DSWR Safety Engineering Program. Core Purpose: Protect human life, health & property from dam failures. Ohio Dam Safety Responsibilities

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1 Ohio Department of Natural Resources Division of Soil and Water Resources Dam Safety Meeting Rodney Tornes & Martin Joyce TAKE DAM SAFETY LIGHTLY Dam Safety Overview Ohio Dam Safety Laws, Rules, Responsibilities Dam Classification How Dams Work Dam Failures How & Why Impacts of Dam Failures DSWR Safety Engineering Program Core Purpose: Protect human life, health & property from dam failures Laws & Rules Program authority founded in both ORC and OAC Law - Ohio Revised Code Sections Construction Permits Surety Bonds for Construction Permits Periodic Inspections; Exemptions; Repairs & Modifications; Emergency Authority; Owner Responsibilities Annual Fee Inspection Exemptions Right of Entry Penalties Rules Ohio Administrative Code Chapters 1501: thru 1501: Provides more detail of the law Ohio Dam Safety Responsibilities Per Ohio laws - dam safety is a shared responsibility between the dam owner & Division of Soil & Water Resources (DSWR) 1

2 Owner Responsibilities Per ORC (E), the Owner of a regulated dam shall: Monitor, maintain & operate their dam safely, in accordance with state rules, terms & conditions. Promptly notify the DSWR & other authorities of conditions threatening the safety of the structure and take actions to safeguard life, health, & property DSWR Responsibility Implement Dam Safety Program Periodic safety inspections Five-year periodic inspections Evaluate condition, d/s hazard, & owner s safety program Notify the Chief of DSWR in writing of a change in ownership prior to exchange of the property Dam Safety Program Periodic safety inspections Evaluate condition, d/s hazard, & owner s safety program Five-year periodic inspections Repairs and modifications Review & oversight of repairs and modifications Dam Safety Program Periodic safety inspections Evaluate condition, d/s hazard, & owner s safety program Five-year periodic inspections Repairs and modifications Review and oversight of repairs and modifications Construction permits Issue permits for new dams and increases in size Dam Safety Program Periodic safety inspections Evaluate condition, d/s hazard, & owner s safety program Five-year periodic inspections Repairs and modifications Review and oversight of repairs and modifications Construction permits Issue permits for new dams and increases in size Enforcement Authority to compel corrective action through the courts Dam Safety Program Periodic safety inspections Evaluate condition, d/s hazard, & owner s safety program Five-year periodic inspections Repairs and modifications Review and oversight of repairs and modifications Construction permits Issue permits for new dams and increases in size Enforcement Authority to compel corrective action through the courts Emergency response Authority to require and to take immediate action Emergency Actions Plans required for Class I, II, III Dams 2

3 Dam Classification regulated dams Class I Dams in Ohio Class I * Loss of Life homes, businesses Federal Dams (USACE & USDI) 31 State Regulated (Large Dams) 144 > 60 feet high > 5000 acre-feet storage 237 State Regulated (Small Dams) Large Dam dam height greater than 50 feet or normal pool storage greater than 1000 acre-feet Dam Classification Class II * Loss of High-Value Property *Damage to businesses & class I, II, III dams *Floodwater damage to homes * Damage to State and Interstate Roads > 40 feet high > 500 acre-feet storage Dam Classification Class III * Loss of Property - Agr. structures, garages, exempt dams * County, Township, & City Roads > 25 feet high > 50 acre-feet storage Dam Classification Class IV Dam and lake larger than Exempt Dams Exempt from ODNR Regulation Based on Size Volume of Water at Highest Level feet high & acre-feet storage No significant downstream hazard impact Height Volume Reference Less than 6 ft. Unlimited - 6 to 10 ft. 15 to 50 9 feet in height, 10-acre lake acre-feet Unlimited Less than 15 acre-feet 15 feet in height, 2.5-acre lake 3

4 Dams Exempt Based on Ownership: Dams Regulated by the Division of Soil & Water Resources Federal & Many Mining Related Dams Class I Class II Class III How Dams Work How dams work: Retain a pool and pass floods Parts & Functions (Sketch) 4

5 Dam Failures Dam Failure Who Done It? How do dams fail? 1. Overtopping 2. Spillway Erosion/Collapse 3. Embankment/Foundation Seepage 1. Overtopping Undersized spillway/not enough freeboard Blocked spillway Low area on the crest Low area on the crest Upground Reservoir accidentally overfilled 5

6 Spillway Undersized/Not Enough Freeboard Spillway Too Small - Near Failure Blocked Spillway Low Area on the Crest Low Area on the Crest

7 Taum Sauk Reservoir in Missouri 2005 Accidentally Overfilled 2. Spillway Erosion/Collapse Deterioration of Materials Rusting metal Cracking concrete Loss of joint material Loss of support Poor design/construction Failure

8 Common Seepage Paths 3. Embankment/Foundation Seepage Seepage through the embankment Seepage under or around the dam Seepage along or under the spillway Seepage - Boil at Toe of Dam Sinkhole 8

9 Kaloko Dam Failure in Hawaii Impacts of Failures Hadlock Dam in New York South Fork Dam Failure in Johnstown, PA killed 2209 people Findlay Area Early 1980s 9

10 South Fork Dam Johnstown, PA Downstream Damage Johnstown was located approx. 14 miles downstream of South Fork Dam. 10