5.1
Management Regime Stages and
Programme
5.1.1
Management
actions and frequencies will be vary according to the following stages:
·
within
the preworks period / construction phase;
·
during
an establishment period of 24 months from completion of planting; and
·
during
operation of the fishponds and marshland mitigation areas.
5.1.2
The
contractor will be responsible for the management regime until the completion
of the establishment period, at which point the site will become the
responsibility of KCRC or its designated successor.
5.1.3
A
comprehensive revised Operational Management Programme with detailed
specifications and timings for actions for each unit will need to be produced
within the last three-months of the establishment period. The implementation of
this programme will then start immediately after the completion of the
establishment phase and will be the responsibility of KCRC or its designated
successor. The Operational Management Programme will take into account any
modifications that were found to be necessary in the design and establishment methods
used for creating the habitats, the degree of success in establishing the
habitats and any changes in the factors affecting them. Management actions will
also need to respond appropriately to the outcome of monitoring where it is
found that Action Levels and Limits as defined in Section 6 are exceeded.
5.1.4
The
Operational Management Programme should be regarded as a working document and
reviewed annually, so that proposed actions are modified according to progress,
monitoring results and other relevant events. The Operational Management
Programme should be thoroughly revised every five years. The five-year revision
should include a through analysis of all monitoring data and a review of the
vegetation mix, with an identification of areas to be cleared and replanted.
5.2.1
A
list of broad management actions that must be undertaken for the fish pond area
and the marshland areas are provided in Tables 5.1 to 5.3. Timings for the
actions will be added when an Environmental Permit has been given and a works
timetable established.
5.2.2
Establishment
management actions should be reviewed after the first year. Frequencies and
timings for the ongoing operation stage are indicative, as these will be
specified as part of the development of the detailed Operational Management
Programme. Further details of some key management actions are provided below.
5.2.3
The
tables do not include supporting administrative actions as these will depend on
future contracting arrangements and responsibilities for implementation of the
Operational Management Plan. Long-term actions.
Fish Pond Management
5.2.4
As
described in the EIA Report (BBV 2000) the majority of the target species of
conservation occurring within the Wetland Conservation Area and vicinity of the
San Tin Lok Ma Chau station benefit from the continuation of traditional fish
farming activities. The enhancement of the fish ponds within the mitigation
area will therefore include the continuation of active traditional fish farming
management in each on most of them.
5.2.5
The
main management enhancement of the ponds will be to regulate and extend the
period of draw-down for harvesting. Under current fish-farming practices
harvesting is carried out in winter by reducing the water depth of the pond (by
pumping water to another pond for storage) and the gradual netting of the stock
over a couple of weeks. This winter draw down may occur only once every three
to five years depending on the commercial situation. However, the precise dates
of harvesting are dependent on market prices and this can result in
food-resource ‘bottle-necks’ if no or few ponds are drained at any one time.
Draw down of the ponds will therefore be carried out on a regular basis, and
more frequently than currently practiced,
irrespective of the market value of fish as indicated in below.
5.2.6
Draw-down
periods will also be for a fixed time of 20 days. This is longer than normal
and will thus further increase feeding opportunities thereby further reducing
potential feeding bottle-necks.
5.2.7
It
is also proposed that at any one time approximately 25% of the fish pond area
will be taken out of production (on a rotational basis) for two seasons (see
below for details). This will provide a number of more natural 'lake' like
habitats thereby increasing habitat diversity within the area. It is expected
that such habitats will be used by targets species such as herons and egrets,
and will be particularly valuable habitats for ducks and non-bird taxa that are
susceptible to the highly eutrophic conditions in managed fish ponds. Recent
conversion of some fishponds to similar freshwater habitats within the Mai Po
Nature Reserve have produced highly valuable habitats which hold large numbers
of wintering waterfowl.
5.2.8
The
operating water levels for each pond are indicated in Table 5.1 below. Initial
Operating Levels (IOLs) are intended levels for ponds when filled/refilled
during the winter after drain-down or harvesting. Maximum Operating Levels
(MOLs) indicate the level above which water must be removed from the pond by
sluice drainage or pumping (off-site or to other ponds as appropriate). Low
Operating Levels (LOLs) are water level ranges, which must be maintained when
ponds are set-aside from production.
5.2.9
If
water levels exceed target levels, then water will be pumped to a storage pond
or disposed of. Decisions on the use of excess water will be made by the Site
Conservation Manager in consultation with an ecologist according to site
conditions and requirements at the time.
Table 5.1
Operating water levels for ponds (m PD)
|
Pond |
Approx existing base level |
Initial Operating Level |
Max Operating Level |
Low Operating Level |
Notes |
|
1 |
0.5
|
- |
1.0 |
- |
These
will be drained and then rain filled to max Level. Max water level to be
maintained by drop board sluice draining to water course |
|
2 |
-0.1 |
- |
0.75 |
- |
These
will be drained and then rain filled to max Level. Max water level to be
maintained by drop board sluice draining to water course |
|
3a |
0.4 |
2.4 |
2.7 |
0.6
– 0.8 |
Ponds
to be joined |
|
3b |
0.5 |
||||
|
4 |
1.0 |
2.3 |
2.5 |
1.1
– 1.3 |
|
|
5 |
0.8 |
- |
1.3 |
- |
This
will be drained and then rain filled to max Level. Max water level to be
maintained by drop board sluice draining to water course |
|
6a |
0.5 |
2.0 |
2.3 |
0.8
– 1.0 |
Ponds
to be joined. Reduce separating bund to level profile as for 3a/3b bund. |
|
6b |
0.7 |
||||
|
7 |
1.0 |
2.0 |
2.3 |
1.1
– 1.3 |
|
|
8a |
0.7 |
2.4 |
2.6 |
0.8
– 1.0 |
Ponds
to be joined |
|
8b |
0.6 |
||||
|
9a |
0.7 |
2.3 |
2.5 |
0.9
– 1.1 |
Ponds
to be joined |
|
9b |
0.8 |
||||
|
10a |
1.0 |
2.4 |
2.6 |
1.1
– 1.3 |
Ponds
to be joined |
|
10b |
0.8 |
||||
|
11 |
0.8 |
2.0 |
2.2 |
0.9
– 1.1 |
|
|
12 |
1.1 |
- |
2.0 |
- |
This
will be drained and then rain filled to max Level. Max water level to be
maintained by drop board sluice draining to water course |
|
13a |
0.7 |
2.0 |
2.3 |
0.8
– 1.0 |
Ponds
to be joined |
|
13b |
0.4 |
||||
|
14a |
1.0 |
2.3 |
2.5 |
1.0
– 1.2 |
Ponds
to be joined |
|
14b |
0.5 |
||||
|
15 |
0.5 |
2.4 |
2.7 |
0.6
– 0.8 |
|
5.2.10
Water
levels will be ascertained according to a gauge board to be placed by the
Contractor in each pond.
5.2.11
Water
levels will be monitored by the Contractor at least weekly from the start of
the trial, or within one day of heavy rainfall events (i.e. > 100 mm of rain
in the NW Territories over 24hours). Water levels will be returned to target
levels within 36 hours of recording excess levels.
5.2.12
During
the preworks period Ponds 1 and 2 will be part drained to specified depth (to
be decided upon at the time depending on the time of year) and then maintained
below 50 cm depth at this level during the preworks period by pumping as
necessary.
5.2.13
A
maintenance programme for other ponds over the pre-works period and during
Phase I mitigation works (i.e. eastern ponds) will be added to the HCMP at a
later date when the detailed construction programme is known.
5.2.14
The
long-term management programme for the fish ponds (other than for Ponds 1,2, 5
and 12, which will be managed according to the regime for the marsh area) will
be a rotational system of fish pond management and set-aside (i.e. shallow
water with no fish production). This is further described below in Table 5.2.
5.2.15
The
sequence of use of each pond starts in January of each year (with stocking) and
is based on the assumption that all ponds have been joined where intended (see
Table 5.1) and all water control structures have been installed together with
the arterial water supply piping.
5.2.16
The
sequence of drain-down, harvesting and refilling for each set of ponds is not
of critical conservation management importance. This can therefore be carried
out as required to reduce pumping and water loss from the system.
5.2.17
When
ponds are drained down for harvesting, water levels must be maintained at or
below Low Level Operating levels for at least 20 days. No more than two ponds
may be drained-down for harvesting at any one time.
5.2.18
After
year 3 it is likely that the sequence will be repeated, but modifications may
be made as a result of lessons learnt from the monitoring of use of the ponds
by target Species of Conservation Concern and their prey populations.
Table 5.2a
Year 1 Pond Use
See Table 5.1 for Initial
Operating Levels (LOLs), Maximum Operating Levels (MOLs) and Low Operating
Level (LOLs)
|
Pond |
Use |
Prescription |
Notes |
|
3 |
Set-aside |
Maintain within LOL
limits. Empty and allow to dry for 30 days between 1 October and 15 December. |
Add water from
reservoir if necessary |
|
4 |
Fish production |
Stock between 1 January
and 1 March. Drain down to LOL
for at least 20 days and harvest 1 November – 14 February (Year 2). |
|
|
6 |
Set-aside |
Maintain within LOL
limits. Empty and allow to dry for 30 days between 1 October and 15 December. |
Add water from
reservoir if necessary |
|
7 |
Fish production |
Stock between 1 January
and 1 March. Drain down to LOL
for at least 20 days and harvest 1 November – 14 February (Year 2). |
Fish production |
|
8 |
Fish production |
Stock between 1 January
and 1 March. Drain down to LOL
for at least 20 days and harvest 1 November – 14 February (Year 2). |
|
|
9 |
Set-aside |
Maintain within LOL
limits. Empty and allow to dry for 30 days between 1 October and 15 December.
|
Add water from
reservoir if necessary |
|
10 |
Reservoir |
Maintain water levels
up to Max Level through year. |
Use as storage pond
and for maintaining target levels in other ponds if necessary |
|
11 |
Fish production |
Stock between 1 January
and 1 March. Drain down to LOL
for at least 20 days and harvest 1 November – 14 February (Year 2). |
Fish production |
|
13 |
Fish production |
Stock between 1 January
and 1 March. Drain down to LOL
for at least 20 days and harvest 1 November – 14 February (Year 2). |
|
|
14 |
Fish production |
Stock between 1 January
and 1 March. Drain down to LOL
for at least 20 days and harvest 1 November – 14 February (Year 2). |
Fish production |
|
15 |
Fish production |
Stock between 1 January
and 1 March. Drain down to LOL
for at least 20 days and harvest 1 November – 14 February (Year 2). |
|
Table 5.2b
Year 2
|
Pond |
Use |
Prescription |
Notes |
|
3 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year3). |
After harvesting and 20 day LOL period |
|
4 |
Set-aside |
Maintain within LOL limits. Empty and
allow to dry for 30 days between 1 October and 15 December. |
Add water from reservoir if necessary |
|
6 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year3). |
After harvesting and 20 day LOL period |
|
7 |
Set-aside |
Maintain within LOL limits. Empty and
allow to dry for 30 days between 1 October and 15 December. |
Add water from reservoir if necessary |
|
8 |
Set-aside |
Maintain within LOL limits. Empty and
allow to dry for 30 days between 1 October and 15 December. |
Add water from reservoir if necessary |
|
9 |
Reservoir |
Maintain water levels up to Max Level
through year. |
Use as storage pond and for maintaining
target levels in other ponds if necessary |
|
10 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year3). |
After harvesting and 20 day LOL period |
|
11 |
Set-aside |
Maintain within LOL limits. Empty and
allow to dry for 30 days between 1 October and 15 December. |
Add water from reservoir if necessary |
|
13 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year3). |
After harvesting and 20 day LOL period |
|
14 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year 3). |
After harvesting and 20 day LOL period |
|
15 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year3). |
After harvesting and 20 day LOL period |
Table 5.2c
Year 3
|
Pond |
Use |
Prescription |
Notes |
|
3 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year4). |
After harvesting and 20 day LOL period |
|
4 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year 4). |
After harvesting and 20 day LOL period |
|
6 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year4). |
After harvesting and 20 day LOL period |
|
7 |
Reservoir |
Maintain water levels up to Max Level
through year. |
Use as storage pond and for maintaining
target levels in other ponds if necessary |
|
8 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year 4). |
After harvesting and 20 day LOL period |
|
9 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year4). |
After harvesting and 20 day LOL period |
|
10 |
Set-aside |
Maintain within LOL limits. Empty and
allow to dry for 30 days between 1 October and 15 December. |
Add water from reservoir if necessary |
|
11 |
Fish production |
Refill to IOL and then maintain below
MOL. Stock between 1 January and 1 March. Drain down to LOL for at least 20 days and harvest 1
November – 14 February (Year4). |
After harvesting and 20 day LOL period |
|
13 |
Set-aside |
Maintain within LOL limits. Empty and
allow to dry for 30 days between 1 October and 15 December. |
Add water from reservoir if necessary |
|
14 |
Set-aside |
Maintain within LOL limits. Empty and
allow to dry for 30 days between 1 October and 15 December. |
Add water from reservoir if necessary |
|
15 |
Set-aside |
Maintain within LOL limits. Empty and
allow to dry for 30 days between 1 October and 15 December. |
Add water from reservoir if necessary |
5.2.19
The
fish pond operations will be carried out by an appointed contractor/s under the
supervision of a Site Manager and an appropriately qualified wetland/fisheries
ecologist. Actions are described in Appendix 3.7.
Other
Management Actions
5.2.20
Other
management actions to be taken over the mitigation area are outlined in Table
5.3.
Table 5.3
General management actions for the Lok Ma Chau mitigation area
|
|
Action |
Construction Phase |
Establishment Phase |
Operational phase |
Notes |
|
|
Water
Control |
|
|
|
|
|
W1 |
Measure
water levels and adjust sluice heights or pump accordingly to meet target
levels (see Appendix 2.1) |
Inspect and
adjust as necessary every 48 hrs (April – September) every week at other
times |
Inspect and
adjust as necessary every 48 hrs (April – September) every week at other
times |
Inspect and
adjust as necessary every 48 hrs (April – September) every week at other
times |
|
|
W2 |
Measure
water quality to cover most critical concerns for short term management (pH,
BOD, salinity) |
Weekly |
Monthly |
Monthly |
In addition
to EM&A requirements (see Table 6.1). |
|
W3 |
Inspect
condition of water control structures and water courses and repair / maintain
as necessary |
Monthly |
Monthly |
Monthly |
|
|
W4 |
Inspect
condition of pumps and water supply structures and repair / maintain as
necessary |
Every six
months at start of wet and dry season |
Every six
months at start of wet and dry season |
Every six
months at start of wet and dry season |
|
|
W5 |
Clear
catchpits / sluices |
Weekly |
Weekly |
Weekly |
Also after
flooding / heavy rainfall |
|
W6 |
Remove
sediment by jetty |
As required |
As required |
When Action
Level exceeded |
|
|
|
Structural maintenance |
|
|
|
|
|
S1 |
Inspect
condition of paths / bunds and repair / maintain as necessary |
Every 6
months |
Every 6
months |
Weekly |
Also after
any flood events |
|
S2 |
Inspect
condition of bunds and repair /
maintain as necessary |
Weekly |
Weekly |
Weekly |
Also after
any flood events |
|
|
Vegetation management |
|
|
|
|
|
V1 |
Replacement
of dead or poorly growing plant material |
Weekly |
According
to direction of the RE or his representative on the advice of the project
ecologist |
When Action
Level exceeded |
Carry out
during the late dry season / early wet season (February – May) |
|
V2 |
Removal / substitution of exotic / undesirable
invasive plants (weeding) |
Weekly |
Removal or
substitution according to direction of the RE or his representative on the
advice of the project ecologist |
Removal
when Action Level exceeded |
|
|
V3 |
Pest control |
According
to direction of the RE or his representative on the advice of the project
ecologist |
According
to direction of the RE or his representative on the advice of the project
ecologist |
Not reqd |
According
to methods approved by the Site Conservation Manager |
|
V4 |
Selective cutting or pruning and removal |
According
to direction of the RE or his representative on the advice of the project
ecologist |
According
to direction of the RE or his representative on the advice of the project
ecologist |
According
to direction of the Site Conservation Manager |
|
|
V9 |
Ditch
clearance |
Not reqd |
Not reqd |
Remove all
reed rhizomes from 25% of ditch length annually |
Remove by
hand in 3 m sections on alternating banks |
|
|
Other actions |
|
|
|
|
|
O1 |
Inspect for
dumping / rubbish and remove |
On all
visits |
On all
visits |
On all
visits |
Consult
management team regarding water pollution or toxic materials |
|
O2 |
Inspect
maintain signs |
Monthly |
Monthly |
Monthly |
|
5.2.21
Water
levels will be adjusted within the marshland according to year to year site
conditions and ecological requirements for target species. These target water
levels will be set by a suitably qualified ecologist within the site management
team after inspection of the site and water monitoring data.
5.2.22
Water
levels may be allowed to drop to below ground level to allow access for
maintenance when necessary.
5.2.23
In
addition to the management of the fish farming system, some management of the
bund vegetation will also be undertaken. This will mainly involve the control
of tall vegetation such as reeds. Although some patches of reed should be
encouraged to develop for cover and screening purposes these must be controlled
as ponds that are enclosed by tall vegetation tend to be avoided by many of the
larger herons and egrets.
5.2.24
Management
will also be carried out of undesirable invasive weeds if necessary.
5.2.25
Vegetation
shall only be removed by cutting and removal of roots / rhizomes by hand or
machine (e.g. backhoe). The use of herbicides will not be allowed, unless
deemed to be necessary (e.g. for treating some invasive species) by the Site
Manager in consultation with an appropriately qualified ecologist.
5.2.26
All
vegetation and associated soils removed from each pond will be disposed of
off-site in an appropriate manner.