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Our goal in monitoring depth at various locations across different habitat types was to find if depth was limiting or unsuitable at the recommended flow levels. For instance, if a flow of 1,630 cfs was recommended on the basis of providing near maximum area of preferred habitat, would depth of key habitats also be sufficient at that flow? For moderate-to-high flow summers, the recommended 1,630 cfs provided more than adequate depth (maximum and average) at the pool and the eddy transects (Table 5). However, suitable depth was not provided by 1,630 cfs at transects in the two backwaters. At backwater No. 1, increasing the flow to 2,870 cfs would provide greater depth but depth at both transects would still fall far short of being suitable. This was also the case for backwater No. 2. However, at the midway transect there, maximum depth sufficiently deep at flows less than 1,630 cfs once the bed elevation dropped in 1991, and average depth was nearly optimum (3.3 vs 3.4 ft) at 1,630 cfs. For low-flow summers, the recommended 810 cfs resulted in more than adequate depths at the deepest point along four fast-run transects and two of three slow-run transects. For winter use, maximum depths along the pool and eddy transects were suitable at 1,630 cfs. Average depth along the eddy transect at 1,630 cfs was also more than adequate though not so at the pool transect. Neither average nor maximum depths were suitable at 1,630 cfs for transects at backwater No. l . At backwater No.2, however, maximum depth at the upper transect was nearly deep enough (2.48 vs 2.60 ft.) at a flow of 1,630 cfs, and at the midway transect, maximum and average depth was sufficient, but again, only after the scouring flows of 1991. From the limited depth data that we acquired, it appears that depth of preferred habitats would not be improved significantly by adjusting the recommended flows upward within ranges typical of summer or winter conditions. Though the average depth along the transects often did not meet the minimum criteria for suitability, the maximum depth did. Average depth would be best because a greater volume of water could be exploited by one or more fish. However, with at least the maximum depth being optimum, we can assume an adult squawfish is capable of occupying some portion of a given habitat. The eddy and pool that we monitored maintained suitable depth at the recommended flows as did most of the fast and slow runs. Depth of both backwaters was unsuitable in 1990 and flows needed to provide suitable depth would be much greater than flows typical of summer or winter. However, depth of backwater No.2 was made suitable by spring flushing flows in 1991. The spring flows required to do this at backwater No.l are evidently higher. Backwater No. I was formerly used by squawfish in summer of 1986 and winter of 1986-1987 presumably when the bed was lower and the water deeper following the high flows of 1983-1986. After our stage monitoring ended, the bed at Backwater No. I was again lowered by the spring flows of 1993 (discussed later under Spring Flows). The summer and winter flow recommendations, designed to provide the maximum area of preferred adult squawfish habitat, should also be adequate to provide these habitats with suitable depth. Examination of stage and depth at bed cross-sections indicated that the recommended summer flow of 1,630 cfs would provide such depths in most cases. Backwaters are the most sensitive to changes in stage and most prone to sedimentation during years of low flow. To maintain adequate depth of backwaters in the 15-mile reach, not only should the recommended 44