Small-Scale Irrigation Systems (SSIS)
Small-scale irrigation can be defined as irrigation, usually on small plots, in which small farmers have the controlling
influence, using a level of technology which they can operate and maintain effectively. Small-scale irrigation is,
therefore, farmer-managed: farmers must be involved in the design process and, in particular, with decisions about
boundaries, the layout of the canals, and the position of outlets and bridges. Although some small-scale irrigation
systems serve an individual farm household, most serve a group of farmers, typically comprising between 5 and 50
households.
In the Philippines, Small-Scale Irrigation Systems (SSIS) are irrigation infrastructures with limited service areas,
constructed within 180 days in locations where permanent or continuous water sources are not available. Small-Scale
Irrigation Systems (SSIS) are implemented by the Department of Agriculture (DA), often under the Bureau of Soils and
Water Management (BSWM). They include Small-Water Impounding Projects (SWIPs), Small Diversion Dams, Small
Farm Reservoirs (SFR), Shallow Tube well (STW), Spring Development, Pump Irrigation System Using Renewable
Energy Sources For Prime Movers which provide irrigation in times of drought.
Small-Water Impounding Projects (SWIPs)
SWIP is water harvesting method and storage structure consisting of an earth embankment, spillway, outlet works, and
canal facilities. It is designed for soil and water conservation and flood control by holding as much as water as possible
during the rainy season for productive use during dry season. It provides supplemental irrigation water for intensified
crop production which may substantially increase farmers’ income. In addition, SWIP also contributes to the water
requirements of livestock production, aquaculture, power generation and recreation.
The Small Water Impounding Management Committee (SWIM) once headed by the Department of Public
Works and Highways (DPWH) classified small water impounding projects as earthen dams with structural
heights of not more than 30 meters and a volume storage not exceeding 50 million cubic meters.
Figure 1. Main Components of Small-Water Impounding System
Source: PHILIPPINE AGRICULTURAL ENGINEERING STANDARD PAES 609:2016 Rainwater and Runoff
Management – Small Water Impounding System
Uses of Small-Water Impounding Projects
1. Collect and store surface run-off water during the rainy season for immediate and future use.
2. Conserve soil and water
3. Irrigate Crops
4. Source of water for livestock
5. Minimize Flooding
6. Minimize soil erosion and siltation of fertile bottom lands
7. Use as a community recreational area
8. Groundwater recharge
Coverage Area
• With at least service area of 15 hectares.
Qualified Beneficiaries/ Proponent
• Registered Farmers’ organizations (e.g. SWISA) or group of at least 15 farmers who are willing to be
organized
Mandatory Requirements:
•
Right of way agreement for reservoir area, dam site, canal, access road and other structures for new
construction;
• Topographic and engineering maps; and
• Engineering plans and detailed design, quantity take off estimates, and program of work to be signed and
sealed by Licensed Agricultural Engineer per RA 8559 also known as Agricultural Engineering Act of 1998.
Development cost:
• Maximum of PhP 300,000 per ha of service area for new construction
• Maximum of PhP 200,000 per ha of restored area for rehabilitation or improvement.
Small Diversion Dams
A diversion dam is a concrete or rock-fill structure with a height of 0.50 – 3.0 meters designed to divert portion of stream
flow to point of use. A diversion dam serve the purpose of raising the eater level in order to redirect the water to the
required destination. The water diverted by means of diversion dams is used to supply irrigation systems and reservoir.
Figure 2. Small Diversion Dams
Construction of Diversion Dams
The design of diversion dams can be any of the following type:
1. Embankment Style Dam
The design and construction features of embankment style dam are:
 The weight of the dam is constructed to oppose the water pressure coming over it.
 It is a dam made of materials available within the surrounding area of the site.
 The materials used can be sand, gravel and rocks.
 The materials plus the impermeable membrane like clay provide integrity to the structure.
 The cost is less compared to other types of dams.
2. Buttress Style Diversion Dam
 This dam is constructed using angle supports on the downstream of the dam.
 The supports are fixed to the wall which counteracts the force of water on the dam.
 The dam is built across the wide valleys that do not have bed rock foundation.
 It requires extensive steel works and labor.
 It is expensive and rarely built.
3. Arch Style Diversion Dam
 An arch type dam have the top face arched shape.
 The Arch shape effect counteract the force of water.
 It is constructed in narrow canyons.
 It is made out of concrete.
 Arch dams curves horizontally.
4. Gravity Style Diversion Dam
 Gravity dam counteracts the force of water by its own weight.
 It is constructed using masonry or cement.
 The foundation for gravity dams are constructed over bed rock foundation.
Coverage Area
With at least service area of 15 hectares
Qualified Beneficiaries/ Proponent
• Registered Farmers’ organizations (e.g. SWISA) or group of at least 15 farmers who are willing to be
organized;
Mandatory Requirement
• Right of way agreement for canal and access road and other structures for new construction;
• Topographic and engineering maps; and
• Engineering plans and detailed design, quantity take off estimates, and program of work to be signed and
sealed by Licensed Agricultural Engineer per RA 8559 also known as Agricultural Engineering Act of 1998.
Development cost:
• Maximum of PhP 200,000/ha of service area for new construction
• Maximum of PhP 100,000 per ha of restored area for rehabilitation or improvement
Small Farm Reservoir (SFR)
Small Farm Reservoir (SFR) is an impounding and storage facility with concrete or plastic as lining and protection of
embankment. These are used to collect rainfall and run-off for immediate and future agricultural use. SFR is built to
accommodate excess rainwater during the rainy season. The water collected is then used as source of supplementary
irrigation for the cultivation of high-value economic commodities in the dry season.
Figure 3. Small Farm Reservoir
Coverage Area:
• At least 0.5 ha production area per unit
•
Qualified Beneficiaries/Proponent
• Individual farmer with at least 0.5 ha production area; and
• For group of farmers with a minimum of 2.5 ha production area and have a common site for SFR, they may
be provided with SFR equivalent to 5 units.
• National and Regional Research Centers of DA and SUCs and research and demonstration farms of LGUs.
Development cost
• A maximum subsidy of PhP 50,000 per unit and PhP 250,000 for aggregate of 5 units for new construction.
• A maximum subsidy of PhP 25,000 per unit and PhP 125,000 for aggregate of 5 units for rehabilitation.
Shallow Tubewells (STWs)
Shallow Tubewells (STWs)consists of a tube or pipe vertically set into the ground at a depth of 6 to 20 meters with pipe
diameter of 50 mm, 75 mm or 100 mm, it is designed to lift water from shallow aquifer for irrigation using pump and
engine set.
Figure 4. Shallow Tubewells (STWs)
Coverage Area:
• With at least 1.0 to 3.0 ha production areas within the shallow groundwater.
Qualified Beneficiaries/Proponent
• Group of 3-5 farmers with a minimum 3 ha production area;
• Farmer Associations, Cooperatives, and other related organizations; and
• Individual farmer with at least 3 ha production area for rice; and
• Individual farmer with at least 1.0 ha production area for high value crops.
Counterpart Scheme;
• Beneficiaries are responsible for the installation of their tube wells; and operation and maintenance of their
system
Development cost;
• The total cost of pump and engine set for STW depends on the size and brand, ranging from PhP 30,000 to
PhP 100,000.
• The cost of drilling and pipes ranges from PhP10,000 to PhP 30,000.
Spring Development
Spring Development consists of concrete storage tank or intake structure, and PE pipes or concrete canals for
distribution by gravity.
Coverage Area
• Production area of at least 0.5 ha for HVC
• 1.0 ha for other crops per farmer.
Qualified Beneficiaries/Proponent
• Group of at least 3 farmers; and
• With total production area of at least 1.5 ha for high value crops and 3.0 ha for rice and other crops.
Development cost
• Maximum of PhP 200,000 per ha of service area
PUMP IRRIGATION SYSTEM USING RENEWABLE ENERGY SOURCES FOR PRIME MOVERS
Alternative Prime Movers for Pump Irrigation Systems consist of pump and prime movers using renewable energy
sources, storage tanks and piped distribution systems. In these systems, the water sources are already developed
(e.g. river, lakes, and wells) that require energy to lift water to point of use. These include Hydraulic ram pump, Solar
pump, and Wind pump.
Figure 5. Solar Power Pumps System
Figure 7. Wind Pump System
Figure 6. Ram Pumps System
Solar water pumps
Solar water pumps can supply water to locations which are beyond the reach of power lines. Commonly, such places
rely on human or animal power or on diesel engines for their water supply (Omer, 2001). Solar water pumps can replace
the current pump systems and result in both socio-economic benefits as well as climate related benefits. The water
supplied by the solar water pump can be used to irrigate crops, water livestock or provide potable drinking water.
A solar water pump system is essentially an electrical pump system in which the electricity is provided by one or several
PhotoVoltaic (PV) panels. A typical solar powered pumping system consists of a solar panel array that powers an
electric motor, which in turn powers a bore or surface pump. The water is often pumped from the ground or stream into
a storage tank that provides a gravity feed, so energy storage is not needed for these systems.
Ram Pumps System
The basic principle behind ram pumps is to use a large amount of water falling a short distance to pump a small amount
of water to a higher elevation. Typically, only 2% to 20% of the water flowing through a ram pump system will actually
be delivered to the storage tank or trough. The remainder is overflow and directed back into the stream. Ram pumps
have two main operating characteristics: lots of water flows out the waste valve, and there is a cyclic nature to the
pumping action which is somewhat noisy.
Wind Pump
Wind Pump is a device that converts kinetic energy from the wind into mechanical energy to pump water
through windmills, to obtain the following:
 Source of fresh water from wells; and
 For draining low lying areas of land
Coverage Area:
• Areas with developed/existing dependable water sources.
Qualified Beneficiaries/Proponent:
• At least 3 farmers with minimum 3.0 ha irrigable area; and
• Research Centers of DA, LGUs and SUCs.
Development Cost:
• Maximum subsidy of PhP 200,000.00 per ha for solar and ram pump irrigation system for high value crops;
• Maximum subsidy of PhP 200,000 per ha for ram pump for rice; and
• PhP 150,000.00 per ha for wind pump irrigation system for high value crops
Counterpart Scheme
• Farmers to provide water source (e.g. well) and O&M of the system.
Roles and Responsibilities of Implementing Agencies of Small-Scale Irrigation Systems
BSWM
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provides guidelines on project development
provide technical assistance
assist in the preparation of eng’g design
assist in the project field implementation
Lead the annual updating of SSIP Master Plan per RFO;
Provide technical assistance to RFOs, LGUs and Farmers’ Association (e.g. SWISA) including capability
building through conduct of specialized training courses for trainors;
Monitor the planning and implementation of SSIPs by the RFOs; and
Consolidate and prepare monthly reports of DA-RFOs for submission to DA.
DA-RFOs
• Update and review their annual proposed SSIPs per their regional Master Plan for submission to BSWM;
• Implement the approved and funded SSIPs;
• Provide technical assistance to LGUs and other agencies/organizations (e.g. SWISAs);
• Monitor the operation and maintenance of the existing SSIPs; and
• Submit monthly reports to BSWM during projects’ implementation.
LGU
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implement project thru a MOA
direct construction supervision
provide counterpart
negotiate right of way problem
provide agri-support services
facilitate the organization of Farmers Associations with assistance from BSWM and DA-RFUs
FARMERS ASSOCIATION
• provide counterpart in form of labor
• responsible in the project O & M
• monitor project implementation at their level