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Comments of the Platte River Project on the Platte River Recovery Implementation Program DEIS The committee also recognizes, however, that there has been no substantial testing of the predictions of DOI's modeling work, and we urge that calibration of the models be improved and that monitoring of the effects of recommended flows and vegetation management be built into a continuing program of adaptive management ...." (p. 124) Notwithstanding these limitations, the DEIS establishes "performance criteria" for fluvial processes which are analyzed using the Sed Veg Model. The DEIS contains no summary of the accuracy and precision of Sed Veg in terms of its model processes or the raw data that is used for model runs. We question whether the lack of precision of the flow and sediment data, and vegetation germination and mortality data, used in the model is greater than the predicted trends. In addition, there is no quantitative discussion of the required river stage change; the number of days needed to create sand bars; how that information is accounted for in the model; or whether it historically occurred. The DEIS analysis appears simplistic with a one -to -one relationship between river stage and sand bar formation. No data is provided in the DEIS showing that the prescribed flow relationships and the magnitude and duration of flow recommendations will result in the scouring of vegetation. In fact, it is equally likely that the hypothesized processes for vegetation removal will have the opposite effect by distributing seedlings with a short term pulse, and ensuring their survival and growth (and narrowing of the channel) through late summer irrigation via release of so- called forage fish flows. We endorse the comments submitted by Gary Lewis and Carter Johnson critiquing the use of Sed Veg as an impacts assessment/management tool in the Draft EIS. The Sed Veg model should not be used to describe impacts, set performance standards or impact thresholds, or to make comparisons among alternatives. Given the uncertainties in the knowledge, a more qualitative assessment is needed with the understanding that the final Program would be structured to monitor actual effects and make adjustments through Program Adaptive Management to offset negative impacts as appropriate using proven habitat management methods. 6. The DEIS should evaluate the effects of the Proposed Program and its Alternatives commensurate with the duration of the federal action under review. The subject of the DEIS is the proposed 1St Increment of the Platte Program [DEIS, p. 1- 17]. The duration of that increment, and of the federal decision associated with its approval and implementation, is limited to 13 years. The Action Alternatives are scoped to embrace this incremental approach as a "common element," with only the 0 Increment under consideration at this time. [DEIS, p. 3 -181. At the end of 13 years, progress toward species protection, as well as the Program's ultimate objectives and goals, will be reassessed. [DEIS, p. 3 -24]. Subsequent in