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Learn about the administration and enforcement of the Dam Safety Law of 1967, inspection, permitting, and enforcement programs, emergency response, jurisdictional dams, hazard classifications, and our regulatory authority.
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Our Responsibilities • Administration and enforcement of the Dam Safety Law of 1967 and the supplementary Administrative Code • Inspection program • Permitting program • Enforcement program • Minimum release to maintain aquatic habitat • Emergency Response • Dam Safety Emergencies can happen any time • Hurricane Season June through November • Our role is officially as technical advisor to professional “first responders” • We are often the first agency to know about and respond to a potential dam safety emergency • Owner /engineer education and public awareness
By What Authority Do We Operate • NCGS 143-215.24 (The Dam Safety Law of 1967). Declaration of purpose. - It is the purpose of this Part to provide for the certification and inspection of dams in the interest of public health, safety, and welfare, in order to reduce the risk of failure of dams; to prevent injuries to persons, damage to downstream property and loss of reservoir storage; • and to ensure maintenance of minimum stream flows of adequate quantity and quality below dams.
Where are we located?We have seven regional offices and a central office in Raleigh.
Jurisdictional Dams • IF the dam is 15 feet in height or greater as measured from the highest point on the crest of the dam to the lowest point on the downstream toe, • AND the dam has an impoundment capacity of 10 acre-feet or greater at crest of dam elevation • BUT, Dams that are classified high hazard are under the jurisdiction of the law regardless of height and impoundment capacity.
.0223 DAM HEIGHT AND STORAGE DETERMINATION (a) For the purpose of determining size classification, the height of a dam shall be measured from the highest point on the crest of the dam to the lowest point on the downstream toe. (b) The total storage capacity of a dam shall be that volume which would be impounded at the elevation of the highest point on the crest of the dam.
Hazard Classifications • Class A (low hazard) • Interruption of road service, low volume roads (less than 25 vehicles per day) • Economic damage less than $30,000 • Class B (intermediate hazard) • Damage to highways, Interruption of service (25 to less than 250 vehicles per day) • Economic damage - $30,000 to less than $200,000 • Class C (high hazard) • Loss of human life = Probable loss of 1 or more human lives • Economic damage - More than $200,000 • Probable loss of human life due to breached roadway or bridge on or below the dam = 250 or more vehicles per day • Environmental damage also considered (cost of cleanup)
How do we do our job? Inspections Permitting Enforcement
How often do we inspect dams? • NC Administrative Code (Title 15A Subchapter 2K) requires inspection of Class A (low hazard) and Class B (intermediate hazard) once every five years. • NC Administrative Code requires inspection of Class C (high hazard) dams once every two years; however current Land Quality Section policy calls for inspection of Class C dams once a year. • There are currently about 5,400 dams on the state inventory.
Permitting • The Division of Land Resources is responsible for issuance of approvals to construct, repair, modify, or breach any non-exempt dam. All permitting is processed through the Raleigh Central Office, not the regional offices. • Application processing fees are collected for construct, modify and breach project submittals as authorized by the state Dam Safety statute. • General permits required for a dam project: • Dam Safety Approval (to construct, repair, modify or breach) • Sediment and Erosion Control Approval (through regional LQS office or approved local program) • USA-COE 404 Permit (wetland and stream destruction) • NCDWQ 401 Certification (accompanies all 404 permits) • NCDWQ Approval of stream buffer impact (in certain river basins) • Dam Safety Approval to Impound (upon project completion)
Enforcement • Criminal Penalties (administered through the NC court system): not less than $100 and not more than $1,000 per violation which can be assessed per day for willful violation. • Civil Penalties (assessed by the NCDENR Secretary): not less than $100 nor more than $500 per violation which can also be assessed per day for willful violation. • Injunctive Relief (administered through the NC court system): restrains the violation by court order and/or requires corrective action. • All of these actions are normally initiated by issuing a Dam Safety Order (DSO) from the Land Resources Division Director under authority of the NC Administrative Code. DSO’s are usually preceded by inspection letters and Notices of Deficiency (NOD’s).
SECTION .0200 - OBTAINING APPROVAL FOR DAM CONSTRUCTION, REPAIR, OR REMOVAL • The design, preparation of the drawings and specifications, inspection of the work performed on the dam, and certification that the dam was constructed, repaired, altered, or removed according to the approved plans and that the dam or its remains are safe shall be performed by an engineer registered in North Carolina and shall bear his professional seal.
What Is Considered Maintenance? • Mowing • Removing trees and bushes up to 6 inches in diameter (strongly recommended) • Minor replacement of rip rap • Releasing impounded water as through an existing outlet works or temporary siphon erected without excavation. • Oiling valve operators or minor equipment repairs.
Repairs Requiring A Plan • Riser replacement • Filter drain replacement • Slope repairs • Removing trees over 6 inches in diameter • Spillway repairs, replacements, or expansions • Anything requiring excavation into the dam
Rights of investigation, entry, access, and inspection (§ 143-215.37) Inspectors have the right to make entry onto property to perform inspections of dams at reasonable times. We welcome the owner of the dam being inspected to accompany us on the inspection. If the owner‘s telephone number is in our records, it is our policy to make an attempt to contact the owner prior to inspection.
Earth Dams • Majority of Dams in North Carolina • Safe if properly designed, constructed, and maintained • Designed so as not to overtop
Dam Failures Overtopping Failure (reason for design storm requirements)
Dam Failures “Piping” failure (inadequate compaction during construction)
Dam Failures Sand boil Seepage failure (flow through embankment or foundation)
Emergency Action Plans (EAP’s) Required for high hazard dams Recommended for intermediate hazard dams Critical document to have available during a dam safety emergency (contacts and procedures) Contact Tami Idol in the Raleigh Central Office for additional information
Contact Information Bill Denton, EIT, Assistant Dam Safety Engineer Telephone: (919) 733-4574 E-mail: bill.denton@ncdenr.gov Web: http://www.dlr.enr.state.nc.us/pages/damsafetyprogram.html or just search for “NC Dam Safety” using your favorite internet search engine.