Laserfiche WebLink
<br />HMS model. The HMS model is currently set up for 15-minute time ordinates; the number of <br /> <br />e <br /> <br />sub-reaches used for each routing reach is the whole number of 15-minute increments in the travel <br /> <br />time for that reach. The Muskingum X, Muskingum K and number of sub-reaches computed for <br /> <br />each routing reach in the HMS model for the 1970 event are listed on Table 9. <br /> <br /> Tablle 9 <br /> Muskingum Parameters <br /> (Most Upstream Point to McPhee Reservoir) <br />Reach Name Length Muskingum Muskingum Number of Slope <br />ID# (mi) K (hrs) X Sub-Reaches (ft/mi) <br /> . <br />R620 10.5 2.1 0.40 8 47.8 <br />R630 11.3 2.3 0.40 9 49.7 <br />R810 14.6 2.9 0.40 12 28.1 <br />R780 3.9 0.8 0.40 3 7.7 <br />R760 3.4 0.7 0.40 3 32.6 <br />R800 0.4 0.1 0.40 1 75.1 <br /> <br />e <br /> <br />6.8 Precipitation Used for 1970 Flood Reproduction. A regional isohyetal map <br /> <br />developed by the National Weather Service (Plate 9) was used to distribute precipitation for the <br /> <br />1970 flood simulation (Reference 4-j). Hourly precipitation records are available from the <br /> <br />Pleasant View, Mesa Verde National Park, Durango, Telluride, Silverton and Ouray gage <br /> <br />locations. The Silverton precipitation distribution pattern was selected as best representing the <br /> <br />timing and magnitude of peak runoff obst::rved at Rico and Dolores; and the user gage weighting <br /> <br />method was used for the 1970 HEC-HMS model. Each subbasin was apportioned precipitation <br /> <br />based on the isohyetal map and orographic considerations (Table 10). <br /> <br />- <br /> <br />2" <br />~. <br />