>> Good afternoon and welcome to
the 18th annual Schnabel Engineering Lecture.
My role here is very brief.
I would like to welcome you here to
Virginia Tech and to welcome Alan Cadden.
Alan Cadden is the principal of Schnabel Engineering,
and a very good personal friend and
a very good friend of our program. Alan.
>> Thank you, Adrian. Good afternoon.
I'm happy to be able to introduce
the 18th Schnabel Engineering
Lecture here at Virginia Tech.
Especially at a time when
the civil engineering profession is exploding and
the infrastructure opportunities and environmental needs
will provide excitement and
many real challenges throughout your careers.
We couldn't present this lecture without the help of
Dr. Rodriguez and Mrs. Atwell,
as they do the hard work of making
all the arrangements here on campus.
We at Schnabel love this opportunity to
return to Virginia Tech each year and host this event,
so we thank you for welcoming us back.
Some of you may know this, but Schnabel is
approaching 70 years old or young,
depending on your perspective.
We have about 30 offices across the country,
and from these locations,
we offer services throughout
the United States and around the world.
We're excited to have announced that
JCK Underground joined
the Schnabel team at the beginning of the month,
which significantly increased the size of
our underground engineering and program management group.
We are a 100% employee-owned company at
the top and over our nearly 70 years of history.
We have grown in breadth of
services as well as geography.
Growing from
a traditional geotechnical engineering start,
to a much broader design firm,
now including full services around
specialty foundations, dams, and tunnels.
For me, some of the most exciting new work
involves applications of innovation around data science,
digital twins, and
advanced visualization within our workflows.
Given the challenges we face today
and the opportunities we see in the future,
we host this lecture each year
to bring you a different face of
our profession from outside the academic calls.
These lectures, many of them
recorded and available in your library,
present different aspects of
a career in civil engineering,
careers that have evolved over decades.
They share their stories,
they also do a little pontificating on
what you might see as your careers evolve.
Today we bring you a colleague and a friend of Schnabel.
Recently, I've had the pleasure to work
with Dave as a Deep Foundation Institute trustee.
So without further ado,
let me introduce our speaker for today.
David Paul, a Professional Engineer,
is the managing partner of
Paul Geotek Engineering LLC in Denver Colorado.
He retired from the Corps of Engineers after 22 years of
federal service as a dam safety officer
for the Mosul Dam Task Force,
which provided technical assistance
to the government of Iraq,
to mitigate dam safety issues
associated with the Mosul Dam.
A fascinating case history
itself for geotechnical engineers.
He also served as a special assistant for
dam safety at the Corps of
Engineers Headquarters in Washington,
DC, responsible for managing
the Corps portfolio of 715 dams.
He is a national specialist
on critical infrastructure design,
dam design, levee design,
construction engineering, engineering risk management,
interim risk reduction measures,
and dam and levee safety modifications.
He was a geotechnical subject matter expert for
the Orville Dam Risk Assessment in California,
which is the tallest earth dam in the United States.
He has been involved in the design and construction of
11 new dams and over 75
dam modifications around the world.
As I noted, Dave is currently a trustee
of the Deep Foundation Institute and a member
of the Association of State Dam Safety Officials
and the American Society of Civil Engineers.
In addition, as a member of
the United States Society on Dams,
he serves as the co-chairman of
the USSD Committee on Construction
and is active with the embankment dam committee.
He is also the USSP representative to
the International Commission on Large
Dams Cold Embankment Dam Committee.
Please join me in welcoming
David Paul to Virginia Tech, and Dave,
we look forward to your insights
on the history of dam and
levee safety in the United States. Thank you. Welcome.
>> Thank you, Alan,
for the kind words of introduction.
I am sincerely honored to be invited to come
today and enjoy the beautiful weather
on this beautiful campus here in Blacksburg,
and be able to come and speak to
you on behalf of Schnabel and Virginia Tech University.
Alan emphasized to me when he invited me
that he wasn't interested in a technical lecture.
I definitely took him at
his word and I assure you that the content
and my words today are
definitely not technically oriented.
But nonetheless, I hope that you find it
interesting for your career pass.
The presentation topics that I'm going to cover.
I'm going to talk about Fontenelle Dam,
which I don't think many of you have ever heard,
so precursor to Teton Dam.
And talk about the development of
dam and levee safety programs in
the United States and talk about how it
impacts infrastructure and as the profession
migrates towards risk-informed decision-making
in administering those programs.
I felt compelled I need to, I think,
give a bit of carbon dating for myself to you all.
As Alan said, my career has been federal.
Started with the Soil Conservation Service
in Illinois in 1976.
Went to Denver, Colorado to work with
the Bureau of Reclamation
after Teton Dam failure in 1978.
Worked there 32 years,
and then finished up eight years
with the Army Corps of Engineers,
as they stood up their risk management center.
When I started 78,
there were no cell phones,
there were no laptops,
there were no computers.
We had one rotary dial phone for
five people you could smoke at your desk.
All drawings were done by hand, on linen,
in a huge room there were 100 oak drafting tables,
filled with World War II Korean veterans who smoked,
and the work and the drawings that
they created were truly pieces of art.
But everything was done by hand.
All memos were written, long ham,
and taken to the steno pool,
and 25 ladies with typewriters typed out your memos.
That's carbon dating myself and we ran
stability analysis
from computer punch cards and took them
down to the computer room and slid
them through the window to run on the IBM.
Then an hour later, go back and hope that you had
some output and didn't have an incorrect card.
My point being, the amount of technology and
transformation that's happened in my professional career,
when I pause and reflect on it,
truly just blows me away.
You are all to me in this world
where technology is changing rapidly and frankly,
it's hard to keep up sometimes, but embrace it.
It's just unbelievable what you can do these days
with the power of computer and communications technology.
My professional career is rooted with the failure of
Teton Dam that failed June 5, 1976.
Teton River in Idaho,
designed, constructed by the Bureau of Reclamation.
>> As a result of this incident,
the organization underwent a very rigorous,
robust evaluation by independent expert engineers
brought to bear by the US government
to investigate the accident.
I have dear friends that were
involved with the design construction of Teton.
They were there throughout
construction and they're standing up by
the left abutment or the right abutment at
the spillway when the dam crest fell in.
They were there that morning,
started around 06:30 in the morning,
progressed quite rapidly to the failure at around 11 30.
Working for Reclamation in 77 and 78,
they hired about 500
of young engineers from around the country.
We repopulated the technical service center
in Denver and re-established the organization.
From that, they created
the actual dam safety office
within the Bureau of Reclamation.
I was asked in October 78,
45 years ago, by Richard Kramer,
who was running the organization
Embankment Dams Group at the time.
We're opening up the dam safety office.
Dave, we need some help.
Would you take some time and volunteer and help?
I said, "Sure".
I did so, and so I've been immersed with dam safety,
dam engineering, construction, my entire career.
It's again, fundamentally rooted in Teton Dam failure.
I had the great fortune to be blessed to
have many engagements with Doctor Peck over my career.
He served on several consulting boards for
dams that I designed and constructed.
This is his quote with respect to the failure at Teton.
Frankly, if you have interest in the damn levee world,
I submit reading those proceedings
from the investigation should be required [inaudible].
I'm sure you can find it online.
Again, I had good fortune
to talk to Doctor Peck
and others that were involved with the failure.
The state of the profession at
that time truly should have dealt
with the geologic conditions
that presented themselves at Teton.
There was truly a situation
where the organization failed, quite frankly.
Before Teton, there was actually Fontenelle Dam on
the Green River in Western Wyoming Earth Dam,
about 150 feet tall,
5,000 foot Crest Ling,
built in the '60s.
Frankly, instead of Teton Dam,
it could have been Fontenelle Dam in the '60s.
This is a picture of the foundation.
There were vertical open joints,
very problematic geologic conditions
upon which to build an embankment dam.
The design here you can see some of the open joints.
There was generally not
a rigorous clean-up program or treatment program and
the single line of defense to
mitigate foundation seepage was foundation grouting.
A fairly conservative section in
terms of the impervious barrier,
the impervious core,
constructed out of silt and gravity silt
similar to Teton.
Upon first filling,
you can see the amount of seepage that
manifested and reflected itself along the downstream toe.
It was not expected,
as you can probably appreciate.
But what really caused the incident or
the concern is this is May 1965.
The spillway is constructed over on the right abutment.
This is the spillway embankment contact.
Again, some of the pictures that I showed
showing the irregularities and
open joints in the foundation,
seepage migrated through, created erosion,
and there was a near failure here.
They were able to open the gates,
lower the reservoir,
and establish safe condition.
They then excavated this,
back filled it, reconstructed,
refilled the reservoir,
and lo and behold,
in July, a second event happened.
You can see the extent of it in the same general area.
Again, just a few months,
the same event happened again.
Emergency evacuation lowered the pool,
excavated this out, and rebuilt it.
Re-established the reservoir pool, and lo and behold,
there was a third incident that
occurred in September 1965,
much larger in extent.
When I see these pictures,
I'm constantly amazed that the crest didn't
fall in the damn breach causing release of reservoirs,
just a miracle that it didn't happen.
They excavated and rebuilt
this section and re-established the reservoir.
I point this out in that,
if you work for larger organizations,
you shouldn't be complacent.
You should guard against being complacent.
The Bureau of Reclamation,
they built Hoover Dam,
Glen Canyon, Grand Coulee Dam.
There was, in all honesty,
some arrogance within the organization,
having all of those grand dams in
their portfolio operating successfully around the west.
In response to this incident,
reclamation designers and
managers heard about Fontenelle,
but there was in talking to
engineers working in that era,
they heard about it,
but there was not widespread discussion,
presentation, or conversations about cause and extent.
This is truly before
a formal dam safety program was designed and implemented.
Moving on and again,
from Teton, 11 lives were lost.
The dam was essentially tapped
out and failed upon first filling.
In all honesty, if you go back to that era,
the state of the profession was mature and certainly
had the experience and the wherewithal to be able
to treat a difficult foundation.
This was volcanic assault,
lots of open joints.
But again, the organization
did not really heed the state of the practice,
and lo and behold,
the damn failed on first filling.
Again, some of the lessons learned.
The principal designer for the dam in
Denver visited the site one time during construction.
There was essentially little to
no coordination or communication
between the construction team
building the dam and the design team
that designed it in the Denver office.
There was no external review,
no consultant boards at that time.
Again, the primary defense
against seepage through foundation defects,
which were significant at this site,
was essentially relying on a single line grout.
Moving on to,
again the history as it relates to
dams as a significant piece
of our infrastructure in this country.
Where there's dams, there's dam failures.
I'll talk here in a minute about the NID,
the National Inventory of Dams.
In the United States of America,
there are 90,500 dams in the NID,
which I continue to find as
an astounding number of dams that have
been built and are registered in the NID,
which is administered by the Corps of Engineers.
Again, you can see with the NID,
the federal government, the Corps of Engineers,
Bureau of Reclamation,
TVA, has been able to keep track
of failures or incidents which
have generated these statistics.
There's low probability but nonetheless,
when you impound water and
create a lot of potential energy.
If you don't treat the foundation or design it properly,
certainly you can have a breach and release
a lot of energy. I apologize.
I know this is a bit of a hard slide to digest,
but it's a timeline and the intent here is to document
some significant failures in the United States.
There's Baldwin Hills, there's Fort Peck Dam slide,
Teton, Lower San Fernando.
There have been in our last 50-70 years,
some very significant dam incidents
or failures that have actually caused
the reservoir to be released and have
significant damages and loss of life downstream.
Certainly, the Teton Dam failure in
1976 generated the impetus within
congress and the federal agencies to generate
legislation and create a national dam safety program.
Again, another slide depicting.
Ironically at this time the
ICOLD and the Bureau TVA in the federal world,
they were self regulated dam owners.
They have their own portfolio dams.
The ICOLD has 715,
TVA has around 200,
the Bureau has around 400 dams.
When you compare those numbers,
sum them up and compare them to 90,500.
You can appreciate that it's maybe not a high percentage,
but nonetheless those agencies
have some very high and very significant dams.
Again, the turning point for
the dam safety program
within the United States certainly,
Teton was the impetus in '76,
and as a result,
the Dam safety Act was developed and passed.
Some other failure information to give you
some context of dam failures.
This record is 1848-2017.
You can see the number of dam failures is over 1,500.
All 50 states had a dam that failed.
The state with the most is Georgia.
Those states that had the
fewest were Hawaii and Louisiana.
Again, having this statistical information is quite
important in terms of developing the dam safety programs.
Some other statistics that came out from
Stanford University in 2018
are represented in this report.
Certainly would encourage you to reach
out and access that information.
Statistic that I find astounding is since
1980 so in the last 43 years,
there's been essentially 24 dam incidents per year.
That doesn't mean failure,
but there's been slides or there's been
stability issues that cause some emergency action.
It's essentially a two a month for the last 33 years,
which again, I find to be rather astounding.
As I said, the National Inventory of Dams was created,
mandated by Congress as part
of the Dam Safety Legislation.
This is the URL for that.
The ICOLD maintains this database.
It interacts with each of the 50 states.
Each of the 50 states does
have a legislated active dam safety program now,
Alabama was the last,
but last year, or maybe the year before,
they did finally pass legislation and
fund and started Dam Safety Programs.
That conglomeration of all 50 states,
resides under the Association for Dam Safety Officials,
ASDSO.
The other organization primarily focused on
dams in the US is the United States Society on Dams,
USSD, which is again affiliated with ICOLD,
which is the International Commission on Large Dams.
Both USSD and ASDSO meet annually and as Alan mentioned,
certainly would encourage as you
move into practice or proceed in your career.
You certainly should reach out
and engage with those organizations.
Some statistics from NID.
It's used by the National Dam Safety Review Board and
Association of State Dam Safety Officials
to inform legislatures in their states,
to inform Congress and federal agencies
to recommend dam safety policies.
Many of those changes reside in WARDA legislation,
Water Resources Development Act.
They're not passed every year,
but every couple of years WARDA passes through
Congress changing policies or adding new policies.
More than 65% of the dams
in the NID are classified as low hazard,
50% of them are less than 25 feet in height,
and almost as I said,
70% of the dams are privately owned.
Again, the privately owned dams are regulated
by the state dams safety programs.
The average age of the dams are 60 plus years.
With respect to levees,
this is a map from ASCE and FEMA showing the counties,
dark green, that have levees.
There's 150,000 plus miles of levees in this country,
and there's about three million miles
of river in the United States,
which again, I find this an astounding number.
But again, there's 150,000 miles of levees.
The Corps of Engineers is
the principal federal agency associated with levees.
They designed and are responsible
for 15,000 miles of levees,
so they're about 10%.
Those that may have grew up or lived around some
of the major rivers like the Mississippi, Missouri,
Ohio, all can probably remember
significant flood hydrologic events
in your lifetime that caused flooding.
These are just some numbers and as you can see,
these damages are significant.
They're not a couple million dollars,
this are multiple billions of dollars from these events.
The last 2017 was over
$125 billion in damages from extreme hydrologic events.
This is an interesting figure.
Again, somewhat difficult to see, but in 1927,
the flood on the Mississippi generally is the event that
created legislation and led to
the Levee Construction Program in the United States.
Again, there's levees
both sides of the Mississippi
from Minnesota clear to the gulf.
You can see it's constrained
the river and allowed it to be operated in
a very efficient manner and certainly has
reduced and eliminated a lot of
damages that could have been caused from flooding.
You can just see between 27 and
2011 there were over almost 17 million acres
affected by flooding in 27 and
somewhere over six million in 2011 floods.
The amount of damages that were mitigated or
eliminated by the levees are again very significant.
Congress passed National Levee Safety Act in
2007 as part of Water Legislation 2014.
The Corps of Engineers is taking the lead to
implement the National Levee Safety Program.
Again, Corp is responsible for 15,000 miles of
levees and they are working with each of the 50 states.
The goal is to bolt onto
the existing dam safety programs within the states,
a levee safety program.
Similar to NID,
the Corps has created the National Levee Database.
In the last decade,
they have been able to assess and populate
the levee database for the 15,000 miles of
levees in the country that the Corps is responsible for.
They're working again with states and
other private owners to assess
their systems and to
get that information into the database.
As I know you all can appreciate is having
this historical information is
the foundation for any safety program.
Certainly, is quite important
as the organizations continue to assess
the performance of their structures and make
decisions as to whether they're
safe or unsafe and if they're unsafe,
what actions are required to
bring them to acceptable levels of failure,
as I'll get into here in a minute.
Again, the levee database is
summarizing periodic inspections, special inspections.
It also includes failure modes,
which I'll get into here in a minute,
and the general health, if you will,
of the levees as part of being able to assess
them and be able to take corrective actions when needed.
Again, I find some of these statistics fascinating
in that 75% of the US population was born after 1960.
I've said it to Alan over breakfast this morning,
I'm so impressed with the vision of our forefathers,
those that came before us in the '30s, '40s, '50s,
their vision to create
the infrastructure throughout the United States,
the water infrastructure of locks and dams and harbors,
ports, levees, hydropower,
they truly had a vision for
advancing the standard of living in this country.
Being able to increase commerce of
Ag products from the agricultural areas of the country,
through the rivers, to the ports.
I say this because I say our generation,
I'm not sure we've been as visionary as our forefathers.
We should all I think
give them the credit where credit is due.
I think you,
the younger generation,
coming out of universities such as Virginia Tech as you
go forward into practice and working on various projects,
you're the next generation that
can make a difference, if you will,
into keeping our infrastructure
operating and at a high level of safety.
Again, I find those statistics
rather fascinating but again,
try to give credit to the previous generations.
Transitioning from the traditional view
of infrastructure of safety
was generally fundamental engineering strengths
of materials,
geologic characterization, laboratory testing to
identify engineering properties of
materials and from there,
utilize existing materials to design dams or levees,
and construct them with stable slopes
and such that they could handle
the hydrologic and seismic loads
without failure and this were,
and still are standards-based.
You're certainly experiencing all of those factors,
all of those areas as you continue and
progress through your education.
But in the last 30 years,
at least in the federal world,
and it's slowly transitioning from federal
to states and other private owners,
we're transitioning to get to
a risk-informed view of the infrastructure.
In that context, you'll hear
the word risk almost
universally in just about every sentence.
Fundamentally, it's a function of the hazard,
the loading response to that loading,
and evaluating the consequences.
As I said in the early days of dam safety,
when I was working at the Bureau of Rec,
we, I think, did a good job
of evaluating the potential failure modes.
We might not have used that particular term,
but we certainly identified the geologic conditions,
evaluated strengths of materials,
and decided whether we needed a cutoff wall,
or whether we needed to grout the foundation or do
some other special means of foundation treatment.
We stood on the crest of the dam and said,
well, there's a lot of people down there,
but we didn't really exert the analysis to
categorize and assimilate that information
as it was part of our decision-making,
it was not really a formal part of that.
Again, as we transferred,
if you will, into
those risk-informed decision-making process,
which is the guiding principles for
our safety programs, again,
we spent a lot of time and
rigor to evaluate the loading conditions,
assessed how the dam or levee would
perform under those loading conditions, and certainly,
we've put a lot more rigor in
assessing the potential consequences.
It certainly has been well served
in coordinating in the federal community of dam owners.
But it's also been very powerful in communicating
with our legislatures in each state,
as well as Congress in terms of
defining the condition of our infrastructure.
As I said, average age of dams is 65 plus years.
There's over 600,000 bridges in the United States,
150,000 miles of levees,
untold numbers of roads and pavement, and that thing.
Again, the extent of
our infrastructure that we all benefit
from is truly amazing when you consider it.
Truly, most of it has been built in
the last 100 years of our country.
Being able to articulate
to the legislatures and to Congress
about our needs as agencies like the Core, Bureau, TVA.
We have this infrastructure.
It's in this condition.
We need these monies
appropriated so that we can go forth and
execute modifications or repairs to
these structures to maintain their serviceability.
Again, a very interesting graph here.
This is a chart over
the last 120 years from 1,900 present,
showing the number of
dams constructed in the United States.
You can see after World War II, '30s, '40s, '50s,
just a tremendous amount of dams that were designed and
constructed in the United States by the Bureau,
core, TVA, other agencies and organizations.
Since the '80s dam construction with
the implementation of environmental regulations.
Certainly, it's more challenging to move forward
and modify structures, giving those regulations.
I've had the great fortune worked on the last two dam,
major dams built in the United States.
Ridges Base and dam for
the bureau outside of Durango, Colorado,
and the core constructed Portuguese dam,
RCC Dam outside of Ponce, Puerto Rico.
Again, I've been blessed in
that I've been able to work on
a significant number of
dams around the country and around the world.
I've been able to also modify and work on several.
Again, having ended my career with the core,
I have quite a few statistics
primarily focused on the core.
Again, the core in their portfolio has 715 dams,
almost 90% 86% are embankment dams.
The average height around 93 feet, and again,
average age 65 years or so.
This is just a map of the United States showing where
the major dams are located within the core inventory.
Again, the core has 715, the bureau,
around 400 TVA around 200.
Burke regulates 2,200 dams or so,
and then NRCS has approximately
22,000 dams in their inventory.
Over the last decade as the cores transitioned
from two risk-informed decision-making,
they have assessed each of their structures.
You'll see this chart,
this is FM chart.
The X is annual probability of failure versus life loss.
Dots that plot above the line
are pieces of infrastructure dams,
levees, locks that have high risk.
They've been assessed.
Failure modes have been developed,
and evaluated and judged by
a multi-disciplinary engineering team
that the dam needs to be
modified or the levee needs to be
modified to obtain or maintain safe operation.
Almost half of the 3,000 pieces of infrastructure
that the core maintains and
operates on behalf of the country,
about half of that inventory needs
is judged to be high risk and needs to be modified.
In addition to dams and levees,
the core operates about 240 lock structures
on the major river systems in the country,
again representing a value of $3 trillion.
Again, a tremendous portfolio of infrastructure.
As the core has transitioned,
they would tell you that it's not
necessarily the structure of 65 years old it's
because the major risk drivers that have been
identified is just there were
defects or flaws in the design.
The state of practice,
material technologies have changed.
Concrete is iron-trained now,
with many additives so the durability of concrete
is much better than it was say back in the '20s or '30s,
those kinds of things.
But as you can appreciate,
the country's population has increased
dramatically in the last 100 years.
Last census, we're somewhere around 330 million people
in this country so
the amount of consequences
the property development houses,
people living behind dams or
levees has grown exponentially,
thereby creating the risk.
Fundamentally risk inform methodology
allows organizations such as the bureau
or the Core to be able to rack and stack.
If you own 3,000 pieces of infrastructure,
how do you decide what to work on first?
Risk has been very powerful in being able to assimilate,
evaluate the portfolio of infrastructure,
and be able to decide this is Number 1 priority,
and this is Number 3,000 priority.
Again, it's very powerful in working,
coordinating with legislatures and Congress,
to be able to tell that story in
a compelling and persuasive manner such that you
can solicit and obtain the funding
so you can go forth and maintain these structures.
Again, the Core has
spent a considerable amount of effort,
money, and labor hours,
to develop databases and be able to continue
to track the condition of the infrastructure.
As I said, having these statistics, this information,
we've been able to tell
a very powerful and compelling message
to the legislature.
This is just a general graph,
if you will, or chart,
being able to identify and depict and show
a particular failure mode and is
it a high likelihood and what's the consequences.
Of course, red being more critical than green.
But again, this, you might all
view it as rather straightforward and commonsensical.
But nonetheless, it still
becomes a powerful tool to be able to
communicate this in terms of what do you know,
what do you not know, what truly?
Try to be able to
assimilate information and be able to tell that story.
You're able to tell where the source of risk is.
Then through engineering, you're able to be able to
identify those engineering solutions
that you're asking money for to go forth,
so fundamental to any of
the dam safety levee safety programs
ongoing in the country.
Life safety is paramount.
You'll hear it, and it may sound cliche,
but nonetheless, it's truly the guiding principle.
Life safety is the critical aspect of
decision maker sitting at a table
evaluating information and trying to make decision.
Again, somewhat cliche, but we say it all the time in
our meetings and as we evaluate
structures and try to make decisions, we do no harm.
If we need to modify the structure.
The principle is do no harm let's modify it,
but let's not increase the risk during
the construction period to unacceptable levels.
I think one of the great things
with the transitioning to risk
informed is we're now starting to
really focus on systems approach.
We're thinking of the Mississippi River or
the Ohio River as its own system.
We're not just focused on lock and
dam 26 outside of St. Louis we're
truly looking at the river as
a system similar with like
the Missouri River that has
some very significant dams, Fort Peck.
These are some of the largest Earth
dams the world on the Missouri River.
When we go through and evaluate them,
we're truly looking at it as a system and
looking at the potential for cascading failures.
If say, Fort Peck
released its tremendous volume downstream,
how would that impact the lower dams?
Very powerful. It's very periodic and continuing,
so the regulations policy
that's been developed every 10 years.
Every 10 years, a dam or a levee goes through
a very rigorous inspection by
a very experienced, multi-disciplined team.
That information again, is evaluated.
Failure modes are reevaluated,
and those that rise to the top as
the highest risk are those that are worked on.
Some of the lessons learned as
we've transitioned over the last decade
is many would view
standards-based approach as inadequate.
Problems typically have been
shown to be larger than we expected.
Again, over half of the pieces of
inventory that the core manager
has judged to be in need of repair.
Again, given their age,
that really probably isn't a surprise.
But again, being able to evaluate them,
assimilate them, be able to figure out whether
it's a concrete deterioration problem,
or the valves need to be replaced,
or the gates need to be upgraded again
are all very important as we move forward.
Certainly it's not always intuitive what's risky,
and we have to keep reminding ourselves,
certainly it's a marathon and not a sprint.
We've been able to become much more
intelligent about the status
of our infrastructure in this country,
dams, bridges, levees, those things.
I think those of us in
the federal agencies being responsible for the portfolio,
we definitely go to sleep at night believing
that we're taking care of
the taxpayers money in
a very responsible manner and
definitely serving the citizens of the United States.
Moving on to some of
the concepts and practice of risk assessment.
It started back in the '80s.
You can see this chart here where dams fall.
Generally all areas were evaluated,
chemical engineering, railroads, those things.
You can see consequence of failure.
Probability of failure was generally 10^-4.
One in 10,000 is
generally the average probability of something
failing like a dam or levee.
Again, started in earnest in the '80s,
certainly with NASA,
the space program, and the development of
rocket travel and all of
the engineering that goes associated with that in
terms of failure modes certainly
brought that forward as
far of other civil infrastructure.
Again, 1979 Federal Guidelines in 1983,
Research Council was the pioneering aspect
for the federal agencies.
In this Dam Safety Act of '78, '79,
there was specific language written
that focused the agencies to start
thinking in terms of risk and failure modes.
Again, a lot of this has its root
in the space world NASA.
As you can see other countries,
in Britain, Hong Kong,
and in particular in Australia,
those countries also began developing
the methodologies and the processes
that we continue to utilize.
In late '70s transitioning through the '80s and the '90s,
reclamation probably led other federal agencies
in developing risk informed decision making.
The first study was done for Jackson Lake Dam
in 1976 and was led by Larry Von Thun,
who really pioneered the development
of risk analysis along with Dr. John Smart at the bureau.
There was a team formed and they developed
the first guidelines, if you will.
Larry worked with the Canadian hydros,
BC Hydro in particular,
and began developing the processes where
we evaluated the structures, developed failure modes,
and went through a methodology to evaluate,
could a dam fail and start assessing
probabilities of a potential failure mode.
Parallel to that, we also put
a lot of rigor into upgrading and
reevaluating the hydrologic floods
and the seismic earthquake loadings
and certainly then there was a lot more rigor
put into evaluating consequences.
The bureau has been through their inventory of
400 structures in the last 40 years.
They've been through it 4-5 times.
Essentially, they have fixed
their highest risk structures in those 40 years,
but they continue to monitor them through
the instrumentation and through
their inspection program,
and continually re-evaluate failure modes
and re-evaluate the loading conditions and
consequences and continually updating
the risk assessment if you will or the risk category.
Again moving forward, trying to apply to the timeline.
You're transitioning from '70s
through the '80s to the current.
Now, if you're involved in the business,
certainly the states are becoming very active.
Trying to move forward.
I think I'm pressed for time a bit.
Again, a busy slide, so I apologize.
But again, trying to summarize
the various milestones along the time lines.
Trying to move forward a bit.
To give you a bit of context,
what is damn safety risks?
It's simply the probability of
some undesirable event occurring that would
generate serious economic consequences
or life loss downstream.
I said we wouldn't have formulas,
but here's the risk formula,
which is again the probabilities of the loading.
Evaluating the probability of
the response of the structure to
the loading by the consequences.
As I said, considerable amount
of energy within the federal world
and in academia around the country
to evaluate the loading conditions.
I know those of you in hydraulic engineering, certainly,
considerable amount of effort
ongoing at this university with
seismic research and seismic evaluations,
trying to do better,
and get more educated
on what those loads are and how structures would respond.
Again, this is a typical event tree.
Typically there's eight nodes,
if you will, to a typical event tree.
Is there a flaw and what is the loading?
Then stepping through whether that would
create a failure of
the structure and release of the reservoir.
Several software programs have been developed.
LifeSym and others, continually
being developed and upgraded to
evaluate the consequences and with
today's GIS technology being able to
truly look at limits of inundation from breach,
and quickly assessing population
at risk and assessing potential life loss.
Again, the rigor and the ability with
today's technology to do that is just amazing.
With that there's always uncertainty,
so we're definitely always trying to
assess if we make a risk evaluation how certain are we,
what are the bands of uncertainty and
certainly factor that into decision making.
There's aleatoric or statistical uncertainty.
An example, might be statistical variation in
a filter boundary that you
can evaluate from controlled laboratory test.
Epistemic uncertainty is,
if you didn't know about it,
that creates its own level of uncertainty,
so those things are included in a risk assessment.
There has been numerous guidelines developed.
The federal guidelines for dam safety
was put out in '79 as part of the legislation.
The bureau's first risk protection guidelines
came out in '97.
Core published their dam safety guidelines in 2011,
and then all the federal agencies put
out the federal guidelines in '15.
Most recently fur
the Federal Energy Regulatory Commission has issued
their own risk guidelines which are
similar to the core and to the bureau's.
Again, they regulate about 2,200 dams in the country.
As you can appreciate,
there's various levels of
risk analysis from a screening level to a moderate,
to a very though and complex depending
on what decision you need to make.
Certainly the more rigor that goes into
it with more information allows for
a robust evaluation and very solid information
for decision makers to make in terms
of figuring out what
structure needs to be worked on first.
Again, this summarizes those four levels.
Level 1 being the simplest,
the screening risk analysis,
Level 4 being the most rigorous.
Sometimes like for Oroville
after the spillway event there.
To evaluate that structure to a Level 4 screening took
several million dollars and took
about six months of about 30 people working on it,
so it's not a trivial level
of effort or trivial amount of money.
When you talk about doing
a very detailed risk analysis
for complex structures like Oroville.
The Core and the Bureau of collaborated and
developed the best practices training course.
It's 40 hours,
given at various locations around the country,
transitioning that to USSD to be able to
broaden the exposure of that training to the
profession. This is from FERC,
this is the different levels
of failure categories that you might use as
a guide when you're making your evaluations.
These are, again, several categories that are used
in assessing life safety as well as those economics.
Again, screening level is the simplest,
may take a day,
may take several days.
A moderate one might take 40 hours and something
like a Level 4 may take
several months and several million dollars.
Again, it allows in
combination with standard based typical factors
of safety and strength of materials,
we're able to bring into play the failure modes.
Are they risky, are the loading conditions correct?
Be able to make
a better informed decision on behalf of the taxpayers and
the citizens of the country to be able to invest
our tax dollars in
the most effective and efficient manner.
Comparing standard based to
RIDM if you can read the table there,
so standard base with
definitely more focused on the loading,
reaction, strength of materials,
stability, those evaluations.
Same applies under RIDM,
but we're looking at a wider range of
loadings and we truly do assess and try to
put probabilities to those events
in order to be able to rack and
stack and to be able to determine
which has the highest risk and
which should be worked on first.
Again, these are all the components
associated with utilizing RIDM.
Over the last 20 plus years where it's been used in a
detailed and part of
the organization's operation of their infrastructure.
It's definitely improved our understanding
of that structure and the pieces of it
and be able to bank better in decisions financially
and from an engineering perspective.
This again summarize the elements
of dam safety risk management.
You have the risk assessment,
and then trying to make decisions,
typically displayed in an FN chart.
Again, probability of failure versus loss of life,
and the line there is those summary probabilities.
The plot above result in action.
There higher risk and those below would be lower.
The goal is with
the expenditure of money and implementing
engineering solutions would be to reduce that risk and
get your failure modes to below the line.
You'll hear that term quite frequently.
Just some final thoughts.
Unfortunately, I think in our country,
particularly in my lifetime professional career,
we seem to struggle as a country
to develop a long term vision,
if you will, or long term policy.
Unfortunately react to catastrophic events.
Key term is catastrophic event
that resulted in the dam safety legislation,
which forced federal agencies to start taking
a more robust evaluation of their infrastructure.
Katrina cause the Corps to look at levees
and to look at flood walls and coastal protection.
Unfortunately, I think we
react to catastrophic events
as a country and as a nation.
I think as you go forward in your continued education,
as you move into the workforce
and become part of our profession,
hopefully you'll leave a lasting impression and be able
to advance policy and be able to
advance our profession to a point where we do
less reaction and maybe
look forward and try to do more planning.
Again, tremendous amount of damage
is done by hurricanes or by dam failures, levee failures.
We all need to be cognizant of
that as we continue our education, and again,
move in and be able to help everybody associated
with maintaining what we
have built and our forefathers had built.
Some summary statistics of
civil works value to the nation.
I've again impressed for
$1 that spent by the government on
flood risk management prevented
over $8 return in flood damages reduction of that.
Again, our forefathers over the last 100 years,
this country has built some of
the world's most robust complicated infrastructure
that we've all benefited
from and certainly as you go forward,
I think you all have that responsibility,
if you will to take that on in maintaining that.
Again, ASCE puts out their report card,
as you can see, for 2021 for
the various categories we're not doing the greatest.
Again, as Alan said at the beginning,
become involved in these professional societies.
In these organizations, we
are the profession's mouthpiece to
our legislatures and to our Congress
in order to increase our funding,
to be able to make infrastructure a priority.
This administration has been able
to pass the infrastructure bill,
which has secured funding,
and it's certainly a step in the right direction.
But as you can see by our report card,
we still have a long ways to go
to get up to acceptable marks I think.
Lastly, again, I had the good fortune in
my career to be associated with some phenomenal people.
This is a picture of Dr. Don Deer, Dr.
Skip Hendren, Ralph Peck, and Spike Underwood,
who was the Corps of Engineers chief
geologist at headquarters for about 20 years.
They were the consulting board for New Adel Dam,
which I was responsible for outside of Phoenix.
I was telling Alan again at breakfast,
just tremendous memories of
the impact that those gentlemen had
on myself as a person and certainly
on my professional career going forward.
Best of luck to you in
your education and your professional career.
I wish you the best.
Again, thank you for your courtesy
and for your taking time
out of your busy lives to come
and listen to me ramble, so I appreciate you.