. 255):
[I]n the interest of the national welfare there must be national control of all running waters of the United States, from the desert trickle that might make an acre or two productive to the rushing flood waters of the Mississippi.
The NRPB's comprehensive watershed management program also included permanently converting steeply sloped lands that were in agricultural use to forest cover. The purpose served by reforested land was limited: these restored lands would reduce the intensity of runoff in order to reduce flooding. Deep percolation would store rainfall in ground water that would later be available for economic uses.
In 1950, President Truman's Water Policy Commission stated that integrated river basin planning could lead to the development of the nation's economy:
. . . the American people are awakening to the new concept that the river basins are economic units; that many problems center around the use and control of the water resources....
In summarizing the thinking of this era, Gilbert White articulated three elements to what Wengert (1981) later called the "pure doctrine" of river basin development: the multiple-purpose water storage project, an integrated system of projects within river basins, and the goal of water resources management being regional economic development. Plans for water development projects were expected to be defined through rational analysis by water management scientists, who would foresee the opportunities for water development and formulate the optimal sequence of projects to be put in place over time. This faith in scientific planning could be traced to the progressive era. For example, President Theodore Roosevelt, in a 1908 letter transmitting the report of the Inland Waterways Commission to the Congress (Morell, 1956), stated,