Project preparation activities are continuously undertaken to have wider base for the selection of projects for implementation. These include project identification, investigations, feasibility studies, plan formulation, project packaging, and detailed engineering.
IMPLEMENTATION OF IRRIGATION PROJECTS
Types of activities
Generation of new areas refers to the construction of facilities and structures for the provision of irrigation and drainage services to presently rainfed areas, idle lands, and other identified potential irrigable areas.
Rehabilitation and improvement of irrigation systems will increase efficiency and effectiveness of water delivery to currently irrigated areas. This addresses the wear and tear of facilities and structures.
Restoration works aim to bring back into operation the non-functioning service areas in NIS and CIS. This entails reconstruction of facilities and provision of additional structures.
Types of projects
Single purpose projects are solely for irrigation.
Multipurpose projects have other components aside from irrigation, like hydropower generation, fishery, domestic water supply, flood control, recreation, and tourism.
Irrigation packages involve implementation of two (2) or more projects in different locations; and may combine generation of new areas, rehabilitation, and restoration of NIS and CIS.
Types of systems
NIS are large and medium schemes, usually covering more than 1,000 hectares (ha), and constructed by NIA. These are jointly operated and maintained by NIA and the farmer-beneficiaries thru their Irrigators Associations (IA).
CIS are small scale schemes generally 1,000 ha or less in area. These are constructed by NIA with the participation of the IAs. The O&M of the CIS is turned over to the IAs upon project completion.
Schemes of development
Run-of-the-river or diversion projects entail the drawing of water under controlled conditions directly from the flow of rivers or streams.
Storage or reservoir projects involve the construction of storage dams to impound water and to release water as needed to be drawn from a diversion dam downstream. These projects are usually multipurpose to include other components and can be large scale (i.e., Upper Pampanga River Integrated Irrigation Systems (UPRIIS) and Magat River Integrated Irrigation Systems (MRIIS) or small scale (small reservoir irrigation projects for CIS).
Pump projects entail lifting of water from underground or rivers, streams, and lakes. Pump systems are also common in some storage or diversion schemes to lift water to irrigate areas on higher elevation or pump groundwater to supplement available supply from the river.
Sources of water for irrigation
Surface water which include rivers, streams, and lakes.
Groundwater is pumped thru shallow tubewells and deep tubewells.
Types of projects
Dam, intake gate, sluice gate, headgate, long-crest weir, end check.
Canal system: main canal, laterals, sub-laterals in big systems, main farm ditches in small systems, supplementary farm ditches, flumes, siphons, turnouts.
Access and service roads, including bridges where needed.