Transcript The North Carolina Dam Safety Program

The North Carolina Dam Safety
Program
Our Responsibilities
Administration and enforcement of the Dam Safety
Law of 1967 and the supplementary Administrative
Code
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Inspection program
Permitting program
Enforcement program
Minimum release to maintain aquatic habitat
Emergency Response
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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)
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Interruption of road service, low volume roads (less than 25
vehicles per day)
Economic damage less than $30,000
Class B (intermediate hazard)
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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)
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Loss of human life = Probable loss of 1 or more human lives
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Economic damage - More than $200,000
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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 nonexempt 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:
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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
Earth Dam in Poor Condition
Dam Failures
Overtopping Failure
(reason for design storm requirements)
Dam Failures
“Piping” failure
(inadequate compaction during construction)
Dam Failures
Seepage failure
(flow through embankment or foundation)
Sand boil
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: [email protected]
Web:
http://www.dlr.enr.state.nc.us/pages/damsafetyprogram.html
or just search for “NC Dam Safety” using your
favorite internet search engine.
Questions?