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Main
Drainage Channels for Fanling Sheung Shui and Hinterland
Title of EIA Main Drainage Channels for Fanling, Sheung Shui
and Hinterland
Completion Date October 1997
EIAO Register Office Reference EIA-127/BC
Project Proponent Territory Development Department
Project Description The project is to train the rivers in
the River Indus Basin to alleviate flooding in the basin.
The rivers to be trained under the project include River Sutlej
in Area 30B and Indus Major, Indus Minor and River Beas.
Recommended
environmentally friendly design measures of channels
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a |
Design
of abandoned meander for wetland habitats
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As a result
of river training works, some existing wetland habitats for
wildlife such as Painted Snipes will be affected. Abandoned
meanders along the Indus River and River Beas could provide
an opportunity for re-creating the wetland habitats. The design
features of the meanders (Figures 1, 2
and 3) are as follows :
| i. |
retention
of original river stream course for creating wetland habitats; |
| ii. |
planting
of indigenous vegetation to reprovide a riparian habitat
for wildlife; |
| iii. |
marsh
areas created to provide habitats for water birds and
herbivores; and
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| iv. |
bamboo
planting in some meanders to provide potential nesting
sites for egrets and herons. |
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b.
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Ecological
design features of channels
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Ecological
design features of channels (Figures 3 and
4) are summarised as follows :
| i. |
grasscrete
or reinforced grass lining at side slopes and base of
channels above tidal influence to provide a grassy habitat; |
| ii. |
natural bottom with rip rap stone lining (to provide scour
protection where required) at channels with bed at or
below 0.00m PD to maintain existing aquatic habitats; |
| iii. |
planting
of vegetation along outside slopes of channel embankments
to replace habitats lost and to enhance the diversity
of habitats and their associated fauna in the area; |
| iv. |
reprovision
of weirs to ensure permanent water cover for 70% of the
channel system which provides ponded water and deep water
habitat for aquatic life. |
| v. |
reprovision
of weirs to ensure permanent water cover for 70% of the
channel system which provides ponded water and deep water
habitat for aquatic life. |
(Note : Modified from Figure 5.3 of the Supplementary Paper on Ecological Mitigation Utilising Abandoned Meanders dated
May 1998 prepared by the Maunsell Consultants Asia Ltd)
(Note : Modified from Figure 3.15 of the Final Assessment Report dated October 1997 prepared by the Maunsell Consultants Asia Ltd)
(Note : Modified from Figure 3.12 of the Final Assessment
Report dated October 1997 prepared by the Maunsell Consultants
Asia Ltd)
Figure 4 - Ecological Features of Channel Design
(Note : Modified from Figure 3.10 of the Final Assessment
Report dated October 1997 prepared by the Maunsell Consultants
Asia Ltd)
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