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relationship for the individual precipitation stations in southwest Colorado. 'Jl1e annual I-day and 2-day precipitation amounts for the period of rccord were used to develop station statistics for seven precipilation stations in the region. The 1 % amounts were computed as well as relationship of 2~day: I-day ratio of 1% prccipitation amounts for each station. The precipitation stations, 1% amounts for 1- and 24day durations, and station ratios for 2-day: I-day arc listed on Table 12. An adopted regional ratio of 1.32 for 2-day to 14day relationship was used to obtain the 1% 2-day point rainfall ovcr the upper Dolores watershed. The adopted regional ratio is the average of the ratios computed for the scven stations shown below in Table 12. Table 12 Regional Analysis for I-day vs. 2-day 1 % Storm Precipitation Depths for Stations in or near Upper Dolores Rinr Basin Station Elevation 2-0ay I-day Ratio :"Jamc (feel) (inch) (inch) % Tct]uride 8672 4.4\ 3.09 ]42.7 Silvcrton 9278 4.04 3.]9 126.6 Durango 6600 4.15 3.12 133.0 Cortez 6153 2.80 1.85 15].4 Dolores 6940 2.86 2.13 134.3 Rico 8800 3.71 2.94 126.2 ~lancos 6990 2.49 2.27 109.7 Adooted Reeional Ralio 1.32 7.3 Stann Centerings. Two 1% general rainstoml centerings were de....e1oped for the upper Dolores Rivcr basin, one centered over the West Dolores River ("West Fork"), Ihe other o....cr the upper mainslem Dolores Rivcr ("Easl Fork"). The West Fork ccntering used a specific 1% stoml centered over the Wcst Dolores River near Stoner (WCSI Fork Dolores). with concurrent ccnterings (in descending order) on the upper mainstem Dolores River below Rico (Dolores Headwaters). Dolores Upper Mid. Bcar Creek, Dolores Mid, Dolores Lower. and Lost Canyon Creck. The East Fork ccntering used a specific 1% stann ccntcrcd over the upper mainstcm Dolores River below Rico (Dolores lIead\vaters), wilh concurrent centcrings (in descending 25