During this step, all the information on opportunities and constraints, and decisions that have gone before are brought together. Also called plan formulation, this is the process of identifying alternatives to achieve objectives while avoiding constraints. This is the point to brainstorm, think creatively, let no idea be ruled out immediately. Chapter 8 of the Planning Manual covers this topic. See pages 154-179 of the manual.
Possible physical actions, for example, to affect the flow and timing of a stream, are typical alternatives. Please see Bioengineering for Streams and Streambanks
for an annotation of documents that should be useful in developing alternatives. Another source of ideas is the EMRRP Tech Note page, http://el.erdc.usace.army.mil/emrrp/tnotes.html, which lists a variety of topics. Alternatives for both biological and engineering perspectives are represented. An additional source of ideas is the Wetlands Engineering Handbook found at http://el.erdc.usace.army.mil/wetlands/pdfs/wrpre21/wrpre21.pdf. (See chapters 3-6).