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The presence of the railroad embankment presented both benefits and threats. The obvious benefit was the immediate attenuation of the peak from the breach of the Havana Street spillway. The threat was that it was not designed to accommodate prolonged storage of water. Had the railroad embankment failed while holding this additional water, the damage downstream would most likely have been worse. The fast actions of the Refuge staff to alert the downstream communities so that appropriate evacuations could be made were an appropriate precaution. Their efforts to continue to lower the water level impounded by the railroad embankment with the use of auxiliary pumps was also appropriate. Figure 14 below is a false color aerial photograph taken on September 17, 2013 and shows the water impounded by the railroad embankment had drained within three days. Figure 14 - False Color Aerial Photograph - 17 SEP 2013. Source: DigitalGlobe The only observed damage that could be directly attributable to the Havana Street spillway breach appears to be erosion of the Havana Street roadway embankment as shown in Figure 7 below. The road was still passable despite the damage albeit at a diminished level of service. There may have been additional damage downstream, but given the nature of the floodplain and lack of infrastructure downstream of the dam to CO Highway 2, any additional damage is expected to consist of minor erosion of a nuisance nature. There were no known reports of CO Highway 2 overtopping so it appears that the storage created by the railroad embankment was able to safely retain the reservoir volume released by the Havana Street Dam failure and greatly reduce the peak discharge observed downstream releasing the floodwaters in a more controlled fashion which the infrastructure downstream could safely accommodate.