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Soil and Water
Conservation Techniques
Er. Anil K. Jadhav
Assistant Professor
IWDM Faculty, WALMI, Aurangabad
Clim
ate
Ch
ange
Market Forces
Fractured Vulnerable Communities
Th
e C
onte
xt
Depleted Natural Resources
The Effects of Environmental Degradation
and Water Scarcity
Women and Children are not spared
Malnourished children
Long distances to fetch fire wood
Tanker fed Villages
Cattle Camps during droughts
Over 40,000 farmers committed suicide since the past 12 years
Every 8 hours one farmer takes its life
15% of country suicides take place in Maharashtra with over 50% of them resulting from debts.
More that 50% of those who died are between 20 to 45 of age- most productive years.
Nearly 2.8 Million of 3.2 million cotton farmer in Vidarbha are defaulters.
Numbing Statistics….
Watershed Development can
change this miserable life…
A watershed is a geographic area that
collects rainwater and channels
it into a stream, a
waterway and a river.
It is a socio-ecological unit.
this line bounds the watershed area of the shown drainage line
the divide line of a drainage area
Darewadi - 1996D
arew
adi -
19
96
Darewadi - 1999D
arew
adi -
19
99
Darewadi - 2009
Strengthens Relationships
Rejuvenates & Diversifies Natural Resources
Revitalizes Local Economies
Dar
ewad
i -2
00
9
What is Watershed Development?
1. Area Treatment
1.Area Treatment
3. In-Situ Soil & Moisture Conservation
1. Area Treatment
1. Area Treatment
3 typesArea Treatments
Drainage Line Treatments
In-Situ water Conservation
Regenerating Natural Resource Base
• NOT A NEW IDEA
• However done on individual , ad hoc basis: Not Systematic and Integrated.
• Regenerated Resources – Utilization –equitable and sustainable manner.
• Critical factor is involvement of local communities and capacity building of local institutions.
Watershed Development isSocio-technical intervention.
Where the local inhabitants Plan, Organize, Implement and Monitor various treatments and maintain
their watersheds.
Along with Social Disciplines like Shramdan (Local Contribution)
Ban on Free GrazingBan on Tree Cutting
Principle 1: Ridge to Valley
To decentralise soil and water conservation treatment
Most degraded land gets first priority
Poor land owned by poor farmers is treated first
Increases the time of concentration of fast
flowing water
Increases the stability of downstream structures/ treatments
Principle 2: Scientific Execution1. Area Treatment
1.Area Treatment
3. In-Situ Soil Conservation
1. Area Treatment
1. Area Treatment
Principle 3 Treatments on Contour Line
Water harvested in treated
area remains at uniform level
leading to even soil moisture
It helps in prevention of
breakage of treatments.
It helps in land levelling over
a period of time
1197.45
819.5 773858
11530
0
300
600
900
1200
1500
Rainfall (mm) Green Veg.(ha.) Barren Land (ha.)
Rainfall, Green Vegetation and Barren
Land (Jan.'96 and Dec.'99)
January 1996 December 1999
Darewadi - 1996
Darewadi - 2009
Principle 4: Vegetative Cover is the Key
Principle 5 Watershed Planning is Land Use Planning
Net Plan
1. Soil Texture
2. Soil Depth
3. Soil Erosion
4. Land Slope
Land Capability Class
(LCC- I to VIII) Land Use Plan
Watershed Treatment
Plan
Principle 5 Land Use according to Land Capability
Class I Intensive
Cropping System
Class II Conservation
Cropping System
Class III Restrictive
Cropping System
Class IV Agri-
Horticulture/ Agro-Forestry
LAND SUITABLE FOR CULTIVATION
Principle 5 Land Use according to Land Capability
Class V Pasture/
Range/ Woodland
Class VI Afforestation/
Pasture/ DrylandHorticulture
Class VII Grazing/
Woodland/ Wildlife
Class VIII Recreation/
Wildlife
LAND not SUITABLE FOR CULTIVATION
Principle 6 Social Unity and Disciplines
Catalysing Creative Irritants for Democratic processes in an atmosphere of Relaxed Tensions
• Community Institutions
• Watershed bare-foot Technical Experts
Social Disciplines
• Controlled Grazing of Animals
• Ban on uprooting/ cutting of Trees
• Ban on use of Borewells for Irrigation
• Sustainability and Equity in Groundwater use
Community Ownership
• Voluntary Labour (Shramdan)
• Community Share in Watershed Investments
If not here, where? If not now, when? If not me, who?
Micro
Irrigation
Control on Extraction of Groundwater
Water Productive Crop Pattern and Cultivation Practices
Soil and Water Conservation Structures
Principle 7 Water Budgeting and Management
• Re-deepening or De-silting of Structures
• Gap filling, Pruning and Nurturing Plantations/ Grass beds
Maintenance
• Shaping of soil and stone bunds
• Increasing the Cross section of bund
• Removing the breakagesRepair
• Creation and Use of Maintenance Fund
• Annual Assessment and Action on Maintenance and Repairs
Systems
Principle 8Maintenance and Repair of Structures
Watershed Development and Time of Concentration (Tc)
Point-R… farthest point from Outlet
Outlet- Point of Concentration
Tc is time taken by raindrop
fallen at point R to reach the
outlet.
Rain falling beyond Tc time creates flood situation at
outlet.
More the Tc, more effective the watershed
treatments are!
In Watershed Development, Tc is increased
by doing treatments so
that, “running water
walks, walking water
stops and stopped water
infiltrates.”
Area Treatments linked with Land UseAfforestation (AF): Water Absorption
Trench (WAT)
AF: Continuous Contour Trench (CCT)
CC- Compartment Bund
Agro-Horticulture
Crop Cultivation (CC): Contour Bund
Farm Pond
Crop Cultivation (CC): Graded Bund
Pasture: Contour Stone Bund
CC: Contour Stone Bund
Crop Cultivation (CC): Terracing
Drainage Line Treatments
Stone Gully Plugs
LBS
Cement Nala Bund
Earthen Nala Bund
Gabion Structure
Stepped CNB
Area Treatments
1. Continuous Contour Trenches
Planning and excavation should be
from the Ridge part
are of 0.60 x 0.30 m size
‘ties’ are kept at 5-10m interval
‘horns’ are given at the end
Contour should be followed strictly
Useful for soil and moisture
conservation2. Refilling of Continuous Contour
Trenches (RCTs)
Depth of refilled trenches should be at least
0.50 m
Refilling should be done 1-2 months before
the onset of monsoon
It is the best measure for survival of
plantation in ‘Drought Prone Area’
Continuous Contour Trenching
• Since 1993..in barren land
• Contour line demarcation from the ridge line
• 60cm wide & 30cm deep trenches
• Dump on the downstream side with plantation
Slope % Horizontal
interval m
0 to 4 10 or 12
4 to 8 8
8 to 15 6
15 to 33 4
Staggered Guard Trenches
3. Contour Stone Bund (CSB)
Are taken on those area where soil
excavation is not possible because of
abundant quantum of stone or boulders.
These are constructed along the contour line
Useful for reducing velocity of runoff and it
arrests flowing soil.
4. Contour Stone farm Bund
It is an age old practice
It should be constructed across the slope
or on the contour
Skilled persons are required for its
construction
It lasts for long time and over the period
of time the field become leveled.
It saves the downstream treatments
from the intense storm.
It should be strictly taken on contour
3 rows or lines of WATs shall be taken
on uniform slopping land , one at the
top, second at the middle and last at
the lower portion.
Extra runoff is diverted into
natural gullies.
Max.size of WAT is 1 x 1 m
4. Water Absorption Trenches (WAT)
Contour Bunds and Field
Bunds on Waste Lands and
arable lands to improve
soil moisture retention and
control erosion.
5. Contour / Field Bunds
And promote growth of
grasses, trees and crops.
Uncultivable
0.65 ha
Gully
Well
Nallah
RoadCulturable 1.08 ha.
FB
FB
Sketch of Survey No. 349
Drain
Sketch of Selected Survey Number - Existing Situation
1
2
3
4
56
7
8
9
10
Uncultivable
0.65 ha
Gully
Well
Nallah
Road
GS
Culturable 1.08 ha.
OutletGP
CCT
RFB
RFB
EB
Sketch of - Survey No. 349
Drain
Pits
Sketch of Selected Survey Number - Proposed Treatments
Village Cadastral Map
PARTICIPATORY NET PLANNING (PNP)
It should be taken once area
treatment is completed
Reduces the velocity of runoff and
conserve the soil
Loose Boulder structure-
Batter on both the side’’
Stone Gully Plugs in series
Drainage Line Treatments
Gabion Structure
Check Dams and Nala
Bunds are constructed
for harvesting surplus
runoff.
Earthen Nala Bund
Check Dam
Drainage Line Treatments
EARTHEN NALA BUND
