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r (., 3tH . . ./IPage 2 ..I river flow consisting of controlled releases and tributary inflow, or a flow of forty thousand cubic feet per second (cfs), whichever is greater, from below Davis Dam to the Southerly International Boundary between the United States of America and the Republic of Mexico. The standard level of protection that has been adopted in the administration of the National Flood Insurance Act is the one-in-one hundred year frequency flood. The Corps of Engineers has determined that 40,000 cubic feet per second (cfs) is the maximum release rate that historically would have inflicted a minimum level of downstream damages and has incorporated this flow level in its Hoover Dam flood control regulations continually since 1935. Consequently, the boundaries of the Colorado River Floodway should be capable of accommodating a one- in-one hundred year river flow or a 40,000 cfs flow, whichever is greater, from Davis Dam to the Southerly International Boundary between the United States and Mexico. It is the Comnittee's judgment that the Secretary's analysis of the one-in-one hundred-year river flow should represent a realistic one-in-one hundred-year probability of such flow occurring in any reach of the river at a given time, and should not arbitrarily assume that flood inflows from all tributaries occur simultaneously. It is the nature of weather events along the Lower Colorado River, a desert region, that most rain storms are intense, localized thunder showers that would produce floods from only a few tributaries at a time, and the Secretary's study should reflect this. Section 6. Limitations on Federal Expenditures Affecting the Floodway. This section states that, except as provided in Section 7, no new expenditures or new financial assistance rray be made available under authority of any Federal law for any purpose within the Floodway. Section 7. Exceptions. There are several functions and uses of the floodway that serve the public interest, and are generally canpatible with floodway operation. This section recognizes those functions and uses by providing limited exceptions, generally subject to Secretarial discretion, to the prohibition on federal expenditures. These exception'are enumerated as public and tribal roads, military activities, fish and wildlife enhancement projects, navigation aids, emergency action assistanCe, public health assistanCe, public and Tribal recreational developments, and compatible agricultural uses that do not involve permanent crops and include only a minirral amount of permanent facilities in the floodway. In general, the term "permanent crops" is to mean those crops which have a normal life of five years or more or which would be an obstruction to river' flood flows. In this regard, crops such as alfalfa, grains such as wheat, barley, oats, etc., asparagus, cotton, lettuce, cauliflower, melons, tomatoes, carrots, etc., should not be considered "permanent crops" for the