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I I I I I I I I I I I I I I I I I I I tJ00363 Colorado River water and future release ofICUA on listed species and their designated habitat. Effects to each species were determined for the most likely and low probability case scenarios. Habitat requirements for breeding, nesting, and foraging of some species are not dependent on the LCR. Fluctuations in water surface elevations associated with most likely and low probability storage and retrieval scenarios on reservoirs and riverine reaches on the LCR are very small and are not likely to adversely affect bonytail chub, razorback sucker, Yuma clapper rail, or southwestern willow flycatcher. Based upon the available information regarding the critical habitats for the razorback sucker and bonytail chub, storage and release ofICUA under this final rule will not adversely modifY critical habitat for these fish species. Other listed and sensitive species will not be affected by implementation of the rule. Reclamation did not consult with FWS on species in Mexico because the United States has no authority or discretion regarding Mexico's use of its treaty water or flood control releases. Reclamation has notified the National Marine Fisheries Service that a section 7 consultation for Mexican species under its administration is not required. Water Available for Instream Flows and Habitat Enhancement Comment: Concern was expressed that Colorado River stream flows downstream from Lake Mead would first increase when water is put into storage in Arizona and then decrease in the future as more water is diverted from Lake Mead when Nevada recovers stored water. Response: No significant changes are expected in stream flows downstream from Lake Mead as a result of implementation of a Storage and Interstate Release Agreement between Arizona and Nevada under the rule. The Biological Assessment for this final rule evaluated the effects of storage of 100 and 200 kaf7year of Colorado River water in Arizona and subsequent diversion in a later year of up to 100 kafby Nevada from Lake Mead. Very small changes in water surface elevations would occur in the riverine and reservoir areas below Lake Mead. The largest increase or decrease in average monthly water surface elevation when storing or using water was 0.12 feet. These changes fall within the range of increases and decreases in water surface elevations below Lake Mead and Hoover Dam under current river operations. Concerns over Deliveries to Mexico Comment: The DPEA states that a minor reduction will occur in the quantity of surplus water available for delivery to Mexico over the long term without explaining what a minor reduction is or what studies have been done to quantifY this. Response: Please refer to the previous discussion of adequacy of the environmental assessment under the Environmental Concerns section of the Public Comments on Proposed Rule and Responses on General Issues. 31