1 of 16

MICRO WATERSHADE MANAGEMENT

Presented by

KAMLESH R KAMBLE

Asst. Professor

2 of 16

MICRO WATER SHADE MANAGEMENT

INTRODUCTION :
Integrated watershed management programme is the strategy adopted in the India for sustainable development of dry land areas.
One of the definitions of watershed management is “the process of creating and implementing plans, programs, and projects to sustain and enhance watershed functions that affect the plant, animal, and human communities within a watershed boundary.
In spite of sufficient rainfall, people have to face water scarcity for their use especially supply in summers in most of the areas. This is mainly due to large runoff which is responsible for water loss as well as soil loss of the land.
Watershed management involves the judicious use of natural resource with active participation of institutions, organization, peoples, in harmony with the ecosystem.

3 of 16

�

OBJECTIVES OF WATERSHADE MANAGEMENT :

Watershed development programme in India envisages promotion of multiple objectives. They include the following:

To promote the economic development of the village community.
To encourage restoration of ecological balance in the village.
Special emphasis to improve the economic and social condition of the resource-poor and the disadvantaged sections of the Watershed Community such as the asset less and the women.

Along with above mentioned objectives following are the technical objectives of the programme

To control runoff and degradation and thereby conservation of soil and water.
To utilize the runoff water for useful purpose.
To protect, conserve and improve the land of watershed for efficient and sustained production.
To check soil erosion and to reduce the effect of sediment yield on the watershed.
To moderate the floods peaks at downstream areas.
To increase infiltration of rainwater.
To enhance the ground water recharge.

4 of 16

TRENCHES

WHERE THE SLOPE OF LAND IS BETWEEN 10-25%, ROWS OF TRENCHES ARE DUG ALONG CONTOUR LINES IN A STAGGERED FASHION. THEY HOLD WATER FLOWING DOWN THE SLOPE AND HELP IMPROVE LOCAL SOIL MOISTURE AND TRAP SILT.

CONTOUR BUNDS

ON SLOPES LESS THAN 10%, CONTOUR BUNDS ARE CONSTRUCTED. THESE ARE MUD STRUCTURES WHICH HELP CHECK THE VELOCITY OF WATER AND SOIL EROSION, MUCH LIKE THE TRENCHES BUT ON GENTLER SLOPES.

5 of 16

CONTUR LINES

Where the slope of land is between 10-25%, rows of trenches are dug along contour lines in a staggered fashion. They hold water flowing down the slope and help improve local soil moisture and trap silt.

NALA BANDH

These are small dams made of loose angular rocks and boulders, built on seasonal streams with a catchment area less than 50 hectares and on slopes less than 20%. In a long series, they help arrest the unbounded flow of water as well as trap silt and prevent soil erosion.

6 of 16

LOOSE BOULDER

7 of 16

�

LOOSE STONE BANDHARA :

Loose stone bandhara is built to store water along the watercourse of spring or a stream where stones of various sizes are available. Bandhara so developed will store the water behind it and allow the water to percolate in the ground. It results in enriching the water table of surrounding area. The adjoining land holder can use this stored water for cultivation. As shown in the picture loose stones are arranged across the flow of water to get a height of 3 to 4 feet. Width at the base is always 1.5 times the height of Bandhara.

8 of 16

VANRAI BANDHARA

Vanarai bandhara are constructed across a stream or small river using gunny bags refilled with locally available soil or sand. These bags are sealed properly and are arranged in the form of a wall barrier. This is a temporary structure built across water course to collect the water as well as to reduce the velocity of stream so that infiltration rate of water increases. It helps in replenishing the aquifer below the river bed resulting in increase in ground water level in the surrounding area. Normally Vanarai Bandhara is constructed at the end of monsoon period and it lasts till the onset of the next monsoon.

9 of 16

GABION STRECTURE

On streams with catchment area between 50-500 hectares and relatively flatter land, rock and wire dams called Gabion Structures are built. Since the volume and velocity of runoff is too high for loose boulder checks, an external material in the form of a wire mesh is introduced for the first time to hold the rocks in place. It slows down the speed of water running down a stream and increases the duration of stream flows, resulting in recharge of groundwater. It also traps silt while allowing water to pass through it, protecting the downstream structures from siltation.

10 of 16

PERCOLATION TANK

On the main stream of the watershed construct earthen dams. These earthen dams or nala bunds, when made in the upper part of the catchment, serve as percolation ponds that help recharge wells in the lower reaches of the watershed. When built near farms, they are used for direct irrigation. Most of these dams hold water all year round, providing water in the crucial summer months, which is a sign of a healthy dam and a successful intervention.

CEMENT LAYER CHECK DAM

The most important part of the structure is the exit which needs to be designed in a way that allows excess water to flow making sure that it never over tops the bund.

11 of 16

FARM POND

Farm ponds are small tanks or reservoirs constructed for the purpose of storing water essentially from surface runoff. Farm ponds are useful for irrigation, water supply for the cattle, fish production etc. The design and construction of farm ponds require a thorough knowledge of the site conditions and requirements. Some sites are ideally suited for locating the ponds and advantage of natural conditions should always be taken.

12 of 16

CHECK DAMS

The check dams or in-stream storage structures with or without gated arrangements are to be capable of safely releasing the anticipated design flood without affecting the safety of the structures with minimum afflux in the upstream. Water can be stored in such a pond / reservoir towards the end of monsoon. Check dams, upto a height of 3.0 mt. can be constructed across small tributaries / nallah / drainage channel within the banks and streams in middle and higher reaches .They require regular maintenance.

13 of 16

CULVERT BANDHARA

A Semi-circular structure is erected around the culvert as shown in the picture. This helps in accumulation of soil that flows with the water. It also improves percolation rate and increases the water table of the surrounding area.

14 of 16

KOLHAPUR BANDHARA

15 of 16

CONCLUSION

Watershed catchment area is totally depending upon rainfall for water as there is no Perennial source of water. If watershed development techniques are implemented, it will result in increase in the irrigation potential which ultimately increases the crop production which will increase living standard and economic condition of people
These types of the watershed management programme can effectively solve problem of irrigation and drinking water problems.
Due to various watershed measures like farm pond, check dam, vanrai bandhara they should be implemented to cope up with the drought conditions.

After implementation of such programmes also the Maintenance of these structures should be done regularly e.g. silt removal from the lake, wells and check dam it will result in increased water storage capacity of above structures and increase ground water table.