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card, the ET card, and the table of discharges (QT card). To compute a natural water surface profile as the first profile of a multiple profile run, either INQ (Jl.2) must be zero (i.e., to ,indicate that cards ET and ~T are not read) or the field on the ET card called by INQ for the first profile must be blank (no encroachment used). The latter approach is used in this example. The Jl cards for subsequent profiles call field 3 (INQ=3) for an encroachment based on an 0.8 foot rise in water surface (d.4* in field 3 of ET card) and field 4 (INQ=4) for an encroachment based on a one foot rise in water surface (10.4 in field 4 of ET card). The starting water surface elevation to be used for the encroach- ment profiles would start at the same elevation as for the natural profile. starting elevation is fixed by a lake or other control, the encroachment profiles would start at the same elevation as for the natural profile. If the reach under study is part of a stream in which future downstream encroachments could cause a rise in water surface elevation, then the encroachment runs should be started at the higher elevation. For this example, the starting elevations are assumed to be equal to the starting elevation for the natural profile plus the one foot increase. The example output for the second profile shown on page 7 of Appendix II contains two statements that supplement the normal print- out. These statements are explained in Exhibit 9A. The first statement, preceded by the number 2800, gives the conveyance data computed by the program and the second statement, numbered 3470, gives the computed encroachment stations, the encroachment method used, and the ratio of *The encroachment method is given to the right of the decimal (.4 for Metned 4) and for Method 4, the change in water surface elevation is given in tenths of a foot to the left of the decimal. 10