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. Henningson, Durham, Richardson 16) Commerce City 21) Englewood Sellards and Grigg, Inc. 19) Coal Creek 20) Fitzsimons 27) Highlands Ranch 28) Parker 29) Piney Creek 30) Kassler The consultants identified and coded each basin of 1000 acres or more, assigned runoff coefficients for hydro graph analysis, computed the A, L, LCA and S for the basin and prepared the narrative descrip- t.ion of the basin. They identified the basins through the physical features already included on the USGS quadrangle, and their own per- sonal knowledge of the area being studied. However, field investi- gations were necessary in some cases to determine basin physical boundaries. Definition of drainage basins extending over two or more quadrangles was accomplished by coordination between individual consultants. All finished mapping and basin descriptions were re- viewed for overall completeness and consistency by Leonard Rice Con- sulting Water Engineers, drainage consultant for Project REUSE, which coordinated the mapping effort. Special Considerations . Two conditions required special consideration. These are the numerous direct flow areas adjacent to the Sout.h Platte River and the Barr Lake drainage area in Adams County. The shape of the direct flow areas that drain into the South Platte River with no defined channel do not lend themselves to CUHP analysis. Therefore, only the physical basin boundaries and drainage area are defined because the values of the L, LCA and S parameters are meaning- less. There are similar instances on the tributaries and drainageways where areas are defined in a shape not compatible with CUHP analysis, In these cases, however, the various parameters are defined to allow the users to decide the value of the parameters and method of analysis for themselves. This is also desirable for standardization because the opinion of individual consultants can vary. The Barr Lake drainage area is physically defined on the quadrangle map, but because the area is primarily a rural area draining northward out of the UDFCD boundaries, it was not included in the requirements for definition of physical parameters or narrative description. In defining the drainage basins within the UDFCD, the consultants stop- ped at,or reasonably near, the Drainage District boundary at some logi- cal physical point. In some cases, this resulted in small areas within the UDFCD not being defined. In other cases, it resulted in areas beyond the boundary being included in the study. . It should be noted that in 1971, the Colorado State Legislature ex- cluded a portion of the Urban Drainage and Flood Control District from the District area as described in the original enabling Act. This area encompassed the St. Vrain river basin. Since the exclusion was not 7