Coordinated comprehensive planning at the regional or river basin level, or for an urban or metropolitan area, can help to achieve solutions to flood problems that adequately reflect future changes in watershed conditions, and help to avoid short-sighted plans serving only localized situations. This planning is particularly important in areas where significant portions of a watershed are expected to be urbanized in the future. Changes in land use may result in major alterations of the runoff characteristics of the watershed. Hydrologic changes must be projected for the period of analysis. In this effort, responsible local planning organizations should provide information and assist the Corps in development of projected land uses and expected practices for collection and conveyance of runoff over the period of analysis. Conversely, the Corps may be able to provide non-Federal interests with valuable information about water related consequences of alternative land uses and drainage practices.