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DaM Failure: a growing risk as structures age. Marty Pope Senior Service Hydrologist NWS Jackson. Average risk of any dam breaking in a given year: 1 in 10,000 Average age in years of dams in US: 40 Third of our nation’s dams age: 50 years old
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DaM Failure:a growing risk as structures age Marty Pope Senior Service Hydrologist NWS Jackson
Average risk of any dam breaking in a given year: 1 in 10,000 • Average age in years of dams in US: 40 • Third of our nation’s dams age: 50 years old • In 10 years, more than 65% of dams in the U.S. will • have reached the half-century mark. • The Cost of Rehabilitating Our Nation’s Dams: • $16 billion to repair the most critical dams next 12 • years. • Number of dam break deaths in U.S. since 1887: 4,800 Dam Statistics Source: -Damsafety.org Website -International Rivers Website As of 2007 Local Govt Owned - 20% Federally Owned - 4% Privately Owned - 65% State Owned - 5 Unknown Owned - 4 Public Utility Owned - 2
In the past 20 years, there have been over 300 fatalities in the U. S. resulting from dam failures. South Fork Dam – Johnstown, Pennsylvania – failed in 1889, approximately 2200 killed. St. Francis Dam – California – failed in 1928, 450 killed. Baldwin Hills Dam – California – failed in 1963, 5 killed. Buffalo Creek Dam – West Virginia – failed in 1972, 125 killed. Teton Dam – Idaho – failed in 1976, 11 killed and ½ billion dollars in property damage. Kelly Barnes Dam – Georgia – failed in 1977, 39 killed. Lawn Lake Dam – Colorado – failed in 1982, 3 killed. Kaloko Dam – Hawaii – failed this year, 7 killed. Significant Dam Failures
State-Regulated High-Hazard-Potential Dams, 1998-2007 • 4,095 state-regulated dams are in need of remediation. • 1,819 of these deficient dams are classified as high-hazard-potential dams, and 1,126 are classified as significant-hazard-potential dams. The Potential for Catastrophic Dam Failures Is Increasing Nationwide
Good NEWS: The number of state dam inspections is increasing
GOOD NEWS: States are increasing the number of current emergency action plans (EAPs) on high-hazard potential dams
http://mesonet.agron.iastate.edu/cow/?syear=2012&smonth=8&sday=30&shour=5&eyear=2012&emonth=9&eday=4&ehour=12&wfo=LIX&wtype[]=FF&hail=1.00&lsrbuffer=15<ype[]=FF&wind=58http://mesonet.agron.iastate.edu/cow/?syear=2012&smonth=8&sday=30&shour=5&eyear=2012&emonth=9&eday=4&ehour=12&wfo=LIX&wtype[]=FF&hail=1.00&lsrbuffer=15<ype[]=FF&wind=58 Events of Isaac
At 8:10 am, MEMA reported that the Percy Quinn Dam was expected to fail via email • 8:26 am, LIX WFO issued Flash Flood Warning for Southwestern Pike County • Warning included Osyka area and all low lying areas of the Tangipahoa River in Mississippi. • LIX WFO coordinated with LMRFC to proceed with dam break analysis • RVFs were coordinated and updated to add dam crest to occurring flood risefor Osyka and Kentwood • At 11:07 am, CEM was composed and activated for Percy Quinn Dam • At 11:11 am, LIX WFO issued Flash Flood Warning to Pike County and Northern Tangipahoa Parish to include Kentwood. • At 2:00 pm, the LIX WFO issued a Flash Flood Statement indicating that the Warning would expire for Pike County and Tangipahoa Parish, but would be monitored and a warning reissued if conditions deteriorated. Percy Quinn Dam - Timeline of events – August 30th
As a result of the Percy Quin Dam incident during Isaac… the MS Silver Jackets Team (consisting of National Weather Service, US Army Corp of Engineers Vicksburg, United State Geological Survey, MS DEQ Dam Safety Division and MEMA ) along with several local Emergency Management officials have met together to discuss Dam Break incidents and the role of each agency. • Action Items of team: • Team is working for better communications between agencies during a Dam Safety Incident. • Team is working is working to relay a message about a dam safety incident in language all are familiar with including the public. • Team agreed the National Weather Service should be listed as an upper level contact on EAP contact list. • Note: These action items can also be used by Arkansas and Louisiana. What are we doing in Mississippi to prepare for this threat?
All Emergency Action Plan (EAPs) will include language that is consistent with the National Weather Service’s Advisory, Watch, Warning, and Emergency Criterion. • DEQ will rewrite EAP guidelines….this should take a couple of months after a review period. • All Emergency Action Plans will be place a repository that can be accessed by the National Weather Service and Emergency Management Officials. • DEQ will hire a contractor to scan all Emergency Action Plans that will be placed a Website. All should be scanned and on a website in 2 to 3 months. • The MS DEQ Dam Safety will provide NWS and EMA officials needed access to Emergency Action Plans (EAPs) via a website. • DEQ will provide Emergency Managers trainings on Dam Safety and evaluating Dams . • This will be in cooperation with the National Weather Service. • This training will not be available until all EAP guidelines are completed. • DEQ will provide a 1-800 phone number that will first ring to all of the Dam Inspector’s office telephones and if no one answers….then ring to their cell phones Mississippi DEQ Dam Safety Division Actions
WFO Operations During Event • Determine if dam incident report is from a reliable source. (dam owner, state dam safety official, emergency management personnel, or local law enforcement officials) • “If report cannot be verified, the WFO should use best judgment in selecting the appropriate course of action.” • If reliable, “Obtain as much information as possible about the actual or potential failure.” Enter on log forms. • Data needed: • Names of Dam • Lat/Lon of Dam • Dam Height • Water height in dam • Volume of water in dam • Length of dam • Condition of the dam • Trees in dam • Bank slide
WFO Operations During Event • Flash Flood Watch (FFA)– “A dam or levee may fail and threaten lives or property, but the threat is not deemed to be imminent, or”. Issuance is from 6 to 48 hours before event. Updated: additional Flash Flood Watches (FFA). • Flash Flood Warning (FFW)– “A dam or levee failure is imminent or occurring”. Updated: Flash Flood Statements • Civil Emergency Messages (CEM)- “For cases when a potential dam failure is a sufficient threat to warrant the evacuation of downstream areas… to convey the urgency of the situation and ensure widest dissemination of information. • Louisiana – Parishes have the authority to issue CEMs. Can Authorize NWS. • Mississippi – Only Mississippi Emergency Management Agency (MEMA) can authorize CEMs. Can authorize NWS.
WFO Operations During Event • Make Contacts… • Dam Owner • State Dam Safety Officials • Supporting RFC • Adjacent and Backup WFO • Meteorologist In Charge (MIC) & Hydro Program Manager • MIC at the WFO designated as the state liaison office • Personnel at regional headquarters
WFO Operations During Event • Issue Flash Flood Statements with Quantitative Forecast Information • (Regional Supplement) -“To ensure that information and data provided by NWS is consistent”. WFOs should utilize the dam failure scenario information in Emergency Action Plans (EAP), if available. • Simplified Dam Break Model • “Dam Failure Rules of Thumb” • NWS “Dam Catalog” • “The WFO should coordinate follow-up watches/warnings/statements with the RFC, dam/levee owner, and/or local emergency management officials and Dam Safety Officials, if possible.”
WFO Operations During Event • If the river reach below the dam is very long, the NWS will need to issue warnings for areas of the lower river or creek basin.
Weather office’s arenot expected to execute dam break models to obtain quantitative information on dam failures. This responsibility falls to the River forecast Center. • WFOs, in collaboration with their servicing RFC, are expected to use the dam failure scenario information from dam EAPs, if available, as the primary source of quantitative information on a flood wave resulting from a dam failure. • If no EAP exists or is available for the dam, dam break models should be used to obtain quantitative information on a flood wave resulting from a dam failure • WFOs should take the lead in collecting information needed by the RFCs to conduct dam break modeling. River Forecast CenterareA of Main responsibility Give Support by Providing Quantitative analysis