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I I I I I I I I I I I I I I I I I I I 30 existing flow path. These facilities could daylight at the Town of Ordway Ditch. In the Central Basin, to fully conveyillll&'l!" flow to the existing box culvert at City Park would require 30- through 72-inch storm sewers, extending from the existing box, up Otero Avenue to 11th Street. Additionally, the existing box culvert would need upgrading to a 7-foot by 7-foot structure. At the outlet, of the new box, a grassl ined open channel with a top width of 50-feet woul d be requi red. The obvi ous expense of thi s system makes the implementation of such a plan questionable. The West Flow Path is not effected substanti ally by developed fl ows, because the volume of storm flow originating from the Northwest Basin is substantially greater than any developed flow from the Ordway West Property, and the property immedi ately north of Ordway West. The only hi storic flow to deal wi th woul d be that flow whi ch collects north of 11th Street, and moves south along County Road 17. Si nce the right-of-way is not a problem, an open channel could be used in place of a pipe system, and would have to extend from the intersection of County Road 17 and 11th Street, south along Road 17 to 1st Street, and then west to the historic outfall point for the Northwest Basin. Figure 7 presents a conceptual layout of the improvements to convey deve- loped condition flows along their historic flow paths. Diversion This alternative focuses on alleviating the existing and future flooding probl em by di verti ng stonn flows away from areas whi ch are known to be flood prone. This type of concept is a COlll11on alternative in areas where existing flow paths have been blocked by development. The flooding which results is usually shallow and of low velocity. In the case of Ordway, the existing drainage facilities are inadequate to convey the developed storm flow, and therefore, diverting the flow before it reaches these facil ities may be cost effective. The major problem with the diversion concept is that the rerouted storm flows must be controlled to a sufficient level whereby a new flooding problem is not created. Diversion of flows from historic paths is not practical in the Northeast Basin, or areas tributary to the Town of Ordway Ditch. The lack of adequate grades is the primary reason why diversion would be difficult to achieve. l -~