2. INTRODUCTION
Water covers 71% of the Earth surface.
It is essential for all forms of life.
It plays a vital role in county’s economy.
Agriculture is the major user of water.
Timely and adequate availability of water is required
for the sustainability of Agriculture.
Hydropower is the cheapest way of generating
electicity.
3. WATER RESOURCES
“Sources from which water is available for the water supply
schemes or irrigation is called as water resources.”
The most common resources of water are:
Surface Water
- River flows
- Rainfall
Groundwater
-Useable Groundwater Aquifers
- Useable Layers Overlying Saline Water
4. SURFACE WATER RESOURCES
Water in river,lake or fresh water wetland.
Naturally replenished by precipitation, lost through discharge to the
oceans,evaporation,and subsurface seepage.
Total quantity of water in the system may depends on
Storage capacity
Permability
Runoff
Precipitation and evaporation rate
Human activities
5. RIVER FLOWS
Surface water resources of Pakistan mainly based on :
Flows of indus river and its tributaries (Jhelum,Ravi,Beas,Chenab and Sutlej)
Total length of indus river is 2900 Km.
It brings 148.8 MAF of water annually.
Average annual flows in 3 major river basins of Pakistan is :
RIVER BASIN AVERAGE ANNUAL FLOW
MAF(Million Acre Feet)
Indus Basin 145.0
Mekran Coastal Basin 3.0
Kharan Closed Desert Basin 0.8
6. RAINFALL
70% of annual rainfall occurs in months of June to September.
Mean Annual rainfall ranges between :
125mm in Balochistan to 750mm in Northwest.
Winter rains are generally widespread.
The present contribution of rain to crops in irrigated areas is about 6 MAF.
7. GLACIERS
They are made up of fallen snow that compresses into large ,thickened ice
masses.
The glacier area of Pakistan is about 13,680 sq km.
Important glaciers are
o Siachin (75 km)
o Baltoro (62 km)
o Baifo (67 km)
o Hispar (49 km)
o Batura (57 km)
o Rimo (45 km)
8. GROUNDWATER RESOURCES
Most of groundwater resources of Pakistan exist in indus plain.
It is about 1,600 km long and covers the area of 21 mha.
It is blessesd with unconfined aquifer having potential of 50 MAF.
It is exploited to an extent of 38 MAF by 562,000 private tubewells and
10,000 public tubewells.
Sindh and Balochistan : 40 ft depth
Rachna doab : 100 ft
In Punjab 79%,in Sindh 28% of area is underline by freshwater.
More than 500,000 tubewells supply about 41.6 MAF irrigation water.
9. WATER DISTRIBUTION
For sharing and distribution of surface water 2 important agreements have
been made :
The Indus Water Treaty – 1960 ( International level)
Apportionment of Indus Water Accord – 1991 (National level)
10. THE INDUS WATERS TREATY -1960
Signed between INDIA and PAKISTAN through mediation by WORLD
BANK.
Under the treaty, Pakistan was given away the use of Western Rivers(
Indus, Chenab and Jhelum).
2 Storage dams , 8 Inter-link canals , 6 Barrages was constructed.
The construction of storages and link canals allowed the operation of
Indus irrigation system in controlled and improved manner.
11. CURRENT SITUATION IN PAKISTAN
There are number of key issues relating to the water resources which confront Pakistan
today.
The population of Pakistan is continuously increasing
WATER DEMAND FOR DOMESTIC USE
Year 1990 2000 2025
Population
(Million)
110 140 260
Water
demand(MAF)
1.4 5.2 9.7
12. INDUS BASIN IRRIGATION SYSTEM
It comprises of :
Major reservoirs : 3
Barrages : 16
Head works : 2
Inter-link canals :12
Canal system : 44 (23 in Punjab,14 in Sindh,5 in KPK, 2 in Balochistan)
Water courses : 107,000
Length of canals : 56,073 km
Tube wells : 500,000
13. WATER SCARCITY:
Average canal-water supplies to the indus basin canal commands are around 104 MAF.
Out of this only 38 MAF is available during Rabi season due to which their productivity is
affected.
Key issues related to water availability:
Annual and seasonal variability in availability of surface water.
Reduction in capacity of storage reserviors.
Depleting ground water tables.
Salt water intrusion.
Increase in domestic and industrial demands.
14. INADEQUATE STORAGE AND
SEDIMENTATION
Sedimentation in three major reservoirs –Tarbela, Mangla and chashma- decrease their
storage capacity upto 40%.
Their estimated loss is given in following table :
REDUCTION IN CAPACITIES OF MAJOR RESERVIORS
Reservoi Year
commissione
Live storage
capacity
(MAF)
Decrese
(%)
starting 2
0
0
0
2010 200 2010
Mangla 1967 5.3 4
.
5
4.2 15 21
Tarbela 1974 9.7 8
.
8
7.3 9 25
Chashma 1971 0.7 0
.
3
0.2 57 71
Total 15.7 1 11.7 13 25
15. GROUNDWATER OVER-DRAFT,WATER
LOGGING AND SALINITY
Continued abstraction of groundwater has resulted in overpumping and
lowering of water table.
Over-pumping could be due to low rate of groundwater-use,floods during
summer and mismanagement.
Water logging and salinity emerged due to :
Flat topography
Seepage from unlined canals
Mismanagement of irrigation water
Poor drainage
16. LOW SYSTEM EFFICIENCY AND
PRODUCTIVITY
Large amount of water is lost through seepage and evaporation.
Conveyanvce losses in canals and water courses are around 25% and 30%
respectively.
Application losses in fields are around 25-40%.
Overall irrigation efficiency is hardly 30%.
In Balochistan irrigation to apple orchards exceeds the requirements by
100%.
17. CONCLUSION
Pakistan’s water resources have been diminishing at an alarming rates.
The quality of water is also deteriorating with time.
