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light of the truly extended steep slope barriers located some 10 to 12 miles west of the Cherry Cheek basin. Breaks in the barrier would permit orographic precipitation to be formed on the western ridgeline within the Cherry Creek basin. 1 do not believe the 9 percent addition reduction is totally justified. Additional Comments: I. In section 7.1 of the A W A team report, one is referred to a table 7.1 (See text - actual table not labeled) which provides a listing and total adjusted rainfall depth of the 10 storms transposed and clipped to the Cherry Creek basin boundary. Also referenced is figure 7.1 labeled "Storm Rainfall Mass Curve, Incremental Curve, and Envelopment Curve for the Combination of the 14 Major Colorado Storms". First of all, I am not clear as to what are the additional 4 storms used to develop figure 7.1 that are not shown in table 7.1 (please clarify). Secondly, and more importantly, the "Incremental Curve and Envelopment Curve" do not represent a PMP depth - duration curve for the Cherry Creek drainage using the data from AW A's table 7.1. According to table 7.1, the Frijole storm ofJuly 3, 1981, has provided a "Total Adjusted Rainfall Depth" of 12.21 inches of which fell in 4 hours according to the Frijole Creek storm summary provided in section 5.2. In this case, the maximum 4-hour depth from the "Incremental Curve" of figure 7.1 only totals about 5.75 inches. This situation needs to be clarified or all the curves redrawn on figure 7.1. Actually, the 4-hour, 12.21 inch value agrees quite well with the 6-hour PMP value of15.45 inches from the NWS 1995 study. 2. In section 6 of the A W A team report titled "Storm Maximization and Transposition", I see that these two important components of the PMP development, according to the WMO manual on PMP estimation, have been addressed and incorporated in the study. However, a third and just as critical component to the estimation ofPMP has been only partially incorporated into the final report and this deals with "Envelopment" (WMO 1986, pages 32-37). From the examination of figure 7.1 (AWA PMP study), I believe I see that Depth-Duration (DO) envelopment has been incorporated but I do not see where Depth-Area (DA) envelopment has been mention anywhere in the study. One needs to evaluate both these components in combination in what is termed by WMO as a Depth- Area-Duration (D-A-O) analysis to achieve the level ofPMP development. The result of D-A-D analysis very often presents a significant impact to final PMP evaluation. 3. The latest version of the A W A team report (dated April 2003) that I received on May 9, 2003; section 7.2 has now been omitted. Previously I had several serious questions regarding information and calculations shown in this section. I assume that this section is now deleted from the report. If this is true, suggest the title of section 7 be changed to read "Results" only.