INTRODUCTION IRRIGATION AND DRAINAGE ENGINEERING I

A. IRRIGATION vs. DRAINAGE

IRRIGATION application of water into the soil

A. IRRIGATION vs. DRAINAGE DRAINAGE removal of excess water within or on the soil can be natural or artificial

B. OBJECTIVE OF IRRIGATION AND DRAINAGE To create an environment favorable to plant growth by maintaining Water balance Salt balance

B. OBJECTIVE OF IRRIGATION AND DRAINAGE ADVANTAGES increase cropping efficiency increase crop productivity and yield increase cropping intensity

C. DEVELOPMENT OF IRRIGATION IN THE PHILIPPINES 1. Pre-Spanish and Spanish Period small gravity irrigation system communal

C. DEVELOPMENT OF IRRIGATION IN THE PHILIPPINES 2. American Regime (1900-1936) First Irrigation Law BPW Irrigation facilities

Construction and repair 12 small & medium scale for rice irrigation

91,000 ha

C. DEVELOPMENT OF IRRIGATION IN THE PHILIPPINES 3. Commonwealth and Japanese Regimes (1937-1946) Little irrigation development 4. Early Independence Period (1947-1965) Rehabilitation projects NIA creation 51 small & med scale project

122,000 ha

C. DEVELOPMENT OF IRRIGATION IN THE PHILIPPINES 5. Expansion Period (1966-1984) Pantabangan Dam (1969) NIA policy making Medium & Large Scale Projects

D. ROLE OF IRRIGATION AND DRAINAGE ENGINEERS FINITE FRESH WATER SOURCE

Irrigation represents the largest portion of the total water consumption in

agriculture.

Source: WEPA, 2012

Irrigated rice accounts for about half the total harvested rice area and 70% of the total rice production. fishery

27%

irrigation 72%

others 1%

Philippine Irrigation Systems Since 1960s, irrigation systems, dams and concrete canals have been constructed to provide regular water service especially during the dry season.

Irrigation is an important strategy of the government towards agricultural productivity and food self-sufficiency. Almost 50% of the total annual expenditure of the government is allocated to improve the Philippine agricultural water resources (UN Water, 2013).

About 9.7 million ha or 32 % of the total land area of the country is devoted for agriculture, of which 3.02 million ha is potentially irrigable but only 1.68 million ha is actually irrigated (BAS, 2015)

National Irrigation System (NIS) the largest irrigation

scheme, servicing about 44 % of the total irrigated land

Five principal river basins in the country provide water for the NIS

Cagayan River basin Agno River basin Mindanao River basin Agusan River basin Pampanga River basin

The service area of the NIS increased rapidly from 200,000 ha in the mid-1960 to 420,000 ha in 1990s. But its ability to deliver sufficient irrigation water over the whole service area during the wet season has declined over time from almost 100% in 1960s to 70% in the recent years. The actual irrigated area of the NIS during the dry seasons increased from 30% in 1960s, 60% in 1980s and 70% in the recent years, attributed to the completion of the largest NIS - the UPRIIS and the MARIIS.

Poor Performance of Irrigation Systems

deficient water supply low water-use efficiency of the irrigation subsector siltation and losses in the irrigation canals due to the degradation of watershed and severe erosion during typhoons poor maintenance and management of the irrigation facilities underestimation of the field water requirements and water losses through diversion the overestimation of the service areas

D. ROLE OF IRRIGATION AND DRAINAGE ENGINEERS Development of New Irrigation Systems Rehabilitation of National and Communal Irrigation Systems Improving the Performance of Irrigated Agriculture Farming Systems Diversification and Intensification Research and Extension

Sustaining or expanding the irrigation base is the key to food security and poverty alleviation in many developing countries

INTRODUCTIONA. IRRIGATION vs. DRAINAGEA. IRRIGATION vs. DRAINAGEB. OBJECTIVE OF IRRIGATION AND DRAINAGEB. OBJECTIVE OF IRRIGATION AND DRAINAGEC. DEVELOPMENT OF IRRIGATION IN THE PHILIPPINESC. DEVELOPMENT OF IRRIGATION IN THE PHILIPPINESC. DEVELOPMENT OF IRRIGATION IN THE PHILIPPINESC. DEVELOPMENT OF IRRIGATION IN THE PHILIPPINESD. ROLE OF IRRIGATION AND DRAINAGE ENGINEERSSlide Number 11Slide Number 12Slide Number 13Philippine Irrigation SystemsSlide Number 15Slide Number 16Slide Number 17Slide Number 18Slide Number 19D. ROLE OF IRRIGATION AND DRAINAGE ENGINEERSSlide Number 21