Presented by Himadri Samal at Sambalpur unuversity

2. • Sand mining is a practice that is used to extract sand,
mainly through an open pit. However, sand is also mined
from beaches, inland dunes and dredged from ocean beds
and river beds. It is often used in manufacturing as an
abrasive, for example, and it is used to make concrete.
• Sand dredged from the mouths of rivers can also be used to
replace eroded coastline.
• Another reason for sand mining is the extraction of minerals
such as rutile, ilmenite and zircon, which contain the
industrially useful elements titanium and zirconium. These
minerals typically occur combined with ordinary sand.
• Short term benefits

3. • Direct impact on the stream’s physical habitat characteristics
 Channel geometry
 Bed elevation
 Substrate composition and stability
 Instream roughness elements
 Depth
 Velocity
 Turbidity
 Sediment transport
 Stream discharge
 Temperature

4. 1. Alteration of the flow patterns resulting from
modification of the river bed
2. An excess of suspended sediment
3. Damage to riparian vegetation and instream
habitat

5. Potential impacts
of sand mining
Instream habitat
Riparian habitat

6. Figure 2.1: Instream habitat (Left) and Riparian habitat (Right)

7. • Kinds of instream sand mining
 Dry-pit
 Wet pit mining
 Bar skimming or "scalping."
 Pits on the adjacent floodplain or river terraces
• Types of instream habitats
a) Log structures
b) Log jams
c) Cover structures
d) Boulders structures etc.

8. a. Extraction of bed material in excess of natural replenishment by
upstream transport
o This causes bed degradation, increases suspended sediment,
sediment transport, water turbidity and sand/gravel siltation
o Becomes unsuitable for many aquatic organisms
o Gravel removal not only impacts for the extraction site

10. b. Bed degradation, changes themorphology of thechannel
o Potential for diversion of flow through
o Migration blockages for fish during low flows
oIf the gravel extraction activity is conducted away from the active
river channel during low water periods
o As active channels naturally meander, the channel may migrate
into

11. c. Operation of heavy equipmentin thechannelbed
o Can directly destroy spawning habitat for fish and
macroinvertebrate habitat, and produce increased turbidity
and suspended sediment downstream.
Figure 2.2: Turbid water due to sand mining

12. d. Alteringchannel hydraulics
o Stockpiles and overburden in the floodplain can alter channel hydraulics
during high flows.
e. Removalor disturbanceof instreamroughnesselements
o It negatively affects both quality and quantity of instream habitat.
o Instream roughness elements - particularly large woody debris, play a
major role in providing structural integrity to the stream ecosystem.

13. • Many hectares of fertile streamside land are lost annually
• Degraded stream habitats result in lost of fisheries productivity,
biodiversity, and recreational potential.
• Severely degraded channels may reduce land and aesthetic values.
• All species require specific habitat conditions to ensure long-term
survival
• Unstable stream channels are inhospitable to most aquatic species
• The complete removal of vegetation and destruction of the soil
profile destroys

14. A.Destructionofthe riparianzone
It serves as buffer to pollutants entering a stream from runoff, controls
erosion, and provides habitat and nutrient input into the stream.
B. Loweredfloodplaingroundwater
o Riparian vegetation reliant on the groundwater will subsequently be
stressed
C. Permanentflooding
o Subsequently causes annual or frequent flooding into the disturbed site.
D. Destructionof riparianvegetation
o This is caused by heavy equipment, processing plants at or near the
extraction site
E.Disturbingthenaturalhydraulicsoftheriparianzone
o Generation of recruitment may be lost
F. Removaloflargewoodydebrisfromtheriparianzone
o It negatively affects the plant community.
G. Reducedvegetative bankcover
o Resulting in reduced shading and increased water temperatures.

15.  Impacts for groundwater
Bed degradation from instream mining lowers the elevation of stream flow
Saline water may intrude into the fresh water body
 Impacts for Water Quality
Increased riverbed and bank erosion
Increased short-term turbidity
Suspended solids can increase water treatment costs

16. Physical
Water
quality
Ecological

17. • Bed degradation and consequent effects on channel and
bank stability
• Increased sediment loads, decreased water clarity
• Changes in channel morphology and disturbance of
ecologically important roughness elements in the river bed
• Ecological effects on bird nesting, fish migration etc.
• Modification of the riparian zone including bank erosion
• Direct destruction from heavy equipment operation
• Discharges from equipment and refueling
• Impacts on structures and access
• Biosecurity and pest risks
• Impacts on coastal processes

18. Figure 2.4 : Extensive Modification to Stream Channel Caused by sand mining

19. Acid Mine Drainage-Threat to water resources
Acid mine drainage also dissolves toxic metals
such as copper, aluminum, cadmium, arsenic,
lead and mercury from the surrounding rock
Yellow boy
The impacts to aquatic life may range from
immediate fish kills to sub lethal, impact affecting
growth, behavior or ability to reproduce

20. Figure 2.5 : Yellow boy in a streams

21. • 1. Sand mining sites should be situated outside the
active floodplain and excavation should not take place
from below the water table.
• 2. Larger rivers and streams should be used
preferentially than small rivers and streams.
• 3. Pit excavations located on adjacent floodplain or
terraces should be separated from the active channel.
• 4. The removal or disturbance of instream roughness
elements during gravel extraction activities should be
avoided.
• 5. Turbidity levels should be monitored
• 6. Operation and storage of heavy equipment within
riparian habitat should be restricted.

22. Reference
• Wikipedia
• slideshare.com
• iasscore.in
• threeissues.sdsu.e
du