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CARRIAGE HILLS NO. 2 DAM, Dam Failure Forensic Investigation Report Page 9 February 27, 2015 Nov. 14‐15, 2013: Two DSEs returned to survey the upstream and downstream stream channels and associated high water lines, to survey flood damage, and to meet with more eyewitnesses. 5. EYEWITNESS ACCOUNTS DSB staff attempted to interview neighboring residents after the Carriage Hills No. 2 Dam failure. This effort was hindered because many people in the surrounding neighborhood were either evacuated or had left town after the flood. Table 2 summarizes eyewitness accounts obtained by the DSB. Table 2: Eyewitness Accounts obtained by the DSB Name/address/phone number Date of interview Eyewitness Account Henry Rische / 1160 Lakeshore Dr. / 970‐ 586‐5591 9/26/2013 Mr. Rische reported water was flowing over the top of both Carriage Hills dams by daybreak on Thursday, 9/12/13. He reported a 2nd hand account that his neighbor heard a roaring sound early in the morning on Friday 9/13/13. Photos 15‐18 were taken by Mr. Rische’s daughter who had left town by the time of the interview. The photos are believed to have been taken on Thursday morning, 9/12/13. Anonymous woman residing at 1100 Scott Ave. 9/26/2013 Reported the lower Carriage Hills dam apparently broke overnight of 9/12‐13. The dam was gone on the morning of Friday, 9/13/13, when she woke up. Bob Harvey/ Pinewood Drive (upstream of Hwy 7) / 970‐576‐5576 11/14/2013 Mr. Harvey reported there were significant flood inflows to Carriage Hills No. 1 from a side tributary (unnamed) east of Larkspur Ave, east of Hwy 7 and entering over Carriage Drive. Also there was ~6‐in deep flow overtopping the paved bike path located ~300‐ft downstream of Hwy 7 (survey Cross‐Section 1) on the north tributary. He corroborated that the maximum high water level on the CO HWY 7 5’x7’ box culvert was probably at 3/4 height of the culvert. He said the culvert was not submerged and the road did not overtop. He reported significant flows coming off Prospect Mountain on the north side of north trib through the subdivision where he lives (Pinewood Drive). Charles Bonza / 1551 Fish Creek Road (corner of Country Club Road) 11/15/2013 Mr. Bonza reports at 9/12/13, 2200 hrs Fish Creek water level was at the bottom of his snowplow, immediately west of his driveway, when he looked outside. At 9/12/13, 2220 hrs Fish Creek surged and the water level rose approximately to the top of his snowplow (measured 2.1‐ft vertical). He believes this surge was caused by the Carriage Hills No. 2 dam failure. The floodwave reportedly receded in approximately 30 minutes (2250 hrs). Fish Creek level was reportedly steady before and after the surge. [DSEs surveyed the Fish Creek channel at the reported location of the snowplow during the flood]. Bonza videos / 1551 Fish Creek Road 9/12‐ 13/2013 Mr. Bonza provided us with 11 videos of Fish Creek flooding from Thursday 9/12/13 and the morning of Friday, 9/13/2013. We made the following notes from our review of the videos and based on Mr. Bonza’s comments in the videos: 9/12/2013, 03:00 hrs – Mr. Bonza reports he was still able to walk across Fish Creek to help his neighbor move things out of the flood (00365.MTS) 9/12/2013, 14:46 hrs [corresponds to a lull in rain according to AWA rain data, which is supported by the video] – Fish Creek flow had risen such that Mr. Bonza presumably could not walk across. Country Club Road was still intact but was shown overtopping by Fish Creek flood flows. Mr. Bonza notes that water had earlier pooled in his driveway and around the bottom of his snowplow (00365.mts)