FLOOD10463 - Laserfiche WebLink

Home Browse Search

In the late 1800s, coal mining led to the development of Erie and several other small communi ties along the banks of Coal Creek. Because the coal reserves have diminished and most of the mines have been shut down, Erie is now mostly commercial and residential, with some agricultural development in the surrounding area (Reference 2). The estimated population of Erie was 1,231 in 1980 (Reference 3). The average annual precipitation in Erie is 12.7 inches, and the normal mean temperature is 48.60F. In 1976, the temperature varied from a July average of 71.60F to a January average of 26.80F (Reference 4). Vegetation in the area consists primarily of native grass. The soils in the area are shallow, very gravelly and stony, and in the rock outcrop-Juget-Baller Association (Reference 2). The topography in the developed part of Erie is relatively flat and gradually slopes toward Coal Creek. Both residential and commercial development exists in the floodplain area. Coal Creek flows northerly along Erie's eastern corporate limits and empties into Boulder Creek. The Coal Creek West Line Overflow begins south of Erie, where floodwaters from Coal Creek overtop the UPRR, and flow northerly, independent of Coal Creek, through the fully developed area of Erie before returning to Coal Creek north of the town. 2.3 Principal Flood Problems The main sources of flooding on Coal Creek are heavy thunderstorms in spring and summer. Flooding can become especially severe when these thunderstorms follow either rapid snowmelt or prolonged rainy weather (Reference 2). Floods have occurred in 1876; in 1891; in June 1896: on June 3, 1921: on May 26, 1935; on September 2, 1938; on June 9, 1949; on May 9, 1957: and in May 1969. The estimated discharges for these events at Erie are shown below (Reference 2). Date of Flood Discharge at Erie (Cubic Feet per Second (cf s) ) Approximate Frequency 1876 June 3, 1921 September 2, 1938 13,200 7,800 3,500 100-Year 20-Year 5-Year The amount of damage from these floods is unknown. Flood discharges were estimated by the USACE using the slope-area method. The 1876 flood is the maximum flood of record at Erie. recent flood occurred in May 1969. The most 3