Fish passage Development in Lao PDR

Workshop on Fish and Hydropower
16-17 June 2015, Vientiane
Fish passage Development
in Lao PDR
By: Douangkham Singhanouvong
Dr. Oudom Phonekhampheng
Mr. Garry Thorncraft
Dr. Lee Baumgartner
Mr. Tim Marsden
Dr. Craig Boys



Why fish passage need to be studied in
Lao PDR
What we have been done so far on fish
passage in Lao PDR
What will we do in the future?
Why fish
passage need to
be studied in
Lao PDR
Upstream Fish Migration
 Down stream Fish Migration

For Upstream Fish Migration:


The first pilot on fish passage experiment for low
weir was conducted since in 2008 and 2009 in
Pakpeung wetland, paksan district, Bolikhamxay
Province
Since 2011-2015 the experiment has been carried
out in Pakpeung wetland and Huyxai weir,
Xayphouthong district, Savannakhet province and
both phases support by ACIAR
Location - Overhead
Pak Peung Regulator
Study site
Pak Xan District
Bolikham
say Province
1. Fishway designs (V-slot, Sub Orifice,
Rock ramp)
Two locations:
Savannahkhet; Huai Xai regulator Pak San; Pak Peung regulato





Three treatments: v-slot, sub o (15), sub o (30)
Fisherman control
Latin-square design (two days to complete)
Three hour trap sets
All fish captured were weighed, measured and
identified
Catch summary (top 10; day)
Fisherman
Sub 15
Sub 30
V-Slot
Grand
Total
Crossocheilus atrilimes
23 (0.104)
437 (1.648)
575 (2.231)
548 (1.989)
1583 (5.972)
Thynnichthys
thynnoides
290 (6.929)
572 (10.767)
118 (2.464)
260 (5.777) 1240 (25.937)
Rasbora aurotaenia
310 (1.578)
57 (0.333)
166 (0.689)
98 (0.484)
631 (3.084)
Parambassis siamensis
64 (0.125)
78 (0.088)
173 (0.221)
196 (7.792)
511 (8.2266)
Hypsibarbus lagleri
325 (3.374)
34 (0.143)
33 (0.0975)
31 (0.149)
423 (3.7635)
Osteochilus lini
37 (0.623)
157 (3.170)
37 (0.47)
109 (0.752)
340 (5.015)
Cyclocheilichthys
repasson
256 (3.860)
16 (0.241)
4 (0.038)
0
276 (4.139)
41 (0.205)
38 (0.135)
46 (0.188)
73 (0.257)
198 (0.785)
103 (1.19)
25 (0.545)
21 (0.196)
3 (0.02)
152 (1.951)
9 (0.003)
14 (0.018)
43 (0.068)
56 (0.141)
122 (0.23)
1374 (17.361)
5476
(59.1031)
Species
Puntius brevis
Labiobarbus
leptocheilus
Parachela spp
Total
1458 (17.991)
1428 (17.0886)
1216 (6.6625)
Species
Sub 15
Sub 30
V-Slot
Grand Total
Parambassis siamensis
714 (1.322)
543 (0.525)
55 (0.044)
1312 (1.891)
Rasbora aurotaenia
572 (2.618)
24 (0412)
73 (0.394)
669 (3.424)
Thynnichthys thynnoides
214 (5.297)
74 (1.530)
161 (3.244)
449 (10.071)
Crossocheilus atrilimes
128 (0.473)
113 (0.438)
51 (0.227)
292 (1.138)
Puntius brevis
163 (0.541)
43 (0.228)
26 (0.135)
232 (0.904)
Labiobarbus siamensis
180 (1.400)
16 (0.100)
14 (0.110)
210 (1.610)
Xenentodon sp.
122 (0.907)
35 (0.260)
7 (0.069)
164 (1.236)
Homaloptera smithi
69 (0.017)
36 (0.010)
57 (0.015)
162 (0.042)
Puntioplites falcifer
87 (0.238)
31 (0.054)
4 (0.020)
122 (0.312)
Rasbora daniconius
94 (0.223)
0
1 (0.001)
95 (0.224)
2343 (13.036)
915 (3.557)
Total
449 (4.259) 3707 (20.852)
Fishway at Pak
Peung operation
in rainy season
2013 – required
some
modifications

Cone fishway fully
commissioned in
2014
 Enables
fish to move up
into Pak Peung
Wetland

So far 132 different
species have been
trapped moving
through fishway
into wetland
Experimental weir construction at Nong Teng Fish
Hatchery Station – Pilot Study with ACIAR Funding


‘Release fish upstream and collect downstream
3 treatments
Net
Flow
Weir
Undershot
1) Undershot
configuration
Overshot
2) Overshot
configuration
Weir
3) ‘no weir control (no passage)
Sensorfish release
Data download
Life stage
Scientific name
Common Name
Larvae
Cyprinus carpio
Common carp
Clarius sp.
Pa Douk Catfish
Clarius sp.
Pa Douk Catfish
Pangasius
hypophthalmus
Shark catfish
Oreochromis nilotica
Tilapia
Hypsibarbus sp.
Pa Pak
Juvenile
Haemorrhage
(bleeding)
Eye
damage
Fin damage
Wounds
Wounds and
scale loss
Dead
Overshot
juveniles)
Overshot (of (n=158
158 juveniles
recovered)
Head severed, 5
Head severed, 6
Eye damage, 4
Wounds, 1
Undershot (of 162
juveniles
recovered)
Undershot
(n=162
juveniles)
Eye damage, 7
Dead, 8
Dead, 7
Wounds, 3
Scale loss, 25
Scale loss, 37
Fin damage, 2
Fin damage, 11
Uninjured, 110
Uninjured, 97
1.
2.
3.
4.
5.
Injury and mortality can occur to fish when
passing downstream at weirs
Impact differs between species and life stages
(some species will be unaffected)
Larvae appear more likely to die than juveniles
Juveniles more likely to be injured than die
Injury and death rates can differ between
different weir designs

Undershot weirs may be worse than overshot for
some species and life stage
1.
2.
3.
4.
5.
6.
Design and operation of irrigation infrastructure should
protect most vulnerable species to death and injury
All designs do not perform the same and the benefit of
overshot versus undershot needs to be further
explored.
More information of which species and life stages are
moving downstream through structures
Next step should involve taking experiment to a real
river/regulator site
More replication will give clearer results
Consider internal injuries as well as external.
ACIAR project FIS/2012/100

To return to the Mekong
fish must leave the
wetland through
undershot gates
AIM:
To assist farming communities and management
authorities to adapt irrigation structures in
ways that increase fishery value
1.
2.
3.
Understand the impact of irrigation
infrastructure on the passage of fish from
wetlands and rivers;
Install and assess the effectiveness of a fishfriendly regulator; and
Determine how improved fish passage at
irrigation structures can increase the value of
capture fisheries.
1.
2.
3.
4.
Fish passage surveys to determine what
species, life stages and biomass of fish are
passing through Pak Peung regulator;
Hydraulic surveys of irrigation structures in
the LMB and MDB;
Installation and testing of a fish-friendly
regulator at Pak Peung;
Economic modelling of improvements in
fisheries value resulting from regulator
upgrades.

Capture fish moving out of Pak Peung
wetland


Fyke and larval netting;
Record species, abundance, length and
weight
Fyke nets
Larval nets
Sensor Fish

Sensor Fish will be used to measure hydraulic
stresses (e.g. shear and pressure)faced by fish at
different regulators;
Sensor Fish trial at Pak Peung 2013

‘Fish-friendly’ overshot Layflat gates have
successfully replaced undershot gates at
over 50 sites in Australia;

Will be retro-fitted upstream of existing
gates at Pak Peung

Experiments will test difference in fish
mortality between old undershot and new
layflat gates


Pak Peung will become the first ever
demonstration site for both upstream and
downstream fish passage at a wetland in
the LMB
Important teaching and promotional tool for
application at more sites throughout the
LMB

From fish passage and mortality estimates
we will be able to compare the cost of
upgrading a regulator to the returned value
to the capture fishery
Smart Infrastructure for Mekong Program (SIM)
USAID
Goals:
1. Guide construction of fish-friendly hydroelectric dams including both large and mini hydro.
2. Develop critical criterion necessary to construct fish-friendly hydro using a combination of
laboratory and field based research.
• Determine the relationship between a range of rapid pressure changes and shear forces
representative of turbine passage and damage to Lower Mekong species to develop
threshold criteria.
3. Use Sensor Fish technology to determine the range of pressures that fish could be exposed to
at currently operating hydropower projects.
4. Build the capacity of Lao researchers in the design and implementation of eco-hydraulic
research to promote sustainable downstream fish passage solutions at hydropower dams
• Provide training to Lao researchers in the use of equipment for exposing fish to a range
of rapid decompressions and shear forces that are representative of passage through
hydroturbines.
• Provide training to Lao researchers in the use of Sensor Fish to collect information about
conditions present at current hydropower projects to guide sustainable development of
hydro.
5. Provide a study tour to the key policy makers on fish-friendly hydropower