The North Carolina State Dam Safety Program

http://portal.ncdenr.org/web/lr/damsBy: Tami Idol, EI Tami.Idol@ncdenr.gov

Let’s start with the basics

What is the Mission of the Dam Safety Program?

To prevent property damage, personal injury and loss of life from the failure of dams

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Dams Provide Benefits:Dams Provide Benefits:•Water Storage for Municipal and Industrial Use

•Cooling Water for Thermal Power Plants

•Flood Reduction

•Hydroelectric Power

•Minimum Flows to dilute sewage treatment plant discharge

•Storm Water Treatment

•Irrigation Water Storage

•Animal Waste Storage and Treatment

•Recreation

Negative Effects of Dams:•Environmental Alteration in the Impoundment

•Environmental Alteration Downstream

•Displacement of People

•Loss of Cultural and Historical Resources

•Expensive to Construct

•Expensive to Maintain

•Hazard Potential for People and Property Downstream

Jurisdictional DamsJurisdictional Dams

• If Dam is 25 Feet in Height or Greater If Dam is 25 Feet in Height or Greater as Measured from the Highest Point as Measured from the Highest Point on the Crest of the Dam to the Lowest on the Crest of the Dam to the Lowest Point on the Downstream Toe, ANDPoint on the Downstream Toe, AND

• If the Dam has an Impoundment If the Dam has an Impoundment Capacity of 50 Acre-Feet or Greater Capacity of 50 Acre-Feet or Greater as Measured at the Highest Point on as Measured at the Highest Point on the Crest of the Damthe Crest of the Dam

Jurisdictional Dams – Jurisdictional Dams – High Hazard PotentialHigh Hazard Potential

• If Failure of the Dam Could Result in Loss of If Failure of the Dam Could Result in Loss of Human Life or Significant Damage to Property Human Life or Significant Damage to Property Below the Dam regardless of height or Below the Dam regardless of height or impoundment capacity. GS 143-215.25A (a)(6)impoundment capacity. GS 143-215.25A (a)(6)

How is the Dam Safety Program How is the Dam Safety Program Organized?Organized?

7 DENR Regional Offices (RO), 1 Raleigh Central Office 7 DENR Regional Offices (RO), 1 Raleigh Central Office (RCO)(RCO)

Staffing: 9 FTE’s in the RO’s and 9 FTE’s in the RCO49 LQS regional staff are cross trained for Dam Safety, Sediment and Erosion Control, and Mining

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The Dam Safety Program carries out its mission through Four Basic Functions designed to ensure Safe Dams (IREE):

We Perform Dam We Perform Dam InspectionsInspections

We We ReviewReview and Issue Construction and Issue Construction ApprovalsApprovals

We Carry Out We Carry Out EnforcementEnforcement Actions Actions

We Assist with We Assist with EmergencyEmergency Response Response

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State-wide Jurisdictional State-wide Jurisdictional InventoryInventory12-31-201112-31-2011

• 1,118 - High Hazard Dams1,118 - High Hazard Dams

• 245 - Intermediate Hazard Dams245 - Intermediate Hazard Dams

• 622 - Low Hazard Dams622 - Low Hazard Dams

• Grand Total - 1,985 DamsGrand Total - 1,985 Dams

• Includes Includes LowLow and and IntermediateIntermediate hazard dams hazard dams 25 feet in height or larger 25 feet in height or larger andand 50 acre-feet of 50 acre-feet of maximum impoundment capacity or largermaximum impoundment capacity or larger

• Includes high hazard dams of any sizeIncludes high hazard dams of any size

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What would you do?What would you do?

Do Dams Fail in NC?Do Dams Fail in NC?

Well… yes, sometimesWell… yes, sometimes

Historic Dam Failures Historic Dam Failures in North Carolina in North Carolina

Lake Toxaway Dam – 1916Lake Toxaway Dam – 1916Transylvania CountyTransylvania County

• After days of heavy rain from tropical After days of heavy rain from tropical systems, the original Toxaway Dam failed systems, the original Toxaway Dam failed on August 13, 1916. Over 16,000 acre-on August 13, 1916. Over 16,000 acre-feet feet (5.2 Billion Gallons) (5.2 Billion Gallons) of water scoured of water scoured the gorge downstream to bedrock.the gorge downstream to bedrock.

• There was no known loss of human life. There was no known loss of human life. Property damage, however, was Property damage, however, was extensive. extensive.

Bearwallow Dam FailureBearwallow Dam Failure

Bearwallow Dam FailureBearwallow Dam FailureBuncombe CountyBuncombe County

• Failed February 22, 1976Failed February 22, 1976

• Approximately 30 feet high with a 3.5 acre lakeApproximately 30 feet high with a 3.5 acre lake

• Resulted in Resulted in Four DeathsFour Deaths

• There was apparently no engineering There was apparently no engineering supervision during construction of the damsupervision during construction of the dam

• Dam was unknown to regulators prior to failureDam was unknown to regulators prior to failure

• Resulted in the expansion of the Dam Safety Resulted in the expansion of the Dam Safety Program Program

Roxboro Reservoir DamRoxboro Reservoir DamPerson CountyPerson County

Municipal water supply damMunicipal water supply dam

Failed March 7, 1984, as a result of Failed March 7, 1984, as a result of internal erosion (piping) under the internal erosion (piping) under the concrete chute spillwayconcrete chute spillway

Resulted in loss of a 280 acre reservoir Resulted in loss of a 280 acre reservoir and a highway bridge and a highway bridge

No loss of lifeNo loss of life

Roxboro Dam FailureRoxboro Dam Failure

1919

1989 Evans and Lockwood 1989 Evans and Lockwood Dam Failures (Fayetteville)Dam Failures (Fayetteville)

• Several dams in series failed.Several dams in series failed.

• They were unknown to DLR at that time as They were unknown to DLR at that time as they were below jurisdictional sizethey were below jurisdictional size

• Loss of life (2 children)Loss of life (2 children) and property and property damage resulteddamage resulted

• As a result of this event, legislation was As a result of this event, legislation was passed that rendered all high hazard dams passed that rendered all high hazard dams jurisdictional regardless of size jurisdictional regardless of size (remember (remember the 1989 amendment?)the 1989 amendment?)

Damage to Dams, Fall 1999 Damage to Dams, Fall 1999 (Floyd)(Floyd)

• More than 100 jurisdictional dams More than 100 jurisdictional dams had some damage.had some damage.

• 35 dams failed.35 dams failed.

• 16 high hazard dams failed.16 high hazard dams failed.

• There was no loss of life attributed to There was no loss of life attributed to the dam failures.the dam failures.

Damage to Dams fromDamage to Dams from Frances and Ivan 2004 Frances and Ivan 2004

• One failure of a high hazard dam, no loss of life or property damage but a road was overtopped.

• Three high hazard dams damaged so severely they had to be drained and breached.

• Two dams undergoing repairs were damaged.

• One failure of a jurisdictional low hazard dam

• Several small non-jurisdictional dams failed.

• Damage to remaining 300 plus high hazard dams inspected was relatively light, none requiring that the impoundments be drained.

Hope Mills DamHope Mills DamCumberland CountyCumberland County

Municipal recreation damMunicipal recreation dam

Construction completed April, 2009Construction completed April, 2009

Failed June 17, 2010, as the result of a Failed June 17, 2010, as the result of a foundation cutoff failurefoundation cutoff failure

Resulted in loss of reservoir and extensive Resulted in loss of reservoir and extensive spillway damage spillway damage

No loss of lifeNo loss of life

Ironically, this structure was installed as repair Ironically, this structure was installed as repair for failure of the original dam in 2003for failure of the original dam in 2003

Hope Mills DamHope Mills Dam

Hope Mills DamHope Mills Dam

Hope Mills DamHope Mills Dam

Hope Mills DamHope Mills Dam

Hope Mills DamHope Mills Dam

Hope Mills DamHope Mills Dam

Hope Mills DamHope Mills Dam

Hope Mills DamHope Mills Dam

Background of Emergency Background of Emergency Action Planning for DamsAction Planning for Dams

• Since 9/11, requirements by FEMA have Since 9/11, requirements by FEMA have increased priority toward EAPsincreased priority toward EAPs

• EAPs are not required by law in NCEAPs are not required by law in NC

• In order to meet FEMA requirements, NC dam In order to meet FEMA requirements, NC dam safety staff are requesting owners of high safety staff are requesting owners of high hazard dams to have an EPA. Often times hazard dams to have an EPA. Often times this means working 1 on 1 with each owner.this means working 1 on 1 with each owner.

ARE WE DOING IT RIGHT?ARE WE DOING IT RIGHT?

WE NEED YOUR INPUT!!!!!WE NEED YOUR INPUT!!!!!

EMERGENCY RESPONSE

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Emergency ResponseEmergency Response

• NC Dam Safety staff RoleNC Dam Safety staff Role::– Counsel local Incident Commanders as to level of Counsel local Incident Commanders as to level of

emergency in a dam incident situationemergency in a dam incident situation– Assist with interpretation of the EAP (if one exists)Assist with interpretation of the EAP (if one exists)– Advise the Local Incident Commander concerning the Advise the Local Incident Commander concerning the

need to evacuateneed to evacuate– Assist owner of dam and local responders in preparing an Assist owner of dam and local responders in preparing an

EAPEAP

• All Dam Safety RCO staff are SERT (State Emergency All Dam Safety RCO staff are SERT (State Emergency Response Team) members:Response Team) members:– Serve in the infrastructure disciplineServe in the infrastructure discipline– Man the state Emergency Operations Center (EOC) when Man the state Emergency Operations Center (EOC) when

it is activated during any situation which may threaten it is activated during any situation which may threaten damsdams

• All LQS staff are on duty 24-7 in the event of a dam All LQS staff are on duty 24-7 in the event of a dam emergencyemergency– 18 two-person inspection teams from the RO’s available18 two-person inspection teams from the RO’s available– Plus RCO staff rotates on 8 to 12 hours shifts at the EOC Plus RCO staff rotates on 8 to 12 hours shifts at the EOC

during activationduring activation3535

FEMA requires all states to adhere to:

National Incident Management System (NIMS)

Incident Command System(ICS)

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3737 Implement Document Procure Pay & Audit

Emergency Operation Emergency Operation CenterCenter800-858-0368800-858-0368

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Emergency Action Plans Emergency Action Plans (EAPs)(EAPs)• An Emergency Action Plan (EAP) outlines An Emergency Action Plan (EAP) outlines

procedures to minimize risks to life and procedures to minimize risks to life and property when the integrity of a dam may be property when the integrity of a dam may be in jeopardy.  in jeopardy. 

• Two parts to the EAP equation:Two parts to the EAP equation:– The EAP shall consider all potential emergency The EAP shall consider all potential emergency

situations, both natural and manmade. situations, both natural and manmade. Owners Owners & engineers responsibility& engineers responsibility

– shall identify appropriate responses. shall identify appropriate responses. Local Local responders responsibilityresponders responsibility

Planning, Training, and ExercisesPlanning, Training, and ExercisesAll Hazard focused plansAll Hazard focused plansCollaborationCollaborationPractice and experiencePractice and experience

CollaborationCollaboration• Collaboration between NC Dam Collaboration between NC Dam

Safety and NC Emergency Safety and NC Emergency Management , Flood Plain Mapping Management , Flood Plain Mapping Program:Program:

• Producing a web based fill in the blank EAP for Producing a web based fill in the blank EAP for owners based upon the current template.owners based upon the current template.

• Flood mapping may be completed by the Flood mapping may be completed by the owners engineer orowners engineer or

• based upon a risk assessment, one of 3 levels based upon a risk assessment, one of 3 levels of analysis, Bronze, Silver or Gold level of analysis, Bronze, Silver or Gold level mapping will be completed through mapping will be completed through collaboration and provided to responders.collaboration and provided to responders.

Example Vicinity MapExample Vicinity MapBRONZE

SILVERSILVER• Medium risk high hazard damsMedium risk high hazard dams

• Possibly using a method recently beta Possibly using a method recently beta tested by NC Dam Safety and NCFPMPtested by NC Dam Safety and NCFPMP

• This method produces a GIS shapefile, just This method produces a GIS shapefile, just like the GOLD level would, with slightly like the GOLD level would, with slightly less effort in data collection and input. less effort in data collection and input. This output will show more structures in This output will show more structures in the flooded area than a more detailed the flooded area than a more detailed analysis.analysis.

GOLDGOLD

• High risk high hazard damsHigh risk high hazard dams

• Using a full scale HEC RAS analysis.Using a full scale HEC RAS analysis.

• This method produces a GIS shapefile This method produces a GIS shapefile as well. With more detail and effort as well. With more detail and effort going into data collection, the results going into data collection, the results will be closer to what reality would will be closer to what reality would be.be.

GIS CapabilityGIS Capability

Open Troublesome Creek EAP mapsOpen Troublesome Creek EAP maps

What does the Dam Safety program need?What does the Dam Safety program need?

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We need more EAP’sWe need more EAP’s

• EAP’sEAP’s for high hazard dams !!!!! for high hazard dams !!!!!– Only 32% of high hazard dams in NC have EAP’s on file Only 32% of high hazard dams in NC have EAP’s on file

todaytoday

• The problem - No statutory authority to require The problem - No statutory authority to require themthem

• How do we procure them now? How do we procure them now? – Through requests to dam ownersThrough requests to dam owners– By stipulation in approvalsBy stipulation in approvals– Local responders could be invaluable in getting the ball Local responders could be invaluable in getting the ball

rollingrolling

• Nothing is more valuable during a dam incidentNothing is more valuable during a dam incident– Emergency Management uses the EAP to develop Emergency Management uses the EAP to develop

evacuation plansevacuation plans4848

St. Francis Dam - 1928St. Francis Dam - 1928

• Estimated 450 Estimated 450 fatalitiesfatalities

• 1200 buildings 1200 buildings destroyed or destroyed or damageddamaged

• 24,000 acres 24,000 acres of agricultural of agricultural land destroyedland destroyed

Teton Dam Teton Dam 11:20 AM June 5, 197611:20 AM June 5, 1976

Teton Dam, Teton Dam, 11:20 AM June 5, 197611:20 AM June 5, 1976

Teton Dam, Teton Dam, 11:30 AM June 5, 197611:30 AM June 5, 1976

Teton Dam, Teton Dam, ~11:40 AM June 5, 1976~11:40 AM June 5, 1976

Teton Dam, Teton Dam, ~11:50 AM June 5, 1976~11:50 AM June 5, 1976

Teton Dam, Teton Dam, ~11:55 AM June 5, 1976~11:55 AM June 5, 1976

Teton Dam, Teton Dam, Early afternoon June 5, 1976Early afternoon June 5, 1976

Teton Dam Teton Dam

• 11 human 11 human fatalities & fatalities & 13,000 head of 13,000 head of cattlecattle

• Original cost of Original cost of construction construction $100 Million$100 Million

• US Gov’t paid US Gov’t paid over $300 over $300 Million in claims Million in claims related to the related to the failurefailure

Just after midnight nearly Just after midnight nearly thirty years ago on thirty years ago on November 6, 1977, the November 6, 1977, the Kelly Barnes Dam Kelly Barnes Dam failed, releasing 176 failed, releasing 176 million gallons of million gallons of water just above water just above Toccoa Falls College Toccoa Falls College campus in northern campus in northern Georgia. Thirty-nine Georgia. Thirty-nine people lost their lives. people lost their lives. Sadly, twenty of those Sadly, twenty of those deaths were children.deaths were children. Video

Aerial view of Kelly Barnes Lake area -- looking downstream. Washed out dam is near shadow area near upper edge of picture. Additional outflow occurred at white area near right edge of picture.

Failure of this dam prompted President Carter to begin the National Dam Safety Program.

Kelley Barnes Dam, Georgia

AftermathAftermath$30 million $30 million damagesdamages

Photographs and descriptions courtesy of Vernon B. Sauer, USGS retiree and a member of the Federal Investigative Board

that examined the Kelly Barnes Dam failure.

Tami Idol, EITami Idol, EI

NC Assistant State Dam Safety NC Assistant State Dam Safety EngineerEngineer

Tami.idol@ncdenr.gov

919-707-9220919-707-9220