On the Front Lines of Dam Safety

Each of the 90,000 dams in the U.S. plays a critical role in the community it serves — from preventing floods, to generating hydroelectric power, to providing a water supply for drinking water, irrigation and recreation. On this podcast, meet the professional rope access technicians whose jobs involve preserving the structural integrity of each dam — by providing a rarely seen perspective of some of the largest infrastructure in the world. Collectively, our team of more than 40 certified by the Society of Professional Rope Access Technicians has logged approximately 50,000 hours suspended from ropes, getting an up-close view of dams, bridges, tunnels and other hydraulic infrastructure.

Episode Transcript

(00:03):
I'm John Torek. And I'm Danny Sullivan. And
you're listening to Speaking of Design. Bringing you
the stories of the engineers and architects who
are transforming
the world one project at a time. Help
Wanted.
Seeking a thrill seeking applicant with specialized training
who wants to protect thousands of lives. Today,
we'll meet professional rope access technicians whose jobs

(00:25):
put them on the front lines of infrastructure
safety every day.
So we find ourselves on the top of
a dam, and sometimes we gotta make our
way down through the gates. You have to
step over the railing
and lower yourself onto the rope and the
harness. That's Mike Fuga, a senior geologist in

(00:48):
HDR's Berkeley office and a member of the
rope access inspection team. And for some reason,
that just doesn't seem natural in my head.
So that first step is a doozy, trying
to get over the railing there, and my
heart's usually pumping. His colleague, Kenny Desange, knows
that feeling. When you're going over the railing,
you're not really taught on your rope yet.

(01:08):
You have to sit into it. And so
just that feeling of I need to lean
over this this hundred foot drop and sit
into my rope
definitely had me what I call depth gripping
the handrail to make sure when I sit
into this, I'm not going anywhere.
Kenny lives in Sacramento
and is the hydraulic structures practice lead for
the company. He and Mike are among 44

(01:32):
inspectors and technicians at HDR,
certified by the Society of Professional Rope Access
Technicians
or SPRAT.
Collectively, the team has logged approximately
fifty thousand hours suspended from ropes, getting an
up close view of dams, bridges, tunnels, and
other hydraulic infrastructure.
Those hands on inspections

(01:53):
have given team members a rarely seen perspective
of some of the largest infrastructure in the
world, including California's Oroville Dam, the iconic Golden
Gate Bridge, New York's Bayonne Bridge, and Idaho's
Dvorak Dam, the third largest dam in The
US. Like Kenny and Mike, most inspectors enter
this career of adventure without any rope experience

(02:16):
with merely a degree in civil engineering or
geology as the first qualification.
But occasionally,
someone enters the field with more of a
thrill seeking background.
Growing up near Yosemite, doing a little bit
of rock climbing was sort of like a
prerequisite. I wanted to graduate eighth grade, I
think. And then going to HDR, I didn't
know I would be involved in the rope

(02:37):
access program. That's Travis Ford, a hydraulic structures
lead based in Denver.
He began his career with more typical structural
engineering work, which led to the opportunity to
join the rope access inspection team. Whether it
was spillways and, you know, big infrastructure or
fish ladders, it sounded pretty neat for a
young structural engineer. So I I did that

(02:57):
and joined and started working on some levee
projects and some hydraulic structures, and then sort
of started following Kenny around on inspections
and showed interest in that. In spite of
his rock climbing background, Travis still remembers the
intensity
of one of his first dam inspections. I
went straight to Detroit Dam in Oregon,

(03:17):
and that one happens to be about 470
feet high. And the access to it, we
had to climb up over the skin plate
of this big hydraulic gate. So we had
to climb, like, under the bridge and over
the skin plate and then get over the
top, and and there's no, like, foothold. But
you go over this edge,
and we put little rope protection on and
set the rope over the top. But I

(03:38):
did a little peek with my hands over
the top of the gate and looked down,
and and I'm like, okay. And so everything
just got very methodical.
It was a similar career path for Jarlene
Nineveh,
a structural EIT who works with Travis.
She moved to Denver after graduating from the
University of Buffalo in 02/2018.
I actually didn't know anything about the rope

(03:59):
access industry prior to HDR.
And working under Travis, I think the first
time we did a few
seat out inspections, and then I've seen the
monrope. And then we all went to a
warehouse
where we kind of got to practice, and
that's where I got introduced to the rope
access. And it looked like cool thing to
do. Getting out of the office, seeing breathtaking

(04:20):
views,
actually experiencing
the structures you study on screen. If you
have the stomach for hanging 500 feet in
the air with the wind whipping in your
face, There's a lot to like about a
career in rope access inspection,
although that doesn't mean your family and friends
will agree. And
and all my friends don't understand why I
do it.

(04:41):
But I always explain the same thing, you
know, the two system robot. I don't think
my mom hears any of that. She just
sees these pictures that I showed her, and
she doesn't like it at all. My mom
still does the same thing, so it doesn't
it never goes away.
My dad won't go out there. Like, he's
had the opportunity to go, you know, that
we had a dam right near where I
grew up, and he just stayed at the

(05:01):
abutment. He won't go out there. If you're
listening, mom and dad, there's a lot of
training required before any team member ever steps
into a harness.
On this port set here,
which is the same line that I'm ascending
up.
My backup is on So there's three different
certification levels,

(05:22):
one, two, and three.
And really at the one, that's essentially a
worker level. So you're going in without any
any type of rope access experience.
You learn various maneuvers to make sure you're
comfortable on rope along with a couple of
rescue
sprat certified level one technicians,

(05:43):
meaning they've completed that first training course. It's
four days, and then the fifth day is
kind of the the written test
and the oral test, and then
all the maneuvers you have to go through
to get the certification.
So it's basically going through
all of the basic things like
ascending, descending,
knowing all of your gear, a few of

(06:05):
the maneuvers like rope to rope transfers and
stuff like that, and then you have to
show all of that you learned on the
last day. Kenny's now a level three, but
he also came in with no experience. Honestly,
I had zero background with any type of
rock climbing or rope climbing or anything like
that. I just remembered day one at the
training center

(06:26):
trying to put on the harness, and I
was like a tangled mess, essentially. So I
really didn't have a lot of experience going
into it. After you pass level one and
reach five hundred hours of experience,
you can pursue level two certification. Once again,
you go in. It's another four day course
where you're learning more advanced
maneuvers and also really focusing on rescue techniques

(06:46):
there. Travis and Kenny have reached level three,
which requires more than 1,000
on the ropes.
Similarly, level three certification
involves a four day training with a fifth
day of written tests and independent reviews of
your maneuvers. The level three duties are to
be the supervisors of the job to be
able to supervise multiple people underneath you who

(07:07):
are working on that job and also confidently
put together job hazard analysis,
safety plans, inspection procedures.
So you're you are in charge of that
job, so making sure you're comfortable with those
duties. For Mike, the biggest takeaway was simply
to always be mindful of safety once you're
in the air. So in terms of safety,
you know, it's really taken the time to

(07:28):
think about what you're doing because you do
have to transfer between ropes. You've got your
gear and everything. And so it's just been
real mindful of yourself, your surroundings,
and what you're doing with the ropes just
to make sure you don't find yourself on
one point or on no points, especially since
you're suspended up to the air. And
sometimes it's six feet off the ground, sometimes

(07:48):
it's a few hundred. And even with no
prior experience,
that preparation calmed his nerves for his first
inspection.
I got this weird thing where if there's,
like, a system in place,
I like, my fear gauge. I I have,
like, a switch. I can kinda, like, turn
off fear almost.
So shark cages are an example. The system
here, right, you got, like, a two rope
system. So it's like, alright. We got our

(08:10):
main line and our backup. So
as long as I don't do anything stupid,
everything should be just fine. Even if something
does go wrong in the air, Kenny explained
that the redundant rope system provides extra security.
So let's just say someone was to freak
out and just kinda lose it on rope.
If they just let go of everything, they're
actually just gonna stay in place. It's not

(08:31):
like they're going to to drop down to
the end of the line or anything like
that. And so it's a even if you
load items up backwards or put it on
the rope backwards,
you'll just stay in place. And so it's
a really good feature of our equipment to
where
if you were if something was to go
wrong with either user error or even a
functionality,

(08:52):
you'll just end up staying in place and
not going anywhere. It's not like you're gonna
go down the road. The training helps each
team member become familiar with the long list
of equipment needed for an inspection.
So, basically, we plan out how much rope
we're gonna take out into the field, The
stuff we're gonna use for anchors, so it
could be wire sling,
soft sling. We have Ropel, which basically protects

(09:14):
all the soft goods or soft materials.
We have carabiners
that blocks everything and helps build the anchors.
Then on top of your personal protective equipment
like your helmet, boots, and gloves,
as well as rescue kits and first aid
kits, you still have the tools needed for
the job. Those include rock hammers,
clamps, calipers, headlamps, cameras, iPads,

(09:36):
batteries,
special rain paper notebooks that can be used
when they're damp, and Motorola radios with a
specific FCC approved channel for communication.
That's a lot to hang on to while
you're suspended from a rope. We never drop
anything. That I don't think I've ever seen
that happen before. So, you know, it's it's
definitely %. One hundred % tie off. Right?

(10:07):
I'm being totally sarcastic when I say we
don't drop anything. We we drop things all
the time. I think the high value ones
were I think someone dropped their car keys
or a rental car key before.
I I've dropped my notes. I've been lucky
enough to where they floated on top of
the water, so I've been able to get
them in. But, you know, radios, I know
a camera went in in Alaska. And when
that happens, it doesn't get ignored by the

(10:28):
team. Yeah. Not we have a yearly award
for who drops the most expensive item, and,
you know, we're trying not to get on
that list, but it's it's pretty funny to
bring it up. With nearly three thousand hours
of experience on the ropes, Travis has two
such awards to his name. The first involved
a friction device called a GriGri that helps
you descend in a controlled manner.

(10:48):
However, when you change ropes, you have to
detach it. I decided to just take mine
and and set it nicely on the spillway
slab, but, you know, I'm I'm secured, but
the the spillway is actually at an angle.
So I think Kenny describes it. He just
said, Travis, just set it down and and
just watched it roll down the spillway.
So, anyway, that's that's that's the first one.
Travis received his second award shortly after he

(11:11):
got a new TUF phone. And they were,
like, you know, the newest, coolest TUF phones.
So I decided to keep that in my
pocket. And, you know, the harness tends to
work its way a little bit, so I
was climbing up. I don't know. But it
slipped out of my pocket, and it landed.
It went down about
70 feet or so, hit the top strut
of a radio gate, blew apart. You know?
It was it was only so tough.

(11:31):
And then it rolled down into the Stilling
Basin, and, of course, we couldn't go down
there because they were they're spilling from the
powerhouse or something. So, anyway, we we tried
to call it and look at that. I
swore it lit up in the Stilling Basin
for a split second and rang. Although the
team has a sense of humor, they take
their safety seriously. Rope access is a two
rope system. I carry that through a lot
of my gear, actually. I actually have a

(11:53):
backup line on my camera in case, you
know, that were to go sailing. We have
tied off, in my case, maybe twice, heavy
tools, hammers, things like that. When we're over
any kind of, like, public traffic, that kind
of thing, we'll close that area,
typically, just in the case that something were
to fall or somebody drops a water bottle
or debris from the structure, that kind of

(12:13):
thing. So, yeah, on the safety side, we're
well aware of the the hazards there and
and mitigate that.
In addition to Sprat technicians who inspect bridges
and tunnels, the team has experience analyzing, designing,

(12:33):
and inspecting
all kinds of hydraulic structures.
This includes concrete dams, arch dams, spillways,
hydraulic gates of all kinds,
canals,
penstocks,
energy dissipation structures, walls, platforms at hydraulic projects,
and intake and outlet works.
Each of the 90,000 dams in The US

(12:56):
plays a critical role in the community it
serves,
from preventing floods to generating hydroelectric
power
to providing a water supply for drinking water,
irrigation, and recreation.
That's why the rope access team plays such
a critical role, giving dam owners the detailed
information needed for third party inspections,

(13:17):
stability analysis,
security analysis,
design modifications,
regulatory compliance,
construction reports, and long term planning.
It's all about dam safety through routine surveillance,
monitoring, and maintenance
to preserve the structural integrity of each dam.
The work begins long before anyone is strapped

(13:37):
into a harness.
Typically, in the office, we will scratch and
claw to get plans, and that's important.
Sometimes
on dam projects, especially, it's like either there
was a a fire in the powerhouse and
all the plans are gone, or there was
a flood and all the plans are gone,
or it changed hands enough and, you know,
there's there's no plans. So we have to

(13:57):
see if we can get those plans so
then we can figure out, okay, this this
high and, you know, it's this material type,
and these are the
details that could be problematic. I'd say that's
important
both from an access standpoint as well as
figuring out what to look for. Charlene said
they also review previous inspection reports so they
can look for previous findings such as cracks

(14:18):
and see how they've changed over time. Just
so I could have a mental note of
if there's anything I need to specifically focus
on. And, you know, we wanna make sure
that we document everything that was previously documented.
For example, if it's a spa just to
see if the spa got bigger or if
there was an exposed rebar before, there's exposed
rebar now. Basically, there's bookkeeping of all the

(14:39):
previous notes and expanding on those and any
new findings.
And I try to take as neat note
as possible just because following the inspection comes
the inspection report. It's better to get everything
out in the field rather than getting back
to the office and trying to figure out,
like, where this picture was taken. Because each
dam is designed to collaborate or at least

(15:01):
coexist with nature, there's not a one size
fits all approach to design. There's a lot
of different designs. Somehow, we didn't, like, just
design one, you know, radial gate and apply
it all over the country. A lot of
different designs out there where having some inspection
sheets is really helpful. It's sort of a
three d structure, and when you're in there,
just doing two d notes on a page,

(15:21):
if they're not planned out well, can turn
into a mess pretty quick. So I like
to get everything planned out either on inspection
sheets or sometimes an iPad. Before heading out
in the field, the team plans out the
gear they'll need and prepares a job hazard
analysis with a rescue plan in case of
emergency.
They also consider what technology they'll need, starting

(15:42):
with how they're handling documentation. We have folks
who take iPads out. We'll, you know, take
photos and actually
make their notes directly on the photo, which
is pretty cool seeing it back in the
office. Pretty time consuming in the field, so
there's a give and take there. You know,
pen and paper, obviously, writing the rain paper
specifically
with cameras. And then also just with some

(16:02):
of the NDE technology, a lot of that
goes to an external memory device where you're
able to save it and upload it and
and store it on the actual device that's
doing the readings. On smaller structures, it may
be a team of three that heads into
the field for an inspection.
A larger project may involve more than a
dozen inspectors.
For steel structures,

(16:23):
team members inspect every seam and rivet to
look for corrosion,
cracks, loose fasteners, deformations,
or any potential issues that could impact the
structure's integrity or affect operation.
They take measurements using calipers, ultrasonic thickness meters,
and a magnetic particle kits to determine how
much of the structure's material is left, whether

(16:45):
crack is present, and whether it's expanding.
On concrete structures, they investigate for cracks,
exposed rebar, seepage, or voids beneath the concrete.
They look for delamination
when the concrete begins to fracture into layers
beneath the surface,
as well as spalls,
which are flakes of concrete that begin to
chip off. Team members measure the joint offsets

(17:07):
and gaps and also evaluate the concrete slab
for uplift or cavitation
when empty pockets form beneath the surface.
We actually have a number of certified nondestructive
testing engineers who could come out to the
site and do, say, mad particle testing,
phased array ultrasonic testing, also just ultrasonic thickness
testing. So we have some NDE, which is

(17:28):
nondestructive evaluation
technicians who are who are able to to
come out into the field and basically try
to find
cracks and welds,
even get some better measurements on section loss
for steel members. For spillways, we've had some
ND folks come out to do ground penetrating
radar, pulse echo technology to try to figure

(17:48):
out if there's any voids beneath concrete slabs.
Travis said that often the job calls for
some combination of evolving technology
with some old school hands on inspection. So
whether it's using the ground penetrating radar or
impact echo or one of those other items
or even, doing some destructive testing like coring
and patching,
the core so we can get concrete strengths

(18:10):
and things. We're we're always looking for a
new tool.
So on that note, our our drone teams
are able to get, like, a broad spectrum
of, like, a lot of do the digital
twin and do the even image recognition and
finding changes, things like that. At this point,
they can't chip away at a a weld
and then, like, a fracture critical detail in
the gate that could be cracked or even
look into that weld. But it is getting

(18:31):
better, and we're always looking for, yeah, the
best tools that we can apply to the
project to really improve our probability of detection.
You know, whether that's just using a wire
brush and scraper
or, like, scanning the thing somehow, even with
LIDAR or other tool. For geologists like Mike,
inspection is less about the built structure itself.
We're more concerned with the foundation

(18:53):
materials, so what the concrete's poured on and
where the dam is sort of using as
a buttress for stability. And so we're after
just sort of the rock mass structure. We're
looking at a lot of the discontinuities in
the rock and, like, Travis had alluded to,
you know, weathered materials or broken up sections.
And so we'll focus on those areas to

(19:13):
try and quantify those. And, ultimately, it feeds
into some of its similar, some finite element
type stuff in terms of, you know, dam
stability. Understanding the impact of changing weather patterns
and erosion analysis
have also become an emphasis for geologists.
When I go out there and I'm looking
at the rock mass or some of the
soils that could be out there, it's telling

(19:34):
me a story. So there's, like, the geologic
story, which I always find fascinating. There's sometimes
pretty cool features in the rocks. Particularly out
here in California, there's a pretty active seismic
sort of component. So lots of folding and
faulting. So you get to see some pretty
cool rock formations. These rocks are kind of
fractured and kind of beat up. So those

(19:54):
are the areas that we're looking out for.
And in terms of trying to identify areas
that might be susceptible
to scour and erosion,
we would anticipate
to see some scour occurring during large flood
events. And if they're passing water over the
spillways and and trying to identify trouble areas
or if there could be a potential progression
that would undermine the stability of either the

(20:16):
spillway or the dam itself. Kenny explained how
the information gathered in the field supports the
technical analysis of the structure. In the office,
we do a lot of structural analysis, finite
element modeling for spillway gates and even spillways.
And this kinda helps us identify
stress concentrations
for specific gates
for looking at normal loading conditions, which ones

(20:38):
are overstressed.
And that can give us a a target
to really do a focused
in-depth inspection on those members since they're fracture
critical. Or if we're seeing signs in the
field of deformations relating it back to the
stress analysis
and trying to figure out why that's happening.
If there's a deformation in a flange, did
something hit it, or

(20:59):
is the the water service elevation too high
and and overloading
the the strut? With the added benefit of
having the same people working on the analysis.
The engineers and the EITs who are out
in the field doing the inspection
are actually the ones performing the analysis back
in the office. So there's a transfer of
information there that isn't lost because it's a

(21:19):
one to one individual, you know, doing it
in the field or the office. Our folks
are doing multipurpose
type projects where, you know, they're functioning as
the inspectors and the engineers doing the analysis,
and that's just a huge benefit. Travis noted
it also heightens the inspection team's awareness
of what to look for when they're covering
such a massive structure. Sometimes our inspections kinda

(21:41):
need to evaluate on the fly. So having
really qualified folks out there that have some
background in the dam safety realm to understand
the consequences
of when there are things going wrong and
what to look for. It's kept us from
missing things, I would say, and it's always
a risk that we don't find something. But
keeping your eyes open out there is really,

(22:01):
part of the job and and can change
the course of the whole project.
Even with all the the preparation and the
critical work to do, there's still a sense
of adventure once a young engineer
gets up on her first inspection. Charlene recalls
the feeling she had on her first big

(22:21):
dam, the nearly 100 foot high Williamson Dam
in Cisco, Texas.
Williamson Dam was really tall.
So I had that moment where I'm like,
okay, I'm actually doing this, and this is
really different from the training center. And
it was pretty much the first time I

(22:42):
got to
inspect one of the dams that we do
analysis and
so, like, the building analysis, and then we
work on so much. So
that was, like, the first time I was
out there, and I got to actually, like,
feel the size of the dam and this
huge structure.
Depending on the type of job, you can
be up on the ropes for a long
time, which requires some planning to stay fueled.

(23:05):
Definitely some Clif bars. I try not to
drink. It's like a a battle of
staying hydrated and not drinking too much because
using the bathroom for me is a little
more work.
So Gatorade for sure.
I somehow always manage to get some oranges.
I sneak in some cookies in there too.
It's usually

(23:26):
really hot.
And a lot when you're moving around a
lot, it's just a matter of when you're
getting tired. Typically,
technicians spend a lot longer time in the
air on a bridge project as Kenny experienced
on an inspection of the Golden Gate Bridge.
On the bridge side, it could be pretty
difficult, you know, going back to the Golden
Gate. We're only allowed to enter on one

(23:47):
side
and exit on one side. And so just
doing a floor beam takes,
I don't know, two to three hours, and
then coming back doing another floor beam takes
two to three hours.
And so that's why on the bridge side,
you're usually taking food with you. So you
could be suspended
twelve hours. And so my lunch at Golden
Gate consisted of a a pack of raisins

(24:09):
and a cliff bar. It's usually a slightly
different story on a dam where you're in
a remote location away from the public and
descending down from the deck level.
Travis is quick to point out the perks.
Our lunches are definitely better on the on
dams.
That's ridiculous. Yeah. You know, on on a
bridge, you sort of get out there. You
get traffic control. It takes a while to

(24:30):
get up on the structure, and you're sort
of there quite a bit of the day.
With dams, you know, we rappel down, and
then we we can hike back up to
the deck. And we can just, you know,
pull a cooler right out there under the
deck, and we typically like to get some,
you know, get the deli meat going, maybe
some fancy cheeses, and get
get, get parked out there on the dam.
Besides, it's it's a beautiful area typically that

(24:51):
we're in, some, you know, canyon or something.
Sometimes they do even better than that. My
lunch at Lake Matthews consisted of DoorDash where
we got Mediterranean food one day, Thai food
the other day. And, it's always a running
joke within the rope access program that the
bridge guys kind of, you know, nudged at
us a little bit on how good our
our lunches are. But that doesn't stop Travis

(25:12):
from being creative on a bridge job. I
seem to remember one day we ordered pizza
at a bridge, and we had to get
it sent up from a boat. And the
guy operating the boat threw the pizza, like,
in a bag and then just, like, hoisted
the bag to the rope. There was no
preparation on delivery method there on on his
part, unfortunately.
And so we got the pizza at the
top of the bridge. It's just a pile

(25:32):
of pizza.
In addition to the fun stories about what
they bring to lunch,
Mike has one involving what he brought to
dinner. Once again, being a geologist, we're kinda
out tromping around. So some of these spillways
have little, you know, drainages on the side.
And since I'm after the foundation conditions, I
gotta go poke my head around on the
outside of the concrete, and
sometimes that entails walking through some vegetation and

(25:56):
picking up some travelers.
There's that one time we were doing a
a job down on the coast here, and
there was a nice little stream, some vegetation.
I had sprayed myself with, like, the bug
spray and everything. So I was like, alright.
I'm feeling pretty good here.
No snakes. You know? Always gotta watch out
for snakes. And then we get to dinner
later that night, and I got a tick
crawling right on my arm.

(26:18):
And I remember we're sharing a table with,
like, a couple. This was pre COVID.
And they noticed it, like, crawling down my
arm and onto the table, and I think
I ended up pulling, like, three of them
off before I think I got all of
them.
So definitely the wildlife is something to keep
an eye out for. In fact, Travis explained
why a dam makes a perfect home for

(26:38):
wildlife.
My father was a wildlife biologist, so I
have kind of an affinity for kriggers out
there. That living in infrastructure,
One of the first projects, Georgia Power, there
was so much water that was coming over
the spillway gates or through this, you know,
leaky's old side seals. And at these hydropower
plants, they wanna keep the water as high

(26:58):
as possible, right, so they can generate electricity.
But it also means that there's lots of
vegetation
under there. So it can be like a
jungle inside the girders. So we have some
pretty spectacular
documentation of vegetation within these these gates, huge
ferns and different things. Meaning the team needs
to be prepared
for a lot more than ticks. Whether it's

(27:18):
snakes. So water moccasins like to be in
that area in Georgia. So we got snakes
on dams. And, I know we've run into
some raccoons and different things in there. I
went into one area and saw a ringtail
cat in Texas.
And then, I know we've had some, run
ins with raptors
as well. So often we if we find
a big nest or something, we'll just avoid

(27:40):
the area and try to come back when
they're not nesting or something. But they can
get pretty ornery with us. They they're sort
of territorial and can, you know,
do a little bit of dive bombing, stuff
like that. And then I I know the
army corps had a picture of a a
a black bear on one of the big
radio gates on the Columbia River. It was
just perched up there on the on the
gate. The terrain itself around the dam can

(28:01):
also add to the adventure
as well as the hazards, especially for the
geologists.
I'll say those the structure guys have it
easy. Everything is all concrete
and relatively flat. And, I won't say smooth,
but everything's kind of a little more manageable.
Once you get over the edge of the
concrete and onto some of these online portions
or the abutments, I mean, you're dealing with

(28:23):
all sorts of overhangs and craggy rocks, loose
rocks. So it kinda
it's not usually as steep, which ends up
being a little trickier because you kinda it's
all about, like, rope management and trying not
to step on stuff or hooking on things,
and it's a little easier when everything's just
kind of up and down, and it all
just falls to your side. When the water

(28:43):
level at the dam is being kept high
to provide hydropower,
it can add additional excitement for the inspectors.
What happens when the water near the top
of the gates is that sometimes there can
be some wind, and what that causes is
small waves. But when those small waves right
up on the gate, they can be like
a wheelbarrow full of water. And if you're
on the downstream side of the gate, given

(29:04):
it was hot and it was kinda nice,
you know, to get drenched every once in
a while, but when you're in the middle
of, like, writing a note and then get
hit by, like, a wheelbarrow full of water,
It can,
kind of, shake you up a little bit.
Kenny recalled a job where a new colleague
started getting hit by the waves. I remember
he found something, and so he was trying
to talk to me. And it was literally
every five seconds,

(29:25):
a bucket of water would land on him.
And so he would say, hey, Kenny.
He got he got hit with a wave.
I found something down here, and then he
would get hit with a wave again.
And he literally just had to move 15
feet, so so he cannot get hit with
a wave. But it it took him a
couple of minutes to figure that one out.
So it's it's pretty funny. But, yeah, like
Travis said, if it's hot, it actually feels

(29:45):
pretty good. The actual work they're doing is
interesting as well. In February
2017,
the main spillway failed at California's
Oroville
Dam, the tallest dam in The United States.
The dam provides drinking water, hydroelectric
power, and flood control near Folsom, California. Now
the integrity of a major dam in California

(30:07):
comes under threat after days of historic rainfall.
He news in Northern California tonight, tens of
thousands forced to evacuate tonight due to concerns
the Oroville Dam's emergency spillway
could fail.
Good evening, everybody. The water was spilling over
into this emergency or auxiliary spillway. About 03:00,
this afternoon, engineers who had been monitoring the

(30:29):
situation there noticed that there was some sort
of erosion on that emergency spillway. With water
thundering out of Oroville Dam, Officials are in
a race to fix the damaged spillway
and lower the lake level, which is at
near capacity. At one point, officials said if
that emergency spillway breached, a 30 foot wall
of water could cascade into communities downstream. Now

(30:51):
this is Kenny remembers the moment a colleague
told him the news. He came to my
office, and he said, hey, Kenny. Something's going
on at the spillway. Can you grab some
tools
and meet me out there?
And, you know, I I I had a
bunch of questions, and he is pretty much
like, that that's all the information I have,
so bring whatever you think is necessary.
And so I I grabbed some tools from

(31:11):
what I thought it was and drove out
to the site.
And as soon as I got there, I
I said, yeah. Everything I brought is gonna
be useless. Rainfall had raised the water level
on the lake, and the heavy flow began
to erode away the main spillway that controls
flows downstream.
It eventually created a 300 foot crater. After
the California Department of Water Resources closed the

(31:34):
spillway, the high water level overtop the emergency
spillway, which also began to erode.
Concerned for a potential dam failure and catastrophic
flood, the state evacuated a 88,000
people from their homes. I was ultimately the
first person that went down into the hole,
and that was something that a lot of
people will probably never get the opportunity to

(31:54):
do again. And, you know, knock on wood,
I'm not gonna be able to do it
again. But it was just fascinating
at the amount of engineers who really took
pride
and wanted to develop plans to fix the
spillway, you know, emergency action plans that were
being developed
real time and just working with a a
great number of folks here at HDR, at

(32:14):
DWR, and a number of other consultants that
were out there. You you know, just really
showed that the community, the engineering community came
together. More than 50 HDR staff mobilized and
began working alternating twelve hour shifts, seven days
a week, to monitor and report on the
condition of the spillway
to help DWR
form an emergency response. Travis was also among

(32:37):
the first responders.
Just walking the spillway
in the middle of the night with a
radio and a flashlight,
And then the next day, not knowing if
they need us to go climb gates again.
There was a dam downstream that we needed
to go look at as well to make
sure that was okay and just kinda being
at the ready all the time. And Kenny
and I were monitoring leads out there. So

(32:59):
we have a team, a crew during a
shift, and it was pretty pretty wild dynamic
situation. The emergency response, temporary repairs, and reconstruction
of the spillway
eventually cost more than $1,000,000,000.
A greater catastrophe was averted,
but it further highlights the importance of inspecting
and maintaining infrastructure.
Some small offset like in a spillway with

(33:22):
high velocity flow can be catastrophic when it
comes to, you know, the integrity of the
structure. Oroville was an example of that. We
don't know what kinda joint offset or anything
it may have had, but one small defect
became an unraveling there. I would say that,
you know, during the inspection, sometimes we're there,
and I had an old slab and buttress
dam and, know, look at some rock fall
issues and things. We started looking at the

(33:43):
underlying
buttresses of this Amerson stop, all dam.
And they had some pattern cracking, some, like,
sheer type cracks. And and then we also
saw some issues with the outlet works where
there were separated flow flanges
in the in the piping at high head
situations and, yeah, just kinda unraveled some additional
findings at the dam. We're like, you know

(34:04):
what? This needs a this needs a bigger
look. So we recommend, you know, a follow-up
and then ultimately, you know, some interim risk
assessment
stuff as they plan to either, retrofit significantly
or replace the dam. The Oroville Dam incident
also caused dam owners and regulatory agencies to
reassess their aging infrastructure.
Where are spillway dams that are high risk?

(34:26):
And some of the dams that are over
highly populated areas, we took a little more
time with and did rope access
inspections along with some ground penetrating radar, and
we used
some pipe inspection methods to look at the
drain systems underneath these spillways.
So we really overlaid, like, a lot of
different methods to try to find defects. Travis

(34:48):
and Mike shared an example that they worked
on in Southern California.
I led a team doing rope access inspections
of everything, and we got essentially with arms
reach of all the component.
So the the spillway itself, you know, the
gate structure, the the walls on the sides,
and we rig ropes, like, horizontally to traverse
and to get those. So we had to

(35:08):
install some concrete anchors to do that. And
then down at the flip bucket, we looked
at that. At phase two was the destructive
testing or drilling, that we did. And so
there's a big drilling program out on the
emergency spillway, but, also, I think we ended
up doing 20 some odd holes, 26 holes
maybe in the service spillway. And these were
targeting areas that were identified on the GPR

(35:30):
results that as anomalies or areas that might
the slab might be a little thinner than
design or maybe some delaminations
or cracking. Kenny mentioned an inspection in the
Pacific Northwest,
another job that helped avert more serious consequences.
And, basically, we're inspecting the gates, and we
saw some what Sam Plank actually said was
one of the one of the worst deformations

(35:51):
he'd seen on a on a strut arm.
And so
if one of those were to fail
or become overly distorted, there could be a
failure of your gate and a uncontrolled release
of your reservoir so you'd be losing a
lot of water. And so
we were awarded an emergency analysis
contract where we did the finite element analysis

(36:11):
of the gate, and the core actually went
in and did an emergency
retrofit
of those gates just because of the items
that we saw in the field and how
concerning they were. So it was
it was really rewarding in the sense that,
you know, our inspection findings led to a
major finding that could have been disastrous and
being able to be part of the team

(36:32):
that developed
the the retrofit plans and specifications
and ultimately got it constructed.
With aging infrastructure,
limited funding, and outside forces like climate change

(36:52):
and increasing water demands,
dam owners face mounting pressure
to not only meet community needs,
but to prevent a catastrophic
failure. I think the realization
is that a lot of our infrastructure
is 50 to a hundred years old, if
not greater. So just understanding
that all of these structures have a set

(37:12):
lifespan, you can't expect things to last forever.
And so keeping up on proper maintenance or
retrofits to at least extend the life, but
ultimately, at some point, starting to think replacement,
I think that's going to be one of
the, the big items that will come up
here in the future. Climate change specifically is
changing the equation for which infrastructure was originally

(37:33):
designed. We are updating
potential maximum precipitation
analysis. So, essentially, how much is a big
storm going to generate and then potential maximum
flood routing, how much is this storm, what
type of flood is it going to make?
And is that going to jeopardize the dam?
And how do we size for that? Those
are all related to climate change and then

(37:53):
also related to sea level rise. Mike said
the convergence
of many factors means the industry can't be
comfortable with the status quo. There's definitely an
intersection there between
the age of our infrastructure
and then some of these sort of larger
forces at play, the climate change and whatnot.
We could definitely stand a little more investment
on that front, I think. And

(38:14):
while
fixing things and and sort of maintaining what
we've got is is good as we move
forward too. You you have
to take into account some of these other
forces like climate change so that you don't
find yourself in a worse position
than when you started. And so
there's gonna be some pretty large implications.

(38:34):
Travis cited a local project example. We've seen
locally here in Colorado small watersheds that are
for show five times the potential flow than
they did, you know, pre fire. So we
could get all kinds of debris, and and
it becomes a potential dam safety concern. I
think one area, it said the hydraulics on
it said, one over 70,000
chance of overtopping

(38:56):
pre fire. Post fire, it's about one over
500.
So it it can, you know, jump up
pretty fast there in the, you know, how
how resilient these structures are when affected by
a natural disaster. Kenny said all the work
contributes to a bigger picture. There's a number
of other analyses that go into this. There's
potential failure modes. There's level two risk analyses.

(39:16):
And so, really, a lot of the information
that we're gathering out in the field are
help feeding these other types of analyses.
And I've said this to multiple clients and
just even family members. The ultimate
endgame here is that we want the structure
to be safe because it's protecting anywhere from
one person to hundreds of thousands of people

(39:38):
behind it. We're here to make sure that
the the structure
is in adequate condition so those people feel
safe. And so it always plays a role
when we're out in the field. If something
takes an extra two hours, let's get it
done. If it's gonna give us some answers
or just make us feel more confident on
the behavior of the structure. Mike offers an

(39:58):
even more
philosophical perspective. When it comes to
the geology, usually, we're talking time scales of
several thousands of years to millions of years.
Right? And so how do you make that
relevant to present day and and some of
these structures and the work we're doing? And
so that's where I kind of also find
some of the meaning and just acknowledging that

(40:19):
the rocks are there to tell you a
story, but we've engineered around it to provide
these reservoirs for drinking water irrigation
and all the folks downstream. So it kinda
helps bring it full circle to to why
we do this kinda work and making sure
that we've got safe and competent infrastructure.
That role puts the rope access inspection team

(40:40):
on the front line of dam safety every
day. I guess the rope access team is
sort of a infrastructure first response when it
comes to imaged components.
Being that trusted responder for clients when they
need help has paid dividends across the board,
not only in more inspection work and stuff,
but helping them respond to it in a

(41:00):
long term. Jarlene recognizes
the significance
of that role every time she's on the
job and discovers a crack, corrosion, or seepage
that might tell a larger story. Like, always
inspecting with the thought of when you find
a defect, like, was this something that happened
during construction, or is this something that's happening
because something's wrong with the structure? And if

(41:21):
it is something wrong with the structure,
what's causing it? Is it gonna get worse
over time? Like, you just always go in
there with the mindset of trying to figure
out the issue and
how to fix the issue and any potential
risk that could happen.
I think that's always in the back of
my mind.

(41:41):
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