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I I I I I I I I I I I I I I I I I I I 22 Three drai nageways convey the flows from Town to Lake Meredi tho These are natural, grassl ined channels which may have once served as irrigation canals. The central basin, drained by the existing four-by-four box culvert, outfalls to poorly defined swales, of inadequate hydraulic capacity. This drainageway is aligned and passes near the Town's airport. This flow path will need reconstruction to ensure a safe conveyance of drainage to Lake f4eredi tho Floodplain Description As mentioned above, the Town of Ordway can be divided into three general flow paths, those being the eastern, central, and western flow paths. The flooded areas for the 100-year event have been shown on Figure 6. This information was developed using the hydrologic data, in combination with a hydraulic analysis of the existing street and storm sewer system. The analy- sis was supplemented with the Federal Emergency Management Agency (FEMA) Zone A Maps for the Town of Ordway. A description of the flooding information follows. Eastern Flow Path: The flooding which occurs within this area is largely the result of inadequate culvert capacity at the railroad crossing over the Town of Ordway Ditch. This constriction forces flow to backup to the level of the railroad grade, and would cause shallow flooding, west along Railroad Avenue. Several si ngl e-family residences and two busi nesses coul d be effected in a 100-year event. The Town of Ordway Di tch has adequate capacity to contain the 100-year flood event, if the rail road crossing restriction was removed. Most of the area currently flooded along the Eastern Flow Path would be removed from the fl oodpl a in, if a 100-year cross i ng was constructed at thi s 1 ocati on. The existing structure has less than a 10-year capacity. Central Flow Path: The areas inundated within the central portions of Ordway result from the lack of adequate surface and sub-surface drainage faci- lities. The railroad grade effectively blocks the flow along Railroad Avenue. The fl oodi ng is typi fi ed by one- to three-foot f1 oodi ng depths, and effects mostly single-family residences.