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" [\,.r'18 l)ul.U.i. 974 ECOLOGY lAW QUARTERLY [Vol. 28:903 significantly affect the critical Cienega de Santa Clara habitat by diverting and treating saline groundwater that currently flows to the Cienega. Indeed, a recent interruption in flows of Wellton- Mohawk drain water due to the 1993 floods on the Gila River led to the loss of between 60-70% of the Cienega's wetland habitat. 417 The biggest salinity problems historically have occurred below Imperial Dam.418 These problems are likely to be more acute because the EIS used 1997 Colorado River flows and salinity figures - a year of exceptionally high flows and correspondingly low salinity values (due to EI Niiio weather patterns) - to estimate salinity effects in the Lower Basin.419 As a result, the EIS almost certainly understated the salinity impact. A Delta restoration program could provide an innovative, cost-effective method of controlling or reducing Lower Colorado salinity. There are two equally effective methods for achieving salinity reduction: 1) reducing the salt load in the river through desalination or the elimination of sources of salt; and 2) increasing the flow of water in the river to dilute the existing salt load.420 Of the two, increasing the flow of water is by far the cheaper method of salinity control. 421 Transferring water to the Delta for instream flow would not only benefit the Delta, but the additional flow would also decrease the overall salinity of water along the Lower Colorado and as it enters Mexico, creating benefits that would significantly offset the cost of purchasing water for instream flows. The minimum flow necessary for initial restoration efforts, perhaps 32,000 af annually and a 260,000 af flood flow every four years,422 would produce a corresponding 2% increase in flows annually, and a 17% increase every four years.423 Because these flows would pass through Morelos Dam, they would also create supplemental salinity benefits by providing an additional outlet for salt, flushing out the reservoir. Even if increased flows reduced salinity by only a few percent at ~ I 417. Cohen et al., supra note 16, at 44-45. 418. See Law & Hornsby, supra note 171, at 88. 419. See FlNALEIS, supra note 71. at 3.5-8. 420. See Law & Hornsby, supra note 171, at 96. 421. SeeWAHL, supra note 116, at 262-63. 422. See Pitt, supra note 2, at 831. As noted in the Introduction, researchers have estimated the water required for initial restoration efforts in the Delta at 32,000 af annually. and a 260,000 00 flood flow every four years. In practice, however, the flow amounts might have to be larger in order to compensate for channel losses between Morelos Dam and targeted restoration areas further south. In that case, we expect the salinity benefits to be correspondingly larger. 423. 32,000 00 and 260,000 af are equivalent to approximately 2% and 17%, respectively, of Mexico's total allocation of 1.5 moo.