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 Page 2 Upper and Lower Emerald Valley Dam Failure Report January 23, 2015 The scope of the study included:  Interviews of the dam owner and downstream property owners,  Field inspection and survey of the dam breach and creek flooding,  Review of processed rain data from the Sept. 2013 event,  Analyses and discussions based on this information. 3.0 General Background UEV & LEV Dams (both non-roster dams) overtopped and failed during the September 2013 widespread catastrophic flooding in Northern Colorado and the Pikes Peak Region of El Paso County. The storm was an unusual, late season event whereby warm moisture and upslope winds allowed up to 16-17 inches of rain to fall at elevations as high as 10,000 ft. The rain event was long and high volume but relatively low-intensity. It caused extensive flooding throughout Northern Colorado and also the Pikes Peak Region. State climatologist, Nolan Doesken, confirmed that 11.85 inches of rain fell over 24 hours at a rain gauge at Fort Carson on 12 SEP 2013, just to the north and east of the Emerald Valley Basin. More than two-thirds of that fell in over just three hours. While northern Colorado had more total rain over a larger area in September, Mr. Doesken says no official record is kept for most rainfall in a week. The new record breaks the previous one-day, Colorado official rainfall total of 11.08 inches in Holly, CO in 1965. UEV & LEV Dams are owned by the Broadmoor, as part of their Emerald Valley Ranch Resort, which is comprised of the lakes formed by the two dams and numerous rehabilitated historic cabins. The Emerald Valley Ranch resort is operated by the Broadmoor on US Forest Service property, under the requirements of an USFS Special Use Permit. From a regulatory perspective, this office (including previous dam safety engineers) was unaware of the existence of these structures, primarily due to their minor size (surface area on normal day of about 1 acre for the larger LEV Dam). There is no information in our DAMS database for any water impounding structures in this area (to include Erosion Control dams and/or Livestock Water Tanks). The structures are considered non-roster dams and their presence was only made aware during reconnaissance by this office during the regional flooding event, as follows. During the days of 12 & 13 SEP 2013, this office was busy making phone calls to dam owners potentially affected by the regional flooding event. One such dam owner was the Broadmoor, who owns a High Hazard dam on the east slopes of Cheyenne Mountain, Fisher Canon DAMID 100121. During the call to check again on the status of Fisher Canon on 13 SEP 2014, a representative of the Broadmoor informed this office that the two dams on Emerald Valley Ranch had failed the previous day. A review of the location of Emerald Valley Ranch was made, the approximate size of the dams determined through aerial photos, and a call was made to the downstream owners of Keeton Reservoir. Keeton Dam is owned by the City of Fountain and is located about 4 miles downstream of Emerald Valley. The Emerald Valley dams lie in series on Little Fountain Creek, about 6.5 miles southeast of the summit of Pikes Peak. The dams are accessed from Old Stage Road south onto FR 371. Keeton Dam is located about about ½ miles west of Colorado State Highway 115. Figures 1, 2 and 3 show a vicinity map, location map, and 2011 aerial image around the dams.