ground water recharge

NATIONAL POWER TRAINING INSTITUTE,NAGPUR

METHODS OF GROUND WATER RECHARGING.

Made By: Pravin V. Appa

Guided by: Satish Kane Sir CIVIL ENGINEERING DEPTARTMENT

Groundwater :

1)Groundwater is the underground water which occurs in the saturated zone of earth surface.

2)Cracks and pores in existing rocks makes this ground water reservoir.

3)Ground water utilized through wells and tube wells.

Groundwater Recharge:

Groundwater Recharge:1)Developing of artificial underground

reservoir by artificial recharging for storing water underground called recharging of underground water.

2)It is quite advantages as compared with dams,reservoiers etc.

3)Artificial recharging technique is under intensive research and is being increasingly used in france, Germany etc.

Groundwater Recharge:

Appropriate Technology

Water conservation and groundwater recharge techniques

Water harvesting cum supplementary irrigation techniques

METHODS OF RECHARGING:

1)Spreading method:

In this method water is spreads over the surface of permeable open land and pits from where it is directly infiltrates to shallow aquifer.

In this method water is stored in shallow ditches or spread over open area by constructing low earth dykes.

Rate of recharging depends upon permeability of spreaded area and depth of water stored.

Also some chemicals are added in soil to increase rate of recharging.

1)Spreading Method :

2)Recharge well method: In this method water is injected into the

bore holes. Water is fed into recharge wells by

gravity or pumped under pressure. Ordinary wells also perform the work of

recharging water during off season.

2)Recharge well method:

3) Induced infiltration method:

In this method water table gradient is increased from source of recharge.

In this method special type of wells are constructed near the banks of river having radial collector.

The percolating water is collected from radial collector and the discharge as recharge in to lower level aquifer ‘B’ as shown in fig.

3) Induced infiltration method:

Artificial Ground Water Recharge

Artificial recharge to ground water is a process by which the ground water reservoir is augmented at a rate exceeding that obtaining under natural conditions or replenishment. Any man-made scheme or facility that adds water to an aquifer may be considered to be an artificial recharge system.

Artificial Ground Water Recharge Techniques

Methods of artificial recharge in urban areas :

Water spreading Recharge through pits, trenches, wells,

shafts Rooftop collection of rainwater Roadtop collection of rainwater Induced recharge from surface water

bodies.

Computation of artificial recharge from Roof toprainwatercollection :

Factors taken for computation : Roof top area 100 sq.m. for individual

house and 500 sq.m. for multi-storied building.

Average annual monsoon rainfall - 780 mm.

Effective annual rainfall contributing to recharge 70% - 550 mm.

Benefits of Artificial Recharge in Urban Areas : Improvement in infiltration and reduction in

run-off. Improvement in groundwater levels and

yields. Reduces strain on Special Village Panchayats/

Municipal / Municipal Corporation water supply

Improvement in groundwater quality Estimated quantity of additional recharge

from 100 sq. m. roof top area is 55.000 liters. Reduces waterlogging

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