Water Storage, Losses And Developing underground Water Usman Chopra Usman Chopra 2008-ag ag-1916 Agronomy 7th Agronomy 7th

Contents Water Storage “The Phenomenon”? Water Storage “The Phenomenon”? Importance Importance Losses “Agriculture Point Of View” Losses “Agriculture Point Of View” Management Management Underground Water Underground Water Projects Projects

Water Storage “The Phenomenon” Surface water and groundwater are stored in a number of ways to supply agriculture, industry and urban users. Some of these storages include: Surface water and groundwater are stored in a number of ways to supply agriculture, industry and urban users. Some of these storages include: large dams (generally constructed by a government water authority or large industry) large dams (generally constructed by a government water authority or large industry) farm dams farm dams aquifer storage (use of an underground aquifer as a storage mechanism for water). aquifer storage (use of an underground aquifer as a storage mechanism for water).

Importance Halving the proportion of people without access to safe drinking water by 2015 is a UN Millennium Development Goal. But equally important are issues of agricultural water management and multilateral water treaties. Halving the proportion of people without access to safe drinking water by 2015 is a UN Millennium Development Goal. But equally important are issues of agricultural water management and multilateral water treaties. Groundwater storage can improve water security and help poor communities adapt to climate change. Groundwater storage can improve water security and help poor communities adapt to climate change. Population could keep climbing — and we must be prepared water is probably the most necessary element for human life, with the exception of oxygen.

Importance Pakistan’s agriculture rely heavily on irrigation. Agriculture is the main player of the economy of Pakistan with 21% contribution to GDP and more than 45% contribution in labour force Pakistan has the world’s largest contiguous irrigation system Pakistan ranks 4th in the world as for as irrigated area ( About 7%) is concerned. About 36 MA( About 75% of the cultivated area) in Pakistan is irrigated land. Pakistan has invested heavily in the irrigation sector. Allocated about $ 8 billion in this sector upto the year

Sources Rainfall Annual rainfall (125mm in South-East to 750mm North-West) Total water generated by rainfall is around 32 BCM 32 BCM Contribution to crops is 10-20% Contribution to crops is 10-20%Groundwater Exploitation of Groundwater is 59 BCM Over 9,00,000 private tube wells 40% of total supply at farm-gate Surface Water Total Inflow is 171 BCM Tarbela (10.38 BCM ft), Mangla (5.90 BCM ft) 48 Canals (61000 km), 19 Barrages 1,70,000 Watercourses (1.6 Million km)

8 Resources o 5 Rivers o 3 Large Dams & 85 Small Dams o 19 Barrages o 12 Link Canals o 0.7 Million Tube Wells o US$ 300 billion Of Investment

Where We Stand In World? The storage capacity of Colorado is 497%. The storage capacity of Colorado is 497%. The storage capacity of Egypt 347%. The storage capacity of Egypt 347%. And the India stores 33% of its water. And the India stores 33% of its water. While pakistan has just 9%storage capacity. While pakistan has just 9%storage capacity.

(a) Terbela dam reservoir World’s largest earth and rock filled dam was built at Terbela on river Indus in 1976 with a gross capacity of maf. World’s largest earth and rock filled dam was built at Terbela on river Indus in 1976 with a gross capacity of maf. live storage capacity 9.68 maf. live storage capacity 9.68 maf. Due to silting, 24.6% of the storage has been lost and now it has a live storage of maf. Due to silting, 24.6% of the storage has been lost and now it has a live storage of maf.

(b) Mangla dam reservoir Mangla reservoir is the second major storage of Pakistan. Mangla reservoir is the second major storage of Pakistan. Built in 1967 on river Jhelum Built in 1967 on river Jhelum Gross capacity of maf and live storage of 5.41 maf. Gross capacity of maf and live storage of 5.41 maf. siltation has lost 13.2% of its storage and presently can store maf of water. siltation has lost 13.2% of its storage and presently can store maf of water.

(c) Chashma barrage reservoir Chashma barrage situated on river Indus built in 1972 Chashma barrage situated on river Indus built in 1972 storage of maf and live storage of maf. storage of maf and live storage of maf. storage capacity reduced by 39.3% and is left with a storage capacity of maf. storage capacity reduced by 39.3% and is left with a storage capacity of maf.

Flow of Rivers The Average annual runoff of our rivers is 142MAF. The Average annual runoff of our rivers is 142MAF. That’s the Minimum recorded so far as low as 97MAF. That’s the Minimum recorded so far as low as 97MAF. And maximum recorded as 172MAF And maximum recorded as 172MAF Annual diversion at the barrages for irrigation purposes is about 104MAF. Annual diversion at the barrages for irrigation purposes is about 104MAF.

Location Delivery at Head (MAF)Loss % age MAF Main and Branch Canals Disty. And Minors 9087 Watercourses Fields Crop Use 41 Total6265  The additional irrigation water requirement at farm gate has been estimated at MAF, which is MAF at canal head (PWSS 2002). Which we can save even if we save water at water course level 30%

PAKISTAN WATER BUDGET - SHRINKING WATER RESOURCES

Freshwater availability scenario (Per person) Freshwater availability scenario (Per person)

YearPopulation Water availability (Million) per capita (m 3 ) (Million) per capita (m 3 )

Major Concerns/Problems A : Problems from management perspective Overall water scarcity, low water availability during winter and at the beginning and end of summer with limited reservoir capacity. Overall water scarcity, low water availability during winter and at the beginning and end of summer with limited reservoir capacity. o Low efficiency in delivery and use. o Inequitable water distribution. o Inadequate operation and maintenance of the system o Excess seepage and wastage in the system. o Administrative and financial constraints.

B- Problems from Farmer’s Perspective o Unreliable and inequitable distribution of irrigation water. o Deterioration of the canal system and frequent breaches due to weak bands. o Increased cases of water theft and failure of management to check them. o Increase in water disputes and delay in actions and justice. o Political interference in system management. o Increasing cost of groundwater extraction

C- Problems From Society’s Perspective C- Problems From Society’s Perspective o Overall poor performance of Government agency managed irrigation system. o Wastage of water and low water use efficiency. o The failure of government to finance, recovery from farmers and high cost of management. o Financial mis-management and poor accountability. o Lack of farmers participation in decision making. o Political influence in management of irrigation water delivery system.

Managerial Better irrigation scheduling Improving canal operations for timely deliveries Applying water when most crucial to a crops yield Water-conserving tillage and field operation methods Better maintenance of canal, watercourses and equipment Recycling drainage water

Institutional Establishing water users organizations for better management of water Fostering rural infrastructure for private sector dissemination of efficient technologies Better training and extension efforts

Recent Projects Recent Projects Mangla Dam Raising Project Billions, 30 ft. The Greater Thal Canal Project Billions, 1.5 MA. Katchi Canal Project Billions,.71 MA. Diamer Bhasha Dam. 18 oct m 12 Billions 4500 MW Rainee Canal – Sindh Chasma Right Bank Canal (CRBC) - KPK Construction of Large and Small Dams Construction of Large and Small Dams Construction of New Canal Systems Construction of New Canal Systems

Methods Of Development Ground water aquifers can be develop by various kinds of structures to ensure percolation of rainwater in the ground instead of draining away from the surface. Commonly used methods are:- a) Developing of bore wells a) Developing of bore wells b) Developing of dug wells. c) Developing pits c) Developing pits d) Develop Trenches e) Soak ways or Recharge Shafts e) Soak ways or Recharge Shafts f) Percolation Tanks

Developing Of Wells Rainwater collected from rooftop of the building is diverted through drain pipes to filtration tank. After settlement filtered water is diverted to bore wells to recharge deep aquifers. Optimum capacity of filtration tank can be designed on the basis of :- Optimum capacity of filtration tank can be designed on the basis of :-  Area of catchement  Intensity of rainfall

Developing Of Pits Recharge pits are small pits of any shape rectangular, square or circular, contracted with brick. The capacity of the pit designed on the basis of :-  Catchments area  Rainfall intensity  Recharge rate of soil.

Developing Of Dug Wells Dug well can be used as recharge structure. Rainwater from the rooftop is diverted to dug wells after passing it through filtration bed.

Develop Trenches Development of trench is provided where upper impervious layer of soil is shallow.This method is suitable for small houses, playgrounds, parks and roadside drains. The recharge trench can be of size  0.50 to 1.0 m wide  1.0 to 1.5 m deep.

Percolation Tanks Percolation tanks are artificially created surface water bodies, submerging a land area with adequate permeability to facilitate sufficient percolation to develop the ground water. Percolation tanks are artificially created surface water bodies, submerging a land area with adequate permeability to facilitate sufficient percolation to develop the ground water.