The six steps in the planning process used by the Corps of Engineers are:
A
Planning Primer published by the Institute for Water Resources (IWR) is a short
but excellent introduction (IWR 1997). The .pdf file is reproduced here 
and can be found at http://www.wrsc.usace.army.mil/iwr/Planning/97r15exp.pdf.
A more comprehensive document is the Planning Manual, also published by IWR. We have reproduced selected pages of the Manual, and also link to the full document on the Web site: http://www.wrsc.usace.army.mil/iwr/pdf/96r21.pdf(IWR 1996). When page numbers are provided, they refer to pages in the pdf file, not the printed version.
The planning steps are also summarized in the new Planning Guidance Notebook, ER 1105-2-100, which has been updated as of 22 April 2000: http://www.usace.army.mil/usace-docs/eng-regs/er1105-2-100/. To go directly to other relevant planning tools, visit the IWR pages at http://www.wrsc.usace.army.mil/iwr/pvrc/pages/library.htm.