This document discusses watershed management through micro irrigation systems. It begins by providing some background on water scarcity globally and increasing water demands. It then defines watersheds and watershed management. Micro irrigation systems like drip and sprinkler irrigation are presented as a way to improve water use efficiency in agriculture compared to traditional flood irrigation. The document outlines the components, design process, and scheduling of micro irrigation systems. It also introduces the concept of pressurized irrigation network systems to facilitate distribution to micro irrigation systems from surface water sources like canals in a cost-effective manner. Overall, the document promotes watershed management through micro irrigation as a way to optimize water usage and irrigation practices.

1. Watershed Management by
Micro Irrigation System
Er. Chirag R Shah
Research Scholar,
Department of Environmental
Science & Engineering
Marwadi University ,Rajkot

2. Schematic diagram of MIS
Installation

3. Some Facts about Water
• Only 2.5% of the world’s water is freshwater
and most of this are in the form of polar ice-
caps.
• Water use has increased by 70% since 1970
• A recent report by Credit Suisse stated that by
2025 18 countries will experience water
demand beyond supply capabilities
• It takes up to 5000 lt of water to produce 1kg
of rice.

4. Watershed Management
• What is a watershed??
• Watersheds can be simply define as an area
where the water is in any form is drained to
a common point.
• In a closed watershed , the water converges
to a single point inside the basin ,which may
be a permanent lack ,dry lack or
underground water (DAS,MM,2013)

5. What is a watershed Management ?
• For a systematic sustainable development of the
watershed , its proper management is important with
respect to taking into consideration of various hydrologic
and hydraulic components.
Hydrologic Components Hydraulic Components
• precipitation,
• infiltration,
• evaporation, evapotranspiration,
• run off
• ground water.
• flood,
• River bank erosion
• Drainage basin management
• Soil erosion
• Water quality
• Water management
• Water harvesting structures
• Water supply & Irrigation
• Agriculture & water application to
crop and plants

6. Classifications of Watersheds (Bali,1978)
Macro Watershed
(> 50,000 Hector)
Sub-Watershed
(10,000 to 50,000 Hector)
Milli-Watershed
(1000 to10000 Hector)
Micro-Watershed
(100 to 1000 Hector)
Mini-Watershed
(1-100 Hector)

7. Watershed Management – Definition
• 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.
• Watershed management is the integrated use
of land, vegetation and water in a
geographically discrete drainage area for the
benefit of its residents, with the objective of
protecting or conserving the hydrologic
services that the watershed provides and of
reducing or avoiding negative downstream or
groundwater impacts.

8. Watershed Management through
Irrigation Management
• What is Irrigation ?
– Supplying water to plants in an artificial manner is called
irrigation .
Why Irrigation Management ?
water usage (APES,2009,CH-13)
– Domestic: 10%Agriculture: 70%Industrial use: 20%
– Farmer use 70% of worlds fresh water ,but 60% of it is
wasted due to leaky irrigation systems(WWF-IE,2017).
– Flood irrigation method delivers far more water than is
needed for crop growth and typically loses 40% of the
water through evaporation, seepage, and run off.
– More efficient and environmentally sound irrigation
technologies can greatly reduce water waste on farms

9. TYPES OF IRRIGATION METHODS
SURFACE IRRIGATION
(FLOOD IRRIGATION)
SUB SURFACE
IRRIGATION
MICRO IRRIGATION
1. BASIN
2. BORDER
3. FURROW
SUB SURFACE
IRRIGATION 1. DRIP IRRIGATION
2. SPRINKLER
IRRIGATION

10. • Water use efficiency is very low up to 35-40% due to
substantial conveyance and distribution and
Evaporation losses.
• Tail End Beneficiaries not get equal quantity of water
due to seepage & other losses .
• Water requirement very higher up to 50mm
• Cultivation cost increases due to excess labor , de
weeding & fertilizer excess utilization .
• Ground water level decreases.
PROBLEMS WITH FLOOD IRRIGATION

12. • Water is supplied at required interval and quantity
using pipe network , emitters and nozzles.
• Conveyance & Distribution losses reduced
complete results in higher water use efficiency up
to 90% in Drip Irrigation & 70% in Sprinkler
Irrigation.
• Reducing Energy requirement , weed problems,
soil erosion and cost of cultivation.
Why Micro Irrigation Systems

13. MICRO IRRIGATION vs FLOOD
IRRIGATION

14. Area which can be covered under flood irrigation
with available water ( Ha)
= Discharge(Q) x 2.88 x Irrigation Interval ( 4day)
Water requirement for flood for one irrigation (50mm)
Area which can be covered under Micro irrigation
with available water ( Ha)
= Discharge(Q) x 2.88 x Irrigation Interval (1day)
Water requirement for MIS for one irrigation (4mm)
Water Requirement for flood for one irrigation : 50 mm
Irrigation interval for flood : 4 days
Water Requirement for MIS : 4 mm
Irrigation interval for MIS : Daily

15. • In Micro Irrigation water is directly applied to root
zone of the crop.
• It need to satisfy only moisture requirement of the
crop.
• Water Requirement is 4mm per Day i.e. 4 Lit per
Square meter and it will be given every day or
alternate day.
• Undulated Land, rolling topography , hilly area,
barren land can be irrigated due to Pressurized
system.
HOW WATER USE EFFICIENCY INCREASES

16. Root Zone Coverage

17. • Improve Efficiency of irrigation System
• Ensure Sustainability of Irrigation System
• Improve Performance of Irrigated Agriculture
• Achieve Optimum Utilization of Water
• Achieve Equity in Water Distribution
• Increase Production per Unit of Water
OBJECTIVE OF MIS

18. • The meaning of “Wara” is Turn & “bandhi” is
Fixation. “Warabandhi” means rotation of water
supply according to fix schedule.
• It is system of equitable water distribution by turns
according to a predetermined schedule specifying
day , time and duration of supply to each irrigation
in proportion to land holding in the outlet water
source command area.
Warabandhi/ Rotational Water Supply

19. • To Provide Water to every holding within command
area Irrigation Networking is essential .
• For MIS –Pressurized Irrigation Networking is
required.
• To Ensure Design Discharge at every outlet.
• Farmer’s participation (PIM) is required.
Requirements of Water Scheduling

20. • A schedule of water supply indicating the time of
starting and closing to a particular land holding is
known as “Roster” of Turns.
• In MIS entire network in PINS , hence no issue of
non getting water to Tail Plots of Command.
• Entire command area is sectioned in equal parts
and accordingly valve sectioning designed for MIS
scheduling.
Water scheduling in MIS

21. Step 1 :- Finding Crop Water Requirement per Day
Step 2 :- How many Emitters (Drippers) to use &
how much Emitter lines
Step 3:- Determining the watering days & time
Steps to Determining Watering Schedule
in Drip Irrigation

22. Irrigation Rate ( Unit mm / hour)
= (Dripper Discharge1)/ (Crop Spacing2)/ (Raw Dist3.)
1-liters per hour , 2- meter , 3 – meter
Operating Hours per Shift ( Unit hour)
= (Irrigation Rate1) / (Crop Water Requirement2)
1-mm per hour , 2- mm per day
Total Working Hours per day
= (Operating hours per Shift ) / (No. of Shifts per day)
Formula for Valve Sectioning

24. • Crop water requirement have scientifically
quantified by plant’s Evapotranspiration (ET)
• ET is combined water lost from both transpiration
from plant leaves and evaporation from soil and
wet leaves.
• ET is also know as crop or plant water use.
ET- Evapotranspiration

25. • Distance between Crop Rows(Lateral Spacing)
• Distance between Plants (Dripper Spacing)
• Dripper Discharge ( Liters per Hr)
• Crop water requirement
• Pump Suction Head
• Pump HP
• Discharge at Pump Outlet
Total working Hours Depends upon

26. Q (lps) = HP X 75 x Motor Efficiency *
Head
• Motor Efficiency is generally taken as 68%
(Shah,CR,2015)
CALCULATING PUMP DISCHARGE (Q in liters
per second)

27. Pressurized Irrigation Network
System (PINS)
• PINS is an innovative concept which facilitates
all the basic requirements of MIS viz.
(a) Daily application of water and
(b) Pressurized flow using Surface water
source (Canals)
• Acts as an interface between Canal waters and
MIS

28. WHAT IS PINS ?
• PINS= Pressurized Irrigation Network System
• It is a interface between a canal [flowing
under gravity] flow and the MIS system
• It comprises of Pipe Network with controls,
Pumping Installations, Power Supply,
filtration, intake well/Diggy
• It is a common and shared infrastructure
[by Group of farmers] facilitating individual
beneficiary for installing and operating MIS

29. Levels of Pressurization
Sr.
No
Level of
Pressurization
(Command Block)
Capital &
Operational Cost
Power connections
Per VSA
1
VSA ( 300 to 500
Ha)
Very High 1 connection
2 Chak (40 to 60 Ha) High 5-6 connections
3
Sub- Chak ( 5to 8
Ha)
Low
About 50
connections
 Obviously pressurization at Terminal point i.e. Sub-Chak level
would be the most economical option but would also require
more number of power connections.
 Evidently to take the advantage of Cost and feasibility aspects of
power connections Sub-Chaks are re-oriented radially from the
centre of a Chak and pressurized flow is resorted to only at the
head of sub-chaks.

30. 30
Concept of PINS- Network Bridge Between Canal and MIS in
the Field
T
U
B
E
W
E
L
L

31. (PINS)
(PINS)
(PINS)
Sub Chak
(Chak Level 50 ha)
(Feasible & Pragmatic)
Gravity
(Sub Chak Level- 8 ha)
(Feasible)
Source
BC /Distry (Perennial)
Chak-1
Chak-2
Chak-3
Chak-4
Chak-6
Chak-5
PIPES-PRESSURE FLOW
Reference:-
(VSA Level 300-400 ha) (Costly-not feasible)
SCHEMATIC LAYOUT SHOWING PINS AT VARIOUS LEVELS
WITHOUT STORAGE -CONSIDERING CONTINUOUS CANAL FLOW
COMMAND BOUNDARY
Assumptions:
(1) BC / Distry up to 8.5 cumecs &
above operate on CVC - i.e. they are
perennial canals-canal itself is
considerd as reservoir.
(2) Pump House at the head of Pressurisation.
(3) Only command in the vicinity of BC /
Distry can be considered (nearly 1.0 Km.)
Pumping
House
Pumping
House
(Sub Chak - 8 ha)
Diagram NO-1

32. Minor ( 1/2 Discharge)
continuous operation
Sub Chak-2Sub Chak -1
Sub Chak-4
Sub Chak-5
Sub Chak -6
Sub Chak-3
Storage
Pond
1 day
Chak Level (50 ha)
Pumping
House
PVC/HDPE
Gravity Main
(5 TO 8 hq)
Agri Supply
Step down
Transformer
(1 No/Chak)
PINS pipe
Assumptions:-
8 Hrs Agri Supply
1 no Step-down Transformer Per Chak
Pressure Mains(100mt.)-Radial
Storage Pond For 1 day
Storage Intake well at Centre of a Chak
SCHEMATIC LAYOUT SHOWING PINS AT CHAK LEVEL WITH
1 DAY STORAGE AND 8 HRS. ELECTRIC SUPPLY.
Intake well
Diagram NO-2
PINS-PRESSURE PIPES
PVC-GRAVITY MAINS
Reference:-
COMMAND BOUNDARY

33. • The total area considered for planning is divided into
Chaks & Sub Chaks.
• After Finalizing Chaks & Sub chaks , the alignment of the
water course and field channel network have been
determined.
• The Water Course and Field Channel has been designed
with capacity of 0.61 lit/sec/Ha.
• The bed width is kept 0.3 m depth of water is taken as
0.2 , side slope is kept 1.5 : 1 and wetted perimeter as
1.021 m.
• The value of rugosity constant is adopted as 0.018
• The field drain and collecting drains have been aligned
according to topography of land.
Design Criteria for Open Field Channel

34. INTIGRATED IRRIGATON SOLUTIONS

35. References
1. Das,M.M,2013,Watershed Management ,PHI, New Delhi.
2. Bali,Y.P.,1978,Watershed Management ,CSWCRTI ,Dehradune.
3. Shar,C.R.,2015, Participatory Irrigation Management by
implementing Pressurized Irrigation Network System (PINS)
along with Micro Irrigation System (MIS) at various G.W.R.D.C.
Ltd. operated community tube wells in Gujarat, All India
Seminar on " Participatory Irrigation Management-Promises and
Problem, SC-IEI ,Ahmedabad.
4. WORLD WILD LIFE RESEARCH ON Digital intervention critical
for irrigation system, Indian Express,16.06.17,M Rajendran.

36. THANK YOU