Barotrauma in riverine fish: pathways, tools for ... · for estimating survival, and implications for hydropower Richard S. Brown Pacific Northwest National Laboratory Richland, Washington,

Barotrauma in riverine fish: pathways, tools for estimating survival, and implications for

hydropower

Richard S. Brown

Pacific Northwest National Laboratory

Richland, Washington, USA

1

Background

2

Turbine passage guidelines are needed for many fish species

Many turbines in North America are aging and need replacing

Opportunity to improve passage survival

US Department of Energy has a goal to add turbines to existing structures

Lack of information on turbine survival is slowing

New hydro projects in many countries

A large variety of fish would pass turbines

Hydroturbine passage – Sources of injury

Mechanical

strike

• Bruising

• Cuts

• Rupture of

blood vessels

Shear forces

• Bruising

• Cuts

• Gill damage

• Eye damage

Rapid decreases in

pressure

• Ruptured swim

bladder (bexiga

natatoria

• Eye pop

• Bubbles in fins,

gills, internal

organs

• Rupture of blood

vessels

Barotraumas

Hydroturbine passage (both large and small hydro)

All fish are exposed to pressure changes

Less likely among

small fish than

big fish

Bear-o-trauma??

5

Far Side

Barotrauma ►Damage to fish due to changes in barometric pressure

►Occurs in fish during rapid decompression

►Damage to fish when brought to the surface during angling

►Similarities to effect a diver would experience with the Bends

6

On the back side of

turbine blades –

pressure as low as 0

kPa absolute

Typically ~50 kPa or

higher

We feel ~ 100 kPa

Survival estimates

70% – upper 90’s%

Barotrauma

7

Pressure changes during turbine passage Cross section of a typical Columbia or Snake River dam

Pressure profile is example. Pressures vary for each fish.

Spike data Path of fish

0 10 20 30 40

Time (s)

Forebay Penstock Turbine Draft tube Tailrace


Putting pressure change into context

8

~28 kPa or ~4psi

~400 kPa or ~58psi (~30m depth)

~150 kPa or ~21 psi

9

Causes of barotrauma: Henry vs Boyle

Gas coming out of solution blood (governed by Henry’s

law)

■ Example: bubbles coming out of soda

Water cannot hold gas when pressure is reduced to 0 kPa

Similarities to the Bends but divers breath compressed gas

Expansion of existing gas (governed by Boyle’s law)

■ Example: balloon expanding when pressure decreases

■ The swim bladder is similar to a balloon in a fish

swim bladder (bexiga natatoria) of a

Juvenile Chinook salmon

Pre

ssure

breathing

compressed

gas

gas comes

out of

suspension

as pressure

decreases

free diver

not breathing

compressed

gas

no gas comes

out of

suspension

as pressure

decreases

when surfacing

salmon not

taking in

compressed

gas

gas comes out of

suspension as

pressure

decreases closer

to 0 psia

blood becomes

supersaturated

more gas comes

out of

suspension

Open swim bladder

Physostome

Closed swim bladder

Physoclist

No swim bladder

Pressure related injury varies with type of fish

Swim bladder Swim bladder opening

(pneumatic duct)

The swim bladder (bexiga natatoria) is used to regulate buoyancy

Fish with an open swim bladder (physostome) have a duct that

controls gas

Fish with a closed swim bladder (physoclist) regulate using gas

from blood

■ They have a rete or bed of blood vessels to exchange gas (but physostomes

may too)

Open swim bladder

Physostome

Closed swim bladder

Physoclist

No swim bladder

young fish pneumatic duct vary from older fish

Boyle’s Law effects swim bladder volume

14

Gul

ping

Descending

Neutral Buoyancy

Surface

Sw

im b

ladd

er vo

lum

e

Dep

th a

nd

pre

ssu

re

Pressure1 Volume1= Pressure2 Volume2

15

Expansion of gas

Boyles law – every 1/2 pressure = 2 X volume

The ratio of pressure change is important

not the absolute pressure change

Pressure1 * Volume1= Pressure2 *Volume2


0 10 20 30 40

Time (s)



Acclimation depth effects barotrauma during turbine passage


0 10 20 30 40

Time (s)


20 kPa


420

350

280

210

140

70

0

Ab

solu

te p

ress

ure

(k

Pa

)

4 m

140 kPa

8 m

180 kPa 700%

increase

900%

increase

18

Common injuries due to pressure decrease

Bubbles in eyes, fins and gills

Ruptured swim bladder

Stomach pushed out of mouth by swim bladder

Exopthalmia

Exopthalmia (eye pop) and

ruptured blood vessels

19

Mobile Aquatic

Barotrauma Laboratory

(MABL)

Laboratory testing

For details see Stephenson et al. 2010. Fisheries Research

20

Determining relationship between pressure change and fish damage

► Hyper/Hypobaric chamber capable

380 to < 10 kPa in < 0.25 sec

► Large numbers of juvenile Chinook

salmon exposed (5713)

► Fish acclimated to a wide range of

pressures pressure (115-175 kPa)

► Fish exposed to a wide range of

pressures (continuous from ~20-80

kPa)

► Wide range of fish size and condition

► Total dissolved gas 105-125

21

Relationship between pressure change and fish mortal injury

Example:

Fish going from

5 m (~150 kPa)

to 50 kPa in turbine

Has ratio pressure change

of 3 (150/50=3)

Brown et al. 2012a. Transactions of the American Fisheries Society

22

Causes of barotrauma: Henry vs. Boyle

Gas coming out of solution (governed by Henry’s law)

■ Example: bubbles coming out of suspension in soda

Water cannot hold gas when pressure is reduced to 0 kPa

Similarities to the Bends

Expansion of existing gas (governed by Boyle’s law)

■ Example: balloon expanding when pressure decreases

Fish with less gas in their swim bladder experience lower mortality

Stephenson et al. 2010. Fisheries Research 106:271-278

Neutrally Buoyant

Negatively Buoyant

0 34.5 68.9 103.4

Nadir (kPa) Nadir (kPa)

0 34.5 68.9 103.4

0

20

40

60

80

100

0

20

40

60

80

100

Sw

im b

lad

der

ru

ptu

re (%

)(a)

(b)

Mo

rtal

ity (

%)

(c)

Inte

rnal

hem

orr

hag

ing

(%) (d)

Gill

em

bo

li (%

)M

ort

ality

(%

)

0 35 69 103

Lowest pressure (kPa)

Neutrally buoyant

Negatively buoyant

More gas

Less gas

24

Rupturing of the swim bladder (bexiga natatoria) plays an important role for salmonids

Emboli more likely among

fish with a ruptured bexiga

natatoria

Brown et al. 2012b Fisheries Research

Exopthalmia and hemorrhaging

more common with ruptured bexiga

natatoria

25

Rapid decompression: gas from ruptured swim bladder and expulsion through the pneumatic duct

X-rays of salmon show channels of bubbles leading from ruptured swim bladder

Gas from swim bladder bursting

blood vessels, popping eyes out,

pushing bubbles into vessels


Light colored areas indicate gas

27

Bubbles from gas in swim bladder visible in fins

A A

28

Force of swim bladder rupture

Work conducted in 2005 examining damage due to transmitter presence

Juvenile Chinook salmon decompressed from 161 to 11 kPa

Ratio pressure change of 14.6; LRP 2.7

Transmitter expelled from stomach at a velocity of 4.5 m/s

29

Slow vs rapid decompression in salmon

When decreased slowly to 14 kPa and then returned to surface

■ No mortality

■ Salmon expel gas from swim bladder / no rupture


30

Slow decompression: gas expulsion through the pneumatic duct

31

Rapid decompression in salmon leads to mortality

When decreased slowly to 14 kPa and then returned to surface

■ No mortality

■ Salmon expel gas from swim bladder / no rupture

When decompressed rapidly, the swim bladder ruptures

■ Injury and mortality

■ Variable amount of gas expelled from swim bladder (fish expelling

more gas are likely to have less injury)

Brown et al. 2012b. Fisheries Research

32

High variability likely due to gas expulsion from swim bladder during decompression


Fish that did not expel

gas from swim bladder:

swim bladder ruptured

Fish that did expel

gas from swim bladder

33

Gas coming out of blood not likely cause of

injury during turbine passage

Fish slowly decompressed to low pressure (no ruptured SB)

Salmon died after a median of 3 min (range 2.2-7.0) at 14 kPa

Lamprey (have no swim bladder) uninjured after 17 minutes at low

pressure

Lamprey are primitive and have a unique respiratory system

Swim bladder expansion and rupture important

Need to know how much gas in fish when approaching turbines

Colotelo et al. 2012. Fisheries Research

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15

Mo

rta

lly

In

jure

d (

%)

Ratio Pressure Change

Juvenile Chinook

Acc: 5m (150 kPa)

Nadir: 50 kPa

RPC: 3 (150/50=3)

Burbot

Acc: 40m (400 kPa)

Nadir: 50 kPa

RPC: 8 (400/50=8)

Mortal injury: dead or have injuries statistically

shown to be likely to lead to death Pflugrath et al. 2012 Transactions of the

American Fisheries Soc.

Acclimation pressure / lowest exposure pressure

Barotrauma susceptibility index – how to prioritize work in US, SE Asia……. – more research needed

Amount of undissolved gas in the body

Swim bladder morphology, rete activity level, pneumatic duct

The pressure exposure

Acclimation depth, exposure pressure, ratio pressure change and rate of ratio pressure change

Life history

Migratory, larval drift

Structural integrity

Low for small fish Screens can be used but not on larvae

35

Hybrid huso x amur sturgeon

Photo by Dr. Gao,

China Three Gorges Corporation

Chinese Sturgeon Institute

white sturgeon

Photo by Jason McLellan,

Confederated Tribes of the Colville Reservation

36

Will fish with closed swim bladders be different than fish with open swim bladders?


Fish that did not expel

gas from swim bladder:

swim bladder ruptured

Fish that did expel

gas from swim bladder

Possibly much lower numbers of fish needed for testing

Physoclists???

Success story

Turbine replacement at Ice Harbor Dam

Barotrauma data from PNNL

Turbine design by Voith

New turbines with lowest pressure ~15psia (surface

pressure)

Doing tests now with new externally attached neutrally

buoyant transmitter

Bias from internal implants

Carlson et al 2012, TAFS

Post replacement tests

37

38

Bias in survival estimates of turbine passed fish

Main tools are balloon tags, acoustic or radio telemetry, lab studies

Balloon tags may provide a good indication of likelihood of strike or damage due to shear

Studies have not included acclimated fish

Estimates of survival likely lower than acclimated fish

Similar problems with some lab studies

Fish internally implanted with transmitters have higher likelihood of barotrauma than untagged fish

Carlson et al 2012, TAFS

39

Laboratory testing with fish

~11,000 fish exposed

Wide range of pressure change

Wide range of fish size

Wide range of tag burden

JSATS Juvenile Salmon Acoustic

Telemetry System……

….not just for salmon

40

Implanted transmitters lead to bias in survival estimates through turbines

Ratio pressure change (ln)

0 0.5 1 1.5 2 2.5 3 3.5

Pro

ba

bilit

y o

f m

ort

al in

jury

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Tag Burden = 0.0

Tag Burden = 2.0

Tag Burden = 3.5

Tag Burden = 5.0

Tag Burden = 7.0

Ratio pressure change

1 2.7 7.4 20.1

20%


0 0.5 1 1.5 2 2.5 3 3.5

Pro

ba

bilit

y o

f m

ort

al in

jury

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Tag Burden = 0.0

Tag Burden = 2.0

Tag Burden = 3.5

Tag Burden = 5.0

Tag Burden = 7.0


1 2.7 7.4 20.1

20%

46%


0 0.5 1 1.5 2 2.5 3 3.5

Pro

ba

bilit

y o

f m

ort

al in

jury

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Tag Burden = 0.0

Tag Burden = 2.0

Tag Burden = 3.5

Tag Burden = 5.0

Tag Burden = 7.0


1 2.7 7.4 20.1

20%

46%

68%


0 0.5 1 1.5 2 2.5 3 3.5

Pro

ba

bilit

y o

f m

ort

al in

jury

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Tag Burden = 0.0

Tag Burden = 2.0

Tag Burden = 3.5

Tag Burden = 5.0

Tag Burden = 7.0


1 2.7 7.4 20.1

20%

46%

68%

84%


0 0.5 1 1.5 2 2.5 3 3.5

Pro

ba

bilit

y o

f m

ort

al in

jury

0.0

0.2

0.4

0.6

0.8

1.0

1.2

Tag Burden = 0.0

Tag Burden = 2.0

Tag Burden = 3.5

Tag Burden = 5.0

Tag Burden = 7.0


1 2.7 7.4 20.1

20%

46%

68%

84%

95%

Ratio pressure change =

Acclimation pressure

Nadir pressure

5 m = 150 kPa

Nadir = 50 kPa

Ratio pressure change = 150 kPa = 3 50 kPa

Bias high in middle of range – low on

either end of range 27 g fish (0.53g PIT and JSATS) 11g fish

8g fish

Accuracy is important for entities with regulatory limits

Tag excess mass increases swim bladder volume

42

Tag bias likely

Tag bias is likely present

Higher bias with larger tags / tag burden

Suggest using smallest tag - new downsized JSATS tag

Higher bias with mid-range pressure changes

Previous research likely underestimated survival

Neutrally buoyant external tag

Deng et al. 2012. Fisheries Research

44

Tag design

Relatively short life span

Survival through a single powerhouse

Engineering team at PNNL examined

CAD Model

Neutrally buoyant external tag – lab testing

►Low tissue response

► Injuries when exposed to shear were similar to untagged fish

►Swimming performance similar to internally tagged fish

►Likelihood of predation similar to untagged fish

►Likelihood of barotrauma similar to untagged fish

Deng et al. 2012 Fisheries Research

Janak et al. in press Transactions of the American Fisheries Soc.

Brown et al. 2012c J. Renewable and Sustainable Energy

Neutrally buoyant external transmitter Field testing of survival– currently underway

46

Top down view

►Compare internal implants to

externally tagged fish

►Compare exposed to unexposed

Other new technological advances at PNNL

47

Sensor fish is being downsized by Daniel Deng

Used to measure pressure, shear and

turbulence

Data can be used for lab research

JSATS tags (current on right; 0.3g)

Are being downsized (estimated ~0.2g)

and injectable

PNNL researchers downsizing battery,

transducer and other components

Specialized for work around hydro dams

including very accurate 3D

For more info on JSATS

McMichael et al. 2010. Fisheries

Cooperation is the key to rapid advancement

Many species to study

Species with diverse traits and life history

Swim bladder structure

Variable ability to add gas to swim bladder from blood

Structural integrity

Science can advance faster with cooperation

Work to minimize impacts to fish

48

Acknowledgments

U.S. Army Corps of Engineers Portland and Walla Walla Districts

Symbiotics LLC

Staff of the Pacific Northwest National Laboratory

Staff of the Columbia Basin Research, School of Aquatic Resources, University of Washington,

The USACE Turbine Survival Technical Team

Staff of New South Wales Department of Primary Industries

CEMIG

Photo of PNNL Barotrauma

Researcher John Stephenson

References

Brown, R. S., T. J. Carlson, A. J. Gingerich, J. R. Stephenson, B. D Pflugrath, A. E. Welch, M. J. Langeslay, M. L. Ahmann, R. L. Johnson, J. R. Skalski, A. G. Seaburg, R. L. Townsend. 2012a. Quantifying mortal injury of juvenile Chinook salmon exposed to simulated hydro-turbine passage. Transactions of the American Fisheries Society 141:147-157.

Brown, R. S., B. D. Pflugrath, T. J. Carlson, and Z. D. Deng. 2012c. The effect of an externally attached neutrally buoyant transmitter on mortal injury during simulated hydroturbine passage. Journal of Renewable and Sustainable Energy 4, 013107 (2012); doi:10.1063/1.3682062.

Brown, R. S., B. D. Pflugrath, A. H. Colotelo, C. J. Brauner, T. J. Carlson, and Z. D. Deng. 2012b. Pathways of barotrauma in juvenile salmonids exposed to simulated hydroturbines passage: Boyles Law vs. Henry’s Law. Fisheries Research 121-122:43-50.

Carlson, T. J., R. S. Brown, J. R. Stephenson, B. D. Pflugrath, A. H. Colotelo, A. J. Gingerich, P. L. Benjamin, M. J. Langeslay, M. L. Ahmann, R. L. Johnson, J. R. Skalski, A. G. Seaburg, and R. L. Townsend. 2012. The Influence of Tag Presence on the Mortality of Juvenile Chinook Salmon Exposed to Simulated Hydroturbine Passage: Implications for Survival Estimates and Management of Hydroelectric Facilities. North American Journal of Fisheries Management 32:2, 249-261.

Colotelo, A. H., B. D. Pflugrath, R. S. Brown, C. J. Brauner, R. P. Mueller, T. J. Carlson, Z. D. Deng, M. L. Ahmann, and B. A. Trumbo. 2012. The effect of rapid and sustained decompression on barotrauma in juvenile brook lamprey and Pacific lamprey: implications for passage at hydroelectric facilities. Fisheries Research 129-130:17-20.

Deng, Z. D., J. J. Martinez, A. H. Colotelo, T. K. Abel, A. P. LeBarge, R. S. Brown, B. D. Pflugrath, R. P. Mueller, T. J. Carlson, A. G. Seaburg, R. L. Johnson, M. L. Ahmann. 2012. Development of external and neutrally buoyant acoustic transmitters for juvenile salmon turbine passage evaluation. Fisheries Research 113:94-105.

Janak, J. M., R. S. Brown, A. H. Colotelo, B. D. Pflugrath, J. R. Stephenson, Z. D. Deng, and T. J. Carlson. In press. The effects of neutrally buoyant externally attached transmitters on predation avoidance and swimming performance of juvenile Chinook salmon. Transactions of the American Fisheries Society.

McMichael, G A., M. B. Eppard, T. J. Carlson, J. A. Carter, B. D. Ebberts, R. S. Brown, M. Weiland, G. R. Ploskey, R. A Harnish, and Z. D. Deng. 2010. The juvenile salmon acoustic telemetry system: a new tool. Fisheries 35(1):9-22.

Pflugrath, B. D., R. S. Brown, and T. J. Carlson. 2012. Maximum acclimation depth of juvenile Chinook salmon: implications for survival during hydroturbine passage. Transactions of the American Fisheries Society 141:2, 520-525.

Stephenson, J. R., A. J. Gingerich, R. S. Brown, B. D. Pflugrath, Z. Deng, T. J. Carlson, M. J. Langeslay, M. L. Ahmann, and R. L. Johnson. 2010. Assessing decompression in fishes using a mobile aquatic barotrauma laboratory: case study examining the incidence of barotrauma in neutrally and negatively buoyant juvenile salmonids exposed to simulated hydro-turbine passage. Fisheries Research 106:271-278.

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Documents

Barotrauma in riverine fish: pathways, tools for ... · for estimating survival, and implications for hydropower Richard S. Brown Pacific Northwest National Laboratory Richland, Washington,