FLOOD01807 - Laserfiche WebLink

Home Browse Search

The equation for subregion ARK-I is: Q = 1572.8(A}547 Where: A = Drainage Area, square miles (25<A<1125) Q = 100 year peak flow, cfs ARK-2: SOUTHERN FOOTIDLLS SUBREGION This subregion includes streams within the southern foothills area. The streams in this subregion may have part of their drainage basins above an elevation of 7500' MSL, but this subregion only includes stream reaches that are downstream of (east of) the 7500' elevation limit. The subregion is bounded as follows: . On the south by the Colorado-New Mexico state line; . And on the east by the basin divide between the following watersheds: I. streams flowing into the Purgatoire River upstream of and including Trinchera Creek 2. streams flowing into the Purgatoire River downstream of its confluence with Trinchera Creek; · And on the east by the basin divide between the following watersheds: I, streams flowing into the Apishapa River upstream of and including Salado Creek 2. streams flowing into the Apishapa River downstream of its confluence with Salado Creek; . And on the east by the Huerfano River-Apishapa River basin divide; . On the northeast by the basin divide between the following watersheds; I. streams flowing into the Huerfano River upstream of and including the Cucharas River 2, streams flowing into the Huerfano River downstream of its confluence with the Cucharas River; . On the north by the Huerfano River-Greenhorn Creek basin divide; and . On the west by an elevation line of generally 7500'; The regression equation for this subregion is only valid for streams that have drainage areas between 12 mi2 and 280 mi2. A detailed study or other hydrologic analysis must be performed for projects involving streams with drainage areas Ihat fall outside of the applicable range. The equation for subregion ARK-2 is: Q = 3959.20(A)..... 10