News Update Jan 2001
Plans for the hatchery at Taymouth have now
been suspended. With the possible sale of the
estate on the cards it would be unwise to continue
until new owners are in place. In the mean time
the Board is looking at locations in Killiekrankie.
Hatchery Plans
Salmon fishing is an integral part of the local
tourist industry. The Taymouth and Bolfracks
water has over the last two decades produced
5 year average in excess of 100 salmon and grilse.
In 1997 the total was 75 fish ad this year was
34. This decrease is already impacting fishing
revenues as well as accommodation. It is thought
that this fall is due to floods in 1992 and
1993 washing out redds together with unknown
factors at sea.
The main redds on the water are around the
Kenmore Bridge and in the tail of the Hotel
Pool. This is the first pool in the system and
is thus subject to flooding caused by variations
in the loch height. This pool is also heavily
fished by trout anglers, causing further mortalities
to parr. Below the Hotel pool is approximately
2 kilometers of relatively fast water which
is unsuitable for spawning, but which is ideal
parr habitat. This section is also heavily fished
(600 trout rods and 600 salmon rods per annum)
causing additional mortalities. There are also
redds below the junction of the Tay and the
Lyon. While there are good gravels this confluence
is very susceptible to floods and water-course
changes. There are few remaining burns, most
having been converted to land drains. The adult
salmon caught and not returned also represent
a loss to the system, which should be made good.
The proposed hatchery is intended to act as
an insurance policy against floods and to make
up a short fall in parr caused by mortalities.
Holding fish in the hatchery itself represents
a risk which should be spread. The hatchery
will produce fish for restocking at multiple
stages. The borehole will probably supply water
at 10oC.
Eyed eggs will be available for scattering
after 23 days.
First feed after 44 days.
5 g by approximately August 10g approximately
October
Water Sources
The site has three potential sources of water.
Ground water - requires a new borehole. Surface
water - Existing piped castle supply taken from
Kenmore Hill. Surface water - abstracted water
from the River Tay.
Groundwater
The preferred source for hatchery work is ground
water. Such water is of a know quality and is
pollution free. The new village bore-hole which
is approximately 1 mile further up the valley
has been producing 27 gallons per second of
high quality drinking water for the last month.
The water table has dropped an insignificant
amount during this test. The proposed site also
sits upon alluvial drift. A ground water supply
can thus be made available. Groundwater carries
a slight penalty in that it will be a different
temperature/quality to nature. For ova this
disadvantage is outweighed by its' guaranteed
quality. Its' consistency also allows better
management/forecasting by degree days. Groundwater
supply does not require SEPA licence but will
require testing.
River
The Tay, which has constantly high flows is
less than 100m from the building. An intake
and screens would be required. The very high
flows experienced would mean that the engineering
would need to be a high standard. There would
remain a slight risk from pollution. Since the
water will (in the winter) be close to freezing,
there would be increased risk of freezing within
an unheated hatchery. It is not proposed to
use the river supply initially, but this may
be reviewed at a latter date.
Burn/Castle Supply
The old Castle water supply is piped to the
building. This is hill water, collected by a
system of earth and stone tanks. Many of these
pipes are heavily rusted. Once the Golf club
is closed this supply should be opened up to
flush the pipes and to check their integrity.
The volume available can be checked at the same
time. A sample should also be taken by SEPA
for analysis. Note the lethal level for iron
is 1mg/l. If this supply can be made available
without major works, it would be a valuable
source for fry rearing. It should be warmer
than groundwater and will thus promote growth.
Development of fry would thus be closer to nature.
There may also be an element of early imprinting
of water quality.
The second building which will
be used for the standby generator, borehole
and storage.
Water Quality
How much water is required?
Southern Water recommend 227 litres/day/1000
ova
Huet & Sparsholt suggest 720 litres/day/1000
ova (0.5 l/min/1000)
For fry rearing (up to eight months) Sparsholt
recommend 17280 l/day/1000 fry (6-12 l/min/1000
fry).
To raise 25,000 fry we will need a minimum
of 25x17280=432,000 l/day (300 l/minute) For
future expansion and to dilute "pollution" it
is suggested that the water capacity be set
at 600 l/minute from the outset.
The building has an estimated ultimate capacity
of 250,000 ova and 120,000 fry, which would
use 1,500 l/ minute. This figure should be borne
in mind during construction. Water is running
at 10oC with no water quality problems. As with
any groundwater supply it will be supersaturated
with nitrogen and will be low in oxygen. A degassing
tower will therefore be required. This will
not only remove nitrogen but will ensure 100%
oxygen saturation. This should ensure that no
further oxygenation is required. In case of
emergency a bottled O2 supply will be installed.
Bottles will be held in the dry area. A pipe
network will run down the west face with connectors
set at shoulder level on each pillar of the
rearing area.
Water Disposal
There should be little change to water quality
from hatchery work. There is no suspended solid
and even at outlet there will be good oxygenation.
Since the fry to be raised will rarely exceed
10g in size there will no significant suspended
solid output. Ideally the water should be disposed
of in a soak-away. Thus making the site a closed
system and ensuring that there is no risk of
disease transfer. There is an existing soak-away
to the rear of the building. The total capacity
of this soak-away is currently unknown. A short
test was conducted with the fire engine. The
soak-away took 500 gallons in less than 3 minutes.
A second test was run for a period of 2 hours
pumping at approximately 200 gallons per minute.
The soak-away absorbed this amount with no evidence
of back-flushing at the end of the test. This
suggests that it is suitable for our purposes.
There is also potential for an overflow running
from this soak-away to a deep drain running
to the river with an out-fall on the Castle
pool by land-drain. This pipe network is in
good condition in-spite of its age. It needs
a good clean as there is some siltation. Several
manhole covers are in need of replacement. There
is an existing silt trap before the soak-away.
This will be adequate for filtering hatchery
water as there is little or no sediment. A new
sediment chamber will be installed between the
rearing area and the existing sediment trap
(final polish). Lattest
news - SEPA have asked that a settlement
pond be provided as part of the discharge consent.
Discharge will then be made to the river rather
than to the soakaway.
Rearing
From the rearing area waste water will be sent
to the "Sump" area. This is a 2.2m x 3m room
which lies slightly below the main area. It
is estimated that the excreta produced by 25,000
15g fry will be less than 2kg per day. At maximum
capacity this would increase to 20kg per day.
SEPA might allow a direct discharge of this
waste into the Tay. Note that there should be
no risk of disease from the site, which accept
only gamete (adult fish will be stripped offsite).
Nevertheless we wish to avoid any risk and would
only consider direct discharge under exceptional
circumtances (a major flood could theortetically
bring the soak-away to capacity). As a last
resort discharge water could be sent through
a swirl concentrator in the "Sump" area with
foul water being routed to the existing Castle
sewerage network (garage flats).
Power
There is an existing three-phase supply approximately
20m from the buildings. Three phase power should
be delivered to the Dry room (control box and
standby generator). Single phase should be delivered
to the building. Main building Hatchery no power
outlet Rearing Area Deliver via 4 way overhead
"waterproof" gangs located on steel roof beams
(away from water). Initially only 2 gangs are
required on the beam close to the hatchery.
Additional gangs will be placed on the 3 remaining
girders.
Dry Area
4 power outlets at waist height. Single phase
control box and circuit breakers. Three-phase
control box. Three-phase delivered to submersible
pump. A standby generator (three phase) on automatic
cut-over. Lighting Hatchery 2 overhead light
sockets (up to 150 watt) with pull down switch
(away from water) Rearing Area 2 overhead light
sockets per steel girder (total 8) probably
40w. Light switch by internal door to Area Dry
Area 2 overhead light sockets, switch by main
door.
Sump Area
2 overhead light sockets, switch by entry door
(waterproof). Telephone A telephone cable runs
down the side of the building. Telephone connection
should be made to the Dry area. This will be
used for alarms. The header tank level and oxygen
level should be alarmed. Mortalities To eye
5% Hatch 5% Alevin 2% Fry 10% (After 12 months)
Disease
The site will only ever receive gamete, so
there is little risk of incoming disease. The
whole building will be shut down in October
for cleaning.
Planning Permissions
Permission will be required - at a minimum
as change of use to agricultural and has been
applied for. There will be few external changes.
Ideally the chimney and stairs to the rear of
the building should be removed (these are causing
damp to get into the structure). Two windows
and 2 doors should be bricked up. Lattest
news - Planning Permission has now been
received,
Future Expansion
Water quantity and discharge capacity are the
most significant limitations. Water volume is
unknown, but expected to be more than enough
for future expansion. Discharge capacity could
be increased by putting in a new 50m pipe to
the river. Space is the next most important
constraint. The Hatchery could probably handle
up to 250,000 eggs while inside the rearing
area could probably handle 120,000 fry. This
could be further expanded to the outside of
the building (when risk of freezing is remote)
There are existing concrete slabs with adjacent
drainage.
Funding
Taymouth Castle Estate has agreed to fund operating
costs. The Tay Salmon Fisheries Board have agreed
to supply a small amount of capital and it is
hoped that The Tay Foundation will also assist.
Lattest news - A formal request
to the Foundation has now been made. It still
means that we have to raise some £35,000.
Being in the headwaters the hatchery will benefit
owners and anglers right down to the estuary.
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