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a change in Mexico's cropping pattern. Similarly, as in Alternative No. 1, this is an action that is a prerogative of the Republic of Mexico and therefore beyond the scope of this report. 3. Alternative Plan No. 3 - Regulation of Drainage Pumping. This is the plan (with modifications) recommended in this report. The principal difference between the panel's plan and the plan proposed in this report is that the panel's report contemplates no pumping in Wellton-Mohawk during the winter months. Investigations for this report indicate that if there is no drainage pumping during the winter the saline concentration at Morelos Dam will be significantly increased during the summer months and that ground-water levels could encroach on the root zone in the Wellton-Mohawk area. 4. Alternative Plan No. 4 - Gravity Drainage of Wellton-Mohawk District. In this alternative plan the panel proposed tile or gravity drains for the irrigated lands in the Wellton-Mohawk District. Included in the plan would be a deep open drain more or less along the channel of the Gila River. The panel points out the following disadvantages of such a system. a. Such works would be costly. b. The open drain would be subject to flood damage. c. The gravity drain would continue to discharge in the winter months thereby preventing salinity concentration control by selective modification of flow quantities. The Board of Directors of the Wellton-Mohawk District has indicated its strong feeling as to the adverse effect of tile drains on 104Epson Perfection 4870 Photo, 400 dpi, 8 bit, 8,951,808 byte