Water Power and Dam Construction. Issue September 2010
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52 SEPTEMBER 2010 INTERNATIONAL WATER POWER & DAM CONSTRUCTION
RESEARCH
r Educate and provide knowledge necessary to manage the risks asso-
ciated with dams.
r Identify the areas where additional research may improve knowl-
edge of potential failure modes and identify ways to prevent or
mitigate their development.
r Identify ways to ensure that the knowledge of the past is available
for the future.
r Develop a plan to ensure the continuation of global communica-
tion, co-ordination and collaboration.
To further its goals of sharing important dam safety case studies,
CEATI has kindly allowed IWP&DC to give an insight into the infor-
mation exchange which took place at the workshop in 2009. A selec-
tion of case studies below illustrates the most common causes of dam
failures – ranging from liquefaction, piping and seismic deformation,
plus operation controls and human interaction.
ARAPUNI DAM, NEW ZEALAND
Arapuni dam is a 64m high curved concrete gravity structure on the
Waikato river in the North Island of New Zealand. It was completed in
1927 to form a reservoir for the 186MW hydroelectric power station.
A series of foundation leakage events have occurred since water
was rst impounded in 1927. Several remedial techniques were tried
over the years, including a grout curtain in 1930 and bitumen grout-
ing from 1935 to 1942. Overall there was no long-term effect on
seepage ows.
In 1995 eight observation well holes were drilled into the foun-
dation to provide the opportunity for uplift measurement beneath
the dam. Two of these eight holes intersected high water pressures
and each owed at several hundred litres per minute after drilling.
The high-pressure ow was encountered at a depth that coincided
with one of the sub-vertical fractures in the dam foundation recorded
during dam construction. Dirty water observed in one of the holes
indicated that some foundation material may have eroded.
From 1995 to 1999 pressures and ows increased slightly. One
of the two high pressure holes was used as a relief drain through-
out this period, while the other monitored pressure in the fracture.
During 1999-2000 there was a steep increase in pressure and ow.
In September 2000, solid material (clay and bitumen particles up to
20mm in diameter) was observed to be exiting the relief drain. If ero-
sion migrated along the line of the fracture and downstream of the
two drill holes, it could have had major consequences for the integrity
of the dam.
While an immediate action involving grouting the two high pres-
sure holes could have been carried out in September 2000, this was
not considered the best solution. Clearly an eroded path through the
dam foundation had developed, but little was known about the seep-
age path, including the size of the void, nature of eroding material,
the source of seepage water or the path of the leak.
Grouting at this stage would have given an unknown result as to the
effectiveness of the grouting. Excessive grouting pressures were also
considered to have the potential to initiate blowout of the remaining
fracture inll between the holes and the downstream face.
Therefore it was considered more prudent to investigate the leak and
treat it when better understood. The investigations would be under-
taken with the full reservoir in place but with the option to grout the
two drill holes as a contingency should the dam’s condition become
unacceptable and action be necessary to stem the leakage ow.
In October 2001 it was decided that sufcient investigation infor-
mation had been gathered to identify the leakage path and success-
fully ll the void. This well engineered operation was programmed
for early December 2001.
It is now evident that all the previous incidents dating back to 1927
were related to piping within, and erosion of, the weak clay inll-
ing the defects within the volcanic ignimbrite rock foundation. The
various grouting works only lled voids where the vertical drillholes
connected to open voids in vertical joints, leaving other leakage paths
open. The most likely cause of seepage reduction in the intervening
time is considered to be migration of fracture inll material gradually
sealing seepage exit points.
While the 2001 grouting had successfully lled the void identied
in the fracture inll, there were signicant quantities of erodable clay
inll remaining in the foundation. Furthermore, open voids were
identied by subsequent investigations in other fractures in the dam
foundation. Based on previous history, future incidents with similar
potential consequences were considered likely.
A targeted and cost effective cut-off wall project to reduce the risk
of further piping incidents was implemented by the owner, from
2005-7. Operation of the reservoir was not affected and electricity
generation also continued during the cut-off works.
Misinterpretation
Gradually declining seepage from the 1950s was misinterpreted at
Arapuni dam up until 2000. It was not until the incident occurred
that detailed research of construction and early incident records was
carried out. The seepage history was not taken into consideration
when the 1995 drill holes were planned. No ltering of the drains was
applied and considerable joint inll material would have eroded over
the following ve years. The frequency of monitoring readings prior
to 2001 had been insufcient to identify sudden seepage changes that
indicated the erosion process of nes migration with blocking and
unblocking along the seepage paths
LOWER SAN FERNANADO DAM, US
Lower San Fernando dam was part of the Lower Van Norman com-
plex and Los Angeles aqueduct system in the US. The dam was an
earth embankment approximately 43m high at its maximum section.
CEATI International
Based in North America, CEATI International is a user driven multi-national
development and exchange programme for utilities as well as select
government agencies. Its Dam Safety Interest Group is part of a larger
CEATI hydro programme which brings together over 60 of the world’s leading
hydroelectric utilities. Goals and objectives include technical networking,
best practices exchange as well as research and development project cost
sharing opportunities on a practical scale such that deliverables have an
immediate impact for participants. Hydro generation capacities of participating
companies range from under 50MW to over 35,000MW.
As all projects are sub-contracted to outside rms, CEATI is not bound to
work with a single research organisation, providing great exibility such that
all projects are undertaken by the most appropriate rms, including those
entities participating in the programme.
Above: Arapuni Dam, New Zealand, looking West
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54 SEPTEMBER 2010 INTERNATIONAL WATER POWER & DAM CONSTRUCTION
RESEARCH
It was constructed by the hydraulic ll method in 1912.
The foundation in the channel section and lower portions of the
abutment rests on alluvium consisting of stiff clay with lenses of sand
and gravel. The alluvium has a maximum thickness of about 11m.
Underlying this and forming the upper parts of the abutments are
shales, siltstones and sandstones.
On 9 February 1971 an earthquake of magnitude 6.6 on the Richter
scale caused a major slide on the upstream slope of the dam. The dam
did not fail or release the contents of the reservoir, which was imme-
diately drawn down. The downstream population of 80,000 people
was evacuated to a safe elevation over a period of four days.
The possible occurrence of the slide 25 seconds after shaking had
stopped led to multiple interpretations of the possible cause of failure.
Field investigations found a highly disturbed zone of hydraulic ll in the
lower 6m of the dam that liqueed and sheared. The dam above this
zone remained largely intact moving in large undisturbed blocks.
One explanation has suggested the increase in pore pressure in the
hydraulic ll corresponded to a loss of strength in those soils. As a result,
stronger zones accumulated the stresses the weaker zones were carrying,
eventually exceeding their strengths at which point failure occurs.
The timing has been suggested to relate to the ow of water that
occurs due to the excess pore pressure and the associated hydraulic
gradient. It was hypothesised that the ow of water caused a progres-
sive loosening and loss of strength in the initially stronger but dilative
starter dikes leading to the failure.
Other explanations of the delayed failure mechanism have sug-
gested the possibility of a progressive failure where a lower block
fails leading to an increase in driving stresses on the remaining in-tact
slope and a subsequent failure of the next up-slope block.
The experience at Lower San Fernando is a critical case history
on dams and liquefaction, and forms the basis of understanding
residual strengths of soils subjected to liquefaction. Loose material
within foundations or embankments will not perform well during
earthquakes. Dams with potentially liqueable material and subject
to earthquake shaking need careful evaluation.
The dam and reservoir were abandoned. Other facilities were con-
structed in the complex to replace the storage facility.
BELCI DAM, ROMANIA
Limited hydrological data prior to construction had a detrimental impact
on the Belci dam on the Tazlaur river, near Slobozia in Romania. This
18.5m high, 432m long earthen structure was built in 1962. However
hydrological measurements for the estimation and pre-calculation of
design oods had only been collected from a gauging station 10km
upstream from the dam site for ten years prior to construction.
During its 29 years of operation, oods occurred on Tazlau river
with peak values much more than those estimated at Belci dam. On 7
July 1970 a peak inow of 980m
3
/sec caused overtopping of the dam
and part of the left wing was eroded. After further oods on 29 May
1971 and in August 1979 with peak values of 890m
3
/sec and 855m
3
/
sec respectively, a new calculation for the design oods was commis-
sioned. However the spillway capacity was never changed because at
the same time the risk classication of the dam was reduced.
On 28 July 1991 heavy rainfall occurred. Failure of the main telephone
lines meant that no prediction of ood warnings could be sent from the
upstream catchment areas to the dam site. Power failure at the site also
meant that the bottom outlet could only be opened 40cm. Emergency
power was also unavailable and the gates could not be opened manually
as timber and debris were blocking the bottom outlet.
At 02.15am on 29 July the dam began to overtop and the reservoir
was emptied by 07.15am. Twenty ve people were killed by the ood
wave caused by the dam break and 119 houses were destroyed.
The peak inow of 1200m
3
/sec was lower than the later estimated
1-in-100-year ood of 1515m
3
/sec. The initial dam break occurred at
the same point where the dam had been affected by erosion in 1970.
Post-failure measurements of the intact dam crest near this initial
break showed that the repair works had produced the effect of a
natural overow section. A cable trench that had been dug along the
dam crest also had a negative and accelerating inuence with regards
to the process and dynamics of the breach formation.
The dam has not been reconstructed.
ZIPINGPU DAM, CHINA
On 12 May 2008 the epicentre of an earthquake, measuring 8.0 on
the Richter scale, was located only 17km away from the Zipingpu
dam. Located on the Minjiang river, in China’s Sichuan Province,
the 156m high CFRD survived the strong earthquake but suffered
considerable damage, especially on the upper part of the structure.
During the earthquake acceleration at the dam crest reached 2.0g.
As the dam design is based on the assumed peak ground acceleration
(PGA) of 0.26g, the actual PGA is far beyond the intensity accepted
by the design.
During the earthquake signicant deformation occurred at the
dam. Immediately afterwards there was obvious settlement of the
dam crest in the riverbed section. The maximum settlement value was
683.9mm, located at the river centre section. After the main earth-
quake, the observed settlement of dam crest still developed but the
rate dropped rapidly and stabilised on 22 May.
The strong earthquake had damaged the concrete face slab, which
included cracks and ruptures. Spalling of the concrete was also
noticed. As the maximum dynamic response of the dam occurred at
the dam crest, the earthquake caused many cracks and ruptures of
the parapet wall.
Below: Damage at the crest, downstream edge, of Zipingpu Dam, China
Above: Damaged vertical joint in the concrete Face at Zipingpu CFRD
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56 SEPTEMBER 2010 INTERNATIONAL WATER POWER & DAM CONSTRUCTION
RESEARCH
Immediately after the earthquake, a dam safety expert group was dis-
patched by the Ministry of Water Resources to check the dam status.
The damaged spillway tunnels were repaired and the reservoir level
controlled and lowered. The repairs to the ruptured concrete face slab
and separation of the face slab and rockll began on 30 May 2008.
Stable and safe
Although the Sichuan earthquake had produced severe damage to the
dam, it is still structurally stable and safe. The performance of Zipingpu
has demonstrated the safety features of CFRD during such an event.
As there is no serious slide of the downstream slope, it shows that the
two-stage slope design (1:1.5 for the upper part slope and 1:1.4 for the
lower part slope) for the downstream slope is appropriate.
Although the waterstop system was not seriously damaged and
there was no significant increase in dam leakage at Zipingpu, it
should be noticed that this is one of the vulnerable parts of a CFRD
upon extreme loading.
STEINAKER DAM, US
Located in Utah, US the 49m high Steinaker dam was completed
in 1961. In November 1962, a sinkhole area, approximately 3m in
diameter and 2m deep, appeared on the downstream face of the dam,
47m downstream from the crest centreline.
The engineers who examined the sinkhole concluded that satu-
ration collapse had occurred. The supposedly benign sinkhole was
lled. Additional depressions were reported in this area in June and
October of 1963. The sinkhole was again backlled. No further sub-
sidence was reported at this location.
In August 1965 a second sinkhole was reported, approximately 6m
in diameter and 1.5m deep, 45m downstream from the centreline.
An engineer examining the site judged that the dam was in no danger
of failing, but recommended a remedial grouting programme which
was carried out on the left abutment between December 1965 and
April 1966.
In 1992, US Bureau of Reclamation decided to modify Steinaker
dam to rectify a seismic stability issue. It was also recommended that
investigations were carried out to assure that the core’s integrity had
not been compromised by the internal erosion. Three lines of three
boreholes were drilled in the vicinity of the sinkholes, and cross-hole
tomography was performed from the boreholes in an attempt to locate
and determine the size of any voids that might remain. The tomogra-
phy results were inconclusive, but borehole completions prior to testing
did provide some indication that voids might still be present.
The sinkholes are believed to have formed by the following mechanism:
r Seepage travelled through left abutment bedrock fractures and owed
through pervious alluvial foundation materials, through Zone 3 shell
material, and through the gravel envelope surrounding the toe drain.
r Voids in the gravel envelope and between cobbles in the Zone 3
were large enough to provide an unltered exit for the ne-grained
foundation alluvial material, and were extensive enough to store
some of the eroded material.
r A large tear in the toe drain also provided an unltered exit point
and a means to remove foundation alluvial material.
r The constant seepage ow carried the alluvial material with it, even-
tually forming a large void beneath the Zone 3 material.
The sinkhole mechanism by itself was unlikely to have resulted in
dam failure. However, if the abutment had not been grouted, it is pos-
sible some of the joints or fractures could have directed seepage water
along the embankment/bedrock contact, causing erosion at contact
points, possibly bringing full reservoir head closer to the unltered
exit points, increasing gradients and initiating a pipe completely along
the embankment/foundation contact. The pipe would then transmit
higher-velocity seepage, rapidly increase erosion, and eventually initi-
ate a dam breach.
Engineers on the project warn that there should be a greater aware-
ness of potential stiffness changes beneath a planned toe drain, so
that differential settlement from embankment loading does not tear
openings in the drain pipe. At the project the original toe drain was
replaced with a perforated PVC pipe, embedded in a sand and gravel
mixture having a gradation designed to lter the ne-grained founda-
tion materials. The lter material was also placed as a chimney drain
on the upstream face of the excavation slope.
SALUDA DAM, US
Seismic remediation using a back-up dam was a milestone project
carried out at the Saluda dam in the US. It was performed to prevent
reservoir releases due to seismic loading, and subsequent potential
liquefaction of the original dam.
Above: RCC placement at Saluda Dam
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58 SEPTEMBER 2010 INTERNATIONAL WATER POWER & DAM CONSTRUCTION
RESEARCH
Originally constructed from 1927-30, Saluda Dam is owned and
operated by South Carolina Electric & Gas Company. It is a 64m
high, 2388m long semi-hydraulic earthll structure made from locally
obtained silty clay and sandy silt. This construction method resulted
in a relatively low density embankment with extensive zones of inter-
nal saturation.
In the 1980s, a series of geotechnical investigations were under-
taken to assess the safety of the original dam, particularly under seis-
mic loading. Analysis indicated that the dam could be susceptible
to liquefaction failure during large earthquakes. A major portion
of the embankment could fail if an earthquake similar to the 1886
Charleston event were to occur again.
It was decided that the dam required remediation of some kind to
resist such an event. The primary objectives of this were to prevent
catastrophic ooding downstream of the dam, and to ensure safe
shutdown of the facilities, including lowering the water level of Lake
Murray in a controlled manner.
After considerable evaluation of alternatives, the remediation con-
cept was developed as a backup dam immediately downstream of
the existing earth embankment. The original dam remains in place
and functions as the primary water impounding structure for Lake
Murray. The backup dam will become a water retention structure if
the original dam ever fails. It is also the rst time a dam of this size has
been so extensively modied under a virtually full reservoir head. This
minimised economic and environmental impacts to the local area.
Approximately ve million cubic yards of rock ll and aggregate
were required to construct the backup dam, which consists of a com-
bination RCC gravity section and two rockll embankments. These
required an on-site rock quarry, with a large crushing plant, stock-
piles, and concrete mixing facilities. In order to ensure the safety of
the original dam during construction, an extensive dewatering pro-
gramme was required.
The backup dam itself had two seismic instruments installed, one
in the foundation and another on the crest of the RCC section. New
vibrating wire piezometers were installed in the foundation of the
RCC section to monitor uplift pressures should the dam ever be called
upon to retain Lake Murray. A network of reference benchmarks
were installed on site, and survey monuments were installed on the
crest of the backup dam to allow precise deformation and settlement
measurements. The back-up dam was completed in 2005.
MATAHINA DAM, NEW ZEALAND
Severe internal erosion damage with crest subsidence on the left abut-
ment followed an earthquake at New Zealand’s Matahina dam on 2
March 1987. The epicentre of the earthquake was only 23km from the
dam, and emergency drawdown of the reservoir prevented failure.
The 85m high dam is located on the Rangitaiki river in the North
Island. This earthquake-induced internal erosion damage needs to be
understood in context of an earlier incident at the dam.
During the nal stages of lake lling at the construction site in
January 1967, a large temporary increase in ow was observed from
the drainage blanket. Approximately two weeks later an erosion
cavity appeared on the crest downstream of the core in the right abut-
ment area. It was found that the core had cracked adjacent to a 1.8m
wide bench in the abutment at a depth of 12m below the crest. It was
concluded that the erosion had occurred where a large boulder had
been placed against the abutment creating an unprotected exit. The
area was repaired and performed satisfactorily until 1987.
After the earthquake the initial damage appeared minor. There was
transverse cracking at each abutment, minor spreading of the crest,
moderate deformation of the rockll and a small initial increase in
ow from the earth dam drainage blanket.
Although observations indicated the damage was supercial, in
light of the 1967 incident, a comprehensive monitoring and investi-
gation programme was initiated. It was concluded that core cracking
and internal erosion had occurred but that it was not known if this
was caused by the earthquake or predated it. On 17 December 1987,
while investigations were in progress, an erosion cavity appeared at
the surface above the area of damaged inner transition. This was con-
rmation that internal erosion had occurred and was continuing.
Over the next few days, the lake was lowered in a number of stages
as uctuating piezometer measurements indicated continuing erosion.
It was concluded that cracking of the core and inner transition had
occurred prior to the earthquake and probably during lake lling in
1967. (A few hours after the 1967 leakage ows had peaked, a second
but smaller peak occurred. A possible explanation for the second peak
is that it was due to cracking and leakage on the left abutment).
The dam was repaired in 1988 but did not address the prevention
of internal erosion in the dam away from the dam abutments. This
was rectied during major re-building of the dam in 1996-98.
Lessons learned from the experiences at Matahina dam are sum-
marised here:
r The availability of design, construction and performance informa-
tion, together with personnel familiar with it was essential in the
earthquake emergency and the investigations that followed.
r The six-yearly dam safety examinations provided the means for a
new generation of engineers to become familiar with the dam. The
dam safety report completed before the earthquake correctly iden-
tied the main features of the dam’s subsequent post-earthquake
behaviour.
r As the dam was operated below its normal generation level after the
earthquake the monitoring information from the 1967 lake lling
was the only precedent information available and demonstrated the
importance of these records.
r Internal erosion can be a rapid process or a slow process over
many years.
r At intensities above MM7 many people are affected by shock,
including dam operational staff. Shock may prevent staff from
carrying out planned post earthquake procedures. Relief staff are
required on site to continue dam inspections and operations.
r Duplicate power sources for the spillway gates are essential and
have become commonplace. At Matahina external power was una-
vailable and the station generators had tripped off. It was a few
hours before river ows could be passed again.
SWINGING BRIDGE DAM, US
The near failure of Swinging Bridge dam in New York state, US was
the result of a condition that had been recognised and understood.
However, the criticality of the condition was not recognised until a
sinkhole had formed at the dam. The damage that nally manifested
itself was the result of 75 years of accumulated distress.
There are number of other ageing dams in the US, many with a
history of problems. But when monitoring problematic dams, when
is enough enough? How does the team of owner, regulator, engineer,
and contractor determine when major and costly rehabilitations are
needed before failure occurs? And how do these decisions get made
without undertaking work that may not be needed?
A failure of Swinging Bridge dam would have major consequences.
A ood wave would incrementally increase the river level by 7.6m
before reaching the community of Port Jervis, 30km downstream.
The ood wave would travel over 241km downstream before its
effect was attenuated, resulting in cascading dam failures with major
consequences in the Delaware Valley.
Constructed from 1927-30 on the Mongaup river, Swinging Bridge
dam is an earth embankment, 304m long with a maximum height of
41m. There are two powerhouses with separate water conveyance
structures. An approximately 213m long, low-level conduit was con-
structed through the base of the embankment as part of the original
construction and is founded on glaciated alluvium.
A sinkhole was observed on 5 May 2005 along the upstream edge
of the crest of the dam, directly over the low-level conduit servicing
unit 1. Although reservoir levels had been within normal ranges in the
weeks preceding the sinkhole formation, the project had experienced
back-to-back ooding events in late March and early April, with the
record ood event at the site occurring on 3 April 2005.
Cracking of the crest access road extended approximately 27m east
and west of the sinkhole, indicating that the effect of the disturbance
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60 SEPTEMBER 2010 INTERNATIONAL WATER POWER & DAM CONSTRUCTION
RESEARCH
was distributed over a wide area.
Operations staff took immediate and appropriate action, including:
r Implementation of the emergency action plan, advising emergency
management agencies of a potentially hazardous situation.
r Opening the spillway gates and operating unit 2 at full capacity to
begin immediate drawdown of the reservoir.
r Shutting down unit 1 while leaving the penstock shutoff valve open
to prevent piping of soil into the penstock should a signicant crack
in the penstock exist.
Following these actions, it was determined that the dam, while sig-
nicantly distressed, was stable and the reservoir drawdown was
continued as quickly as possible. Remedial measures occurred in
mid-2007. The controlled relling of the reservoir was concluded
in late 2007.
Upon review it became apparent that the Swinging Bridge project
had a troubled past. No provisions for settlement of the conduit were
included in the original design. Settlement and cracking of the conduit
was observed during initial lling of the reservoir, along with silt
accumulation, although there was little reference to the volume of silt
that accumulated. Historical records are sparse between 1933 and the
early 1980s, though piping into the conduit was reported periodically
in the years between 1933 and 2005. Although it had slowed, settle-
ment of the conduit was still occurring.
The record ood event occurred on 3 April 3 2005 approxi-
mately one month before the sinkhole formation. The peak ood
stage was 0.8m above normal full and should have resulted in fail-
ure of the spillway ashboards. High tailwater in the at spillway
discharge channel prevented the ashboard failure. Although no
denite relation between the ood and the subsequent sinkhole
has been established, it seems an odd coincidence that the two
events were unrelated.
The high reservoir level may have reached a seepage path that
previously had not been exposed. It may have saturated crest soils
causing the soil bridging voids to collapse; or the sustained high tail-
water level resulting from continuous turbine operation may have
caused incremental settlement sufcient to open the penstock joints.
As piping into the tunnel started, the relationship between penstock
leakage, foundation piping, and settlement may have resulted in a
spiralling, accelerating failure mechanism.
Three piezometers had been identified as reading higher than
normal prior to the sinkhole formation. These piezometers, which
had a history of unreliability, were to be monitored in more detail.
However attention was diverted away as the ooding had caused
signicant damage that required action elsewhere.
A number of important lessons can be learned from the Swinging
Bridge project with respect to design, construction, monitoring and
rehabilitation:
r Avoid having conduits pass through embankment dams. If this
cannot be avoided, found the conduit on or within rock so that
settlement can be effectively eliminated.
r Install instrumentation that is appropriate for the potential failure
mode being monitored. Instrumentation must be trusted and behav-
iour that is out of character must be investigated immediately.
r Operations and maintenance personnel are the primary line of
defence with respect to dam safety. Functional exercises would
be very valuable in training personnel how to identify problems
and how to react.
r Potential failure mode analyses are an excellent tool to
identify problematic behaviour, and it is an appropriate way to
identify and prioritise remediation activities, while considering
risk and consequences.
This article was produced by IWP&DC in collaboration
with Chris Hayes, Director, Generation and Utilisation at
CEATI. The case studies used were reproduced with the
kind permission of CEATI International. The papers were
presented at the workshop Case Studies: Learning from
International Dam Incidents and Failures held in Los
Angeles, California, US on 24-25 March 2009.
Readers can obtain the full proceedings CD from http://
www.ceati.com/pricequote?publicationid=6057 or
publications@ceati.com.
References
1] A Dam Safety Incident Involving Erosion of Rock Joint Infill under a
Concrete Dam
Presented by: Mr. Peter Amos, Managing Director, Damwatch Services
Ltd., New Zealand
2] Lower San Fernando Dam
Presented by: Dr. I.M. Idriss, Consultant
Co-Author: Mr. David Gutierrez, Chief – Safety of Dams, California
Department of Water Resources
3] Failure of Belci Dam/Romania, Causes and Lessons Learned
Presented by: Dr. Alexius Vogel, Managing Director, Risk Assessment
International (RAI), Austria
4] Damages to Zipingpu CFRD Suffered During and 8.0 Earthquake
Presented by: Dr. Zeping Xu, China Institute of Water Resources and
Hydropower Research (IWHR), Chinese Committee on Large Dams
5] Sinkhole Formation Mechanism at Steinaker Dam: The Complete Story
Presented by: Mr. Karl Dise, Technical Specialist, U.S. Bureau of
Reclamation
6] Saluda Dam (Liquefaction Remediation)
Presented by: Mr. James Landreth, Vice President, Fossil and Hydro
Operations, South Carolina Electric and Gas Company
7] Lessons Learnt from an Earthquake related Internal Erosion Incident at
the Matahina Dam, New Zealand
Presented by: Mr. Murray Gillon, Chief Engineer, Damwatch Services Ltd.,
New Zealand
8] Sinkhole Remediation at Swinging Bridge Dam
Presented by: Mr. Adam Jones, Senior Engineer, Devine Tarbell & Associates
IWP& DC
CEATI Workshop 2011:
Case Studies: Reliability of Discharge Facilities
– Learning from International Incidents, Failures
and Best Practices.
CEATI International is undertaking a second case studies event focusing on
the reliability of discharge facilities. Scheduled for 15-16 March 2011 in Las
Vegas, Nevada, US. A Call for Presentations will be issued in early July 2010.
The workshop will be of value for all industry members including dam safety
managers and regulators; asset, plant and water managers; maintenance and
operations supervisors; systems planners and operators; mechanical, electrical
and civil engineers; consultants, manufacturers and suppliers. It will cover:
t Presentations of incidents, accidents, failures, necessary remediation
measures and best practices.
t Discussion of inspection types, frequencies and procedures.
t Recognising O&M and critical needs.
t Asset planning strategies and life cycle management techniques.
t Analyses and determining adequacy or structural and non-structural
solutions.
t Review of industry research and development efforts (past and current).
t Knowledge gaps – what are we not thinking about?
t Immediate and future needs to be discussed and identied.
For more details email: workshops@ceati.com or log onto www.ceati.com