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him (although it may be a subsidized cost) and the savings in costs which can be realized if steps are taken to reduce the hazard. This is an incentive for greater implementation of nonstructural measures. This savings may be small because of the regulato'Y.practice of offering subsidized rates to existing structures and requiring new structures to build at or above the 100 year level and because premiums do not reflect" non insurable" damage. Also, a savings is not available for all adjustments. Raising a new or existing structure to the 100 year level, keeping a structure out of the flood plain, or removing structure and/or contents to a flood-free. site all may yield a premium savings. Other adjustments such as closures for openings, rearranging or protecting damageable property within a structure, or building a small wall or levee, do not at the present time, resu'lt in a premium savings. Degree of Protection Degree of protection has traditionally been used as an indicator of project performance to define the exceedance interval of the flood event at which flood damage begins. It is the minimum protection provided by a project and is associated with a particular river location. Structural measures, because they are designed to control flood waters, generally provide the same protection to all structures at that location. For example, a reservoir or levee by controlling a particular flood event controls it for all structures within the flood plain of that event. It is more difficult to provide this type protection with nonstructural measures because most measures are applied to individual structures and each structure varies as to type and location in the flood plain. Also, a nonstructural plan is likely to be a mix of measures and there are limits to the feasibility of each type measure. This is especially the case for existing structures. Uniformity of protection is less difficult for new structures. Flood plain regulation, elevating new structures, and flood plain acquisition all provide the opportunity for uniform protection of future development. In a practical sense when developing a plan using nonstructural measures it is likely that some measures will provide protection to one level and others to another, and it will be difficult to provide the same protection for all structures. It is likely each structure or group of structures will have its own degree of protection. For this reason the indicator, degree of protection, in its traditional sense as one value for all structures, is not as useful in nonstructural formulation. I n addition to the difficulties mentioned above, there is also the fact that different nonstructural measures by their nature provide different degrees of protection. If a structure is raised to the 100 year flood elevation the degree of protection would be 100 years. However, a structure removed from the flood plain or prohibited from locating in the flood plain has very large protection. The term "protection" itself is relative when applied to nonstructural measures. A small wall or levee is designed to keep flood waters fro~ coming into contact with both structure and contents. Temporary or permanent closures, however, while protecting the contents incur residual damage to the structure. Flood insurance has the unique feature that it doesn't protect (reduce damage) in the traditional sense, but indemnifies the policy holder against financial loss. A major factor when establishing degree of protection is the severity of damage should the protection be exceeded. Selecting the appropriate measure for the hazard situation, together with proper design can minimize this potential damage. For example, closures on doors or windows would not be appropriate if walls and floors could not withstand the hydrostatic forces. A structure raised on columns should be designed with the knowledge that it is likely to 8