Pre-construction/Construction Phase
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1
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Land Use
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Road alignment may pass through cultivated and forested land resulting in a permanent loss of the resources.
While the landowner has to part away with his land ownership, the environmental effects can amplify if proper operation and maintenance schedules are overruled.
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Plan infrastructure such as road alignment to minimize loss of resources.
Avoid width of infrastructure such as road of more than 4.5 m in hilly area.
Demarcate RoW to avoid encroachment.
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2
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Material Use
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Excess extraction of local resources, such as wood, sand, soil, boulders, etc.
Degradation of forests, erosion and landslide at steep locales due to boulder, stone extraction.
Change in river/stream ecosystem due to unchecked sand extraction.
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Extract materials only on need basis.
Avoid sensitive areas, such as steep slopes and water-ways.
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3
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Slope Stability
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Extraction of forest products and cutting of trees in the steep slopes increases soil erosion/landslide due to loss of soil binding materials.
Wrong alignment can trigger slope failure
Haphazard disposal of construction waste can disturb slopes
Improper drainage facilities can result in erosion and landslides
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Extract carefully and secure the top soil within 25 cm from the surface.
Limit down grading of the infrastructure such as road to 50.
If down grading exceeds 70, construction of side drainage is necessary.
Keep optimum balance in extraction and filling of soil works.
geo-hazardous assessment and mapping
Use designated disposal site and avoid sidecasting of spoil
Provide proper drainage
Use bio-engineering on exposed slopes
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4
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Wildlife
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Wildlife habitats at forests, shrub land along infrastructure such as road alignment are affected from the infrastructure such as road construction activities.
Wildlife and human conflicts increase as wildlife might destroy the crops or attack the construction worker.
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Avoid as much as possible areas with high biodiversity.
Efficient movement of machinery and other traffic.
Control poaching activities and regulate movement of labor force and their dependents into the forest area.
District Forest Office and its subsidiary body should be involved in monitoring the activities of the construction workers and officials to minimize wildlife harassing, trapping and poaching.
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5
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Drainage
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Higher flow rate of surface water and water logging induce land slides, erosion.
Quality of infrastructure such as road diminishes due to poor drainage such as water logging, immense flow rate of surface water.
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It is strongly recommended that the cross drainage outlets must be channeled to the confirmed natural drains.
If horizontal slope exceeds 5%, construction of flow control device necessary every 20m.
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6
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Protection of Vegetation
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Protected areas and highly forested areas.
Degradation of forest areas.
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Degradation of agricultural land.
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Use minimum and efficient use of wood products for construction.
Initiate plantation at damaged and damage prone areas.
Increase liability of local forest user groups.
Avoid protected areas or densely forested areas
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7
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Disposal of Construction Wastes
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Dumping of wastes along the infrastructure such as road or elsewhere.
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Selected spoil dumping sites should be used.
After disposal, the area should be leveled and compacted.
It is recommended to conserve the soil by planting indigenous plants including grasses.
Wastes could also be used as leveling materials along the infrastructure such as roadside.
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8
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Disposal of Sanitary Wastes
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Unmanaged sanitary waste disposal creating health problems and public nuisance.
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Proper sanitation area needs to be demarked.
Check for hygiene of work force.
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9
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Impacts on amenities along RoW
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Infrastructure such as road crossings at water supply, irrigation lines may be disturbed/damaged.
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Avoid as much as possible the crossing over such amenities.
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10
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Pollution
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Dust generation from construction activities, construction vehicular movement increases air pollution.
Noise pollution likely from construction machinery operation and vehicular movement.
Sanitary problems likely at the construction and workforce quarters.
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Possibly construction period should be during August to December when soil moisture content is most.
Consider construction of infrastructure such as road at 50 m from settlement.
Enforce speed limit of vehicles and construct the infrastructure such as road according to volume and size of traffic movement.
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Operation Phase
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1
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Encroachment
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Unmanaged settlement, construction along the RoW.
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Establish RoW properly and enforce its limits.
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2
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Interruption of Water Flow along RoW
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Concentrated flow left unattended might have severe impact at the downhill alignment of the infrastructure such as road.
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Cross drain structures, namely pipe culverts, slab culverts, box culverts, need to be maintained.
Outlet of these structures would be carrying the concentrated run off flow of the respective catchment, which will be quite high during rainy season, which in turn would require proper planning of drainage systems.
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3
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Pollution/Vehicular Emission
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Dust generation from vehicular movement increases air pollution.
Noise pollution likely from vehicular movement.
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Enforce speed limit of vehicles.
Maintain traffic size movement.
Discourage use of horns.
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4
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Aesthetics
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Infrastructure such as road construction is likely to increase landscape scars along the infrastructure such as road alignment.
In addition if the construction spoils are disposed off improperly, the ground vegetation would be destroyed which will be visible from a distance.
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Such damage cannot be avoided but can be minimized through re-plantation of indigenous species and greenery development.
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