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<br />In recent years, the failure rate has remained significant while <br /> <br />consequential costs have escalated. <br /> <br />Since 1965, 30 failures or serious <br /> <br />incidents that could lead to failure ha'le occurred, mainly from mechanical <br /> <br />flaws or overtopping from flash flooding (see llppendix 1). The Lower Latham <br /> <br />Dam (Weld County) failure in 1973 and the Lawn r,ake Dam (including the Cascade <br /> <br />Dam) in Rocky Mountain National Park in 1982 resulted in Presidential Major <br /> <br />Disaster Declarations. <br /> <br />The Lawn Lake di~;aster cost tm'e'e lives and at least <br /> <br />30 million dollars in damages. *3 <br /> <br />Of seven recent P:residE~ntia.l di saster <br /> <br />declarations in Colorado, two were dam failure floods; in other words, almost <br /> <br />one-third of all flood-oriented declarations in recent years have been dam <br /> <br />related (see Appendix 2). <br /> <br />Status of Dams in Colorado To review thE~ current status of dams, to <br /> <br />include their numbers and condition, the following facts are pertinent: <br /> <br />About 27,000 dams exist in the state, many of these an, small and <br /> <br /> <br />pose minor hazards: the federal 90vernlnent owns 120 dams in Colorado, <br /> <br /> <br />the state owns 89, other governments own 302 and the rest are <br /> <br /> <br />privately owned. <br /> <br />Many of the 27,000 dams in the s1cate axe old and in varied structural <br /> <br />condition; some exist near active faults or in areas where mild <br /> <br />seismic events occur. <br /> <br />To date, a comparison of active Eau11: loca- <br /> <br />tions and dam sites has not bee" made with enough detail to clearly <br /> <br />define seismic risks. <br /> <br />Strong notion devices have not been used to <br /> <br />assess internal stresses. <br /> <br />Thes" are projects which the legislature <br /> <br />may eventually fund, however sone indication of ris}~ can be deter- <br /> <br /> <br />mined if dam locations are c')mpared with t.he seismic activity <br /> <br />map and the Mercalli Scale. <br /> <br />* The earliest recorded dam failure flood in the Estes Park region occurred <br />on May 25, 1951, when Lilly Lake dam f"iled sending flood waters down Fish <br /> <br />Creek and into Lake Estes. <br /> <br />-5- <br />