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Table 2. Explanation 1. Reservoir Instream Flow Requirement - The Instream Flow Requirement (IFR) is used to provide desired releases from a reservoir. These releases can vary from month- to-month and from year-to-year. An IFR is a demand that requires a flow (specified by a monthly table) to be maintained in the stream at the station. An IFR may have either a natural right or a project right, but not both. Water is water to an IFR, and either kind of water (natural or project) will work to satisfy it. Only a project IFR may demand the release of stored water and water flowing through an IFR is not withdrawn from the stream, and is available for use anywhere below the IFR station. 2. Maximum Content Capacity - This table gives the maximum allowable content in the reservoir each month. If omitted, HYDROSS uses the last (highest) value in the Reservoir Contents Table (see above). HYDROSS will try to release (either discharge or spill) any water above this level. However, the release may be blocked by a channel capacity constraint downstream, or by the outlet works capacity if the level is below the spillway elevation. 3. Minimum Content Capacity - This table gives the minimum allowable content in the reservoir each month. If omitted, HYDROSS uses the first (smalledt) value in the Reservoir Contents Table (see above). HYDROSS will not release water below this level for any reason; the only losses will be seepage (see below) and evaporation. 4. Target Content Capacity - This table gives the desired content in the reservoir each month. If omitted, HYDROSS uses the maximum content (see above). The target content is used for pool maintenance and for determining diversion demands for off-stream storage. 5. Evaporation - This is a monthly table of (linear) values which give the depth of evaporation per unit of surface area. Multiply by the surface area to get the water volume lost to evaporation in a month. If omitted, evaporation will be zero. 5