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DROUGHT MANAGEMENT IN THE PHILIPPINES

Presented by:

PACITA F. BARBA VILMA A. VERGARA

ASEAN DROUGHT WORKSHOP 2015 18-20 August 2015 in Bangkok, Thailand.

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CONTENT

A. BACKGROUND

B. HISTORY OF DROUGHT EVENTS

C. RESPONSE OF THE STATE AND OTHERS

D. POLICY FRAMEWORK AND WATER ALLOCATION PRACTICES

E. DATA AND MODELLING PRACTICES AND NEEDS

F. WATER EFFICIENCY MEASURES

G. AREAS OF IMPROVEMENT

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BACKGROUND

The Philippines is an archipelago consists of 7,107 islands. It has an aggregate area of approximately 300,000 sq. km with a total population of about 100 Million.

Its climate is influenced by the complex interaction of various factors

- geography and topography - principal air streams - ocean currents - inter-tropical convergence zone - tropical cyclones, which are classified as tropical depression, tropical storm or typhoon depending on their intensities

An average of 19 – 20 tropical cyclones a year entering to Philippine Area of Responsibility. Of which, 8-9 tropical cyclones crossing the country triggering floods and landslides

The country has abundant rainfall, yet some areas are semi-arid

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Background…

The seasonal and inter-annual extreme climate variability are significantly influenced by the El Nino Southern Oscillation Phenomenon (ENSO)

In the Philippines, major droughts years are associated with El Nino events

El Nino years in the country are indicated by weak typhoon activity, entering in the PAR, fewer numbers of typhoons and less intense typhoons.

Semi-arid areas is exacerbated by El Nino events, which is now

occurring at a two- to three- year cycle from previous five-year interval

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HISTORY OF DROUGHT 1

The Philippines is a natural disaster-prone country because of its location on the Pacific Ring of Fire and close to the equator makes the Philippines prone to earthquakes and typhoons including drought.

The earliest recorded drought occurred in 1583 in the immediate aftermath of the El Nino of 1581-82. It adversely affected local economies and harvest causing food shortage and famine.

A series of protracted droughts between 1683 and 1704 had profound effect on the socio-economic and demographic development.

Since the end of the 17th Century, there has been an increase in frequency of food shortages and famines that have occurred from that time to the present. The last drought occurred associated with El Nino was in 2010

___________1 Warren, J.F., Climate Change and the Impact of Drought on Human Affairs and Human History in the Philippines, 2013

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From 1960-2010, there are 15 weak to strong El Nino episodes. The recent El Nino episode was in 2010.

The strongest was in 1997-1998 El Nino episode.

History of Drought..

Angat reservoir received 40% of the average inflow causing water level down to its critical level , 11 months of no release for irrigation, curtailed water supply for Metro Manila and no power generation from this dam.

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This 4th quarter of 2015, it was predicted that there will be an occurrence of El Nino that may result into water shortage in 2nd Quarter of 2016.

History of Drought..

Reduced streamflow Insufficient water for irrigation

Crop failure

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History of Drought..

Year Damages

1982 -1983 Rice and Corn production loss of 6.4 x 105 metric ton, insurance claims amounted to PhP 38 Million, Hydropower generation loss was PhP 316 Million

1986-1987 Estimated agricultural damages of PhP 47 Million and hydropower generation loss of Php 671 Million

1989-1990 Estimated rice and corn production loss of 5 x105 metric ton, hydropower generation loss of PhP 348 Million and 10% cutback in water production for Metro Manila

1991-1992 Agricultural losses of PhP 4.09 Billion, 20% shortfall of water supply in Metro Manila

1997-1998 Rice and corn production loss of 622,106 metric ton and 565,240 metric ton, respectively amounting to PhP3.Billion, water shortages, forest fires and human health impacts

Damages of major drought associated with strong El Nino from 1980-2010

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RESPONSE OF THE STATE AND OTHERS

Between the 16th and 19th centuries, the explicit action plan taken by the Archibishop is to hold rogativos or public prayers. It is the duty of everyone, and especially the church ministers to pray for abundant rain and to keep away from illness (Selga, 1920).

In early 20th century, the government speeded rice importation in order to offset the anticipated rice shortage and maintain its price at normal value.

Early 1980’s, the government has put in place early warning systems, organized agency committees and task force, and implemented relevant programs and projects.

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Response of the State and others…

An institutional structure for emergency relief and drought response was developed in 1987-1988 lead by the National Disaster Risk reduction and Management Council (NDRRMC).

The Drought Early Warning and Monitoring System (DEWS) was

developed n 1986-87 El Nino. This provides timely weather condition assessment and other information needed by various end-users.

The Inter-agency Committee on Water Crisis Management was created in 1987. It is responsible for water management during drought situation including setting up of priorities on water use.

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Response of the State and others…

An Inter-agency Task Force on El Nino was created in 1997 to formulate action plan and develop strategic programs to help the affected populace to cope with the phenomenon and to minimize its adverse effects.

The drought action plans are generally connected to food security programs considering its adverse effect in agriculture.

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POLICY FRAMEWORK AND WATER ALLOCATION PRACTICES

Water Code of the Philippines (PD1067) provides that:

• Art. 22- Between two or more appropriators of water from the same source of supply, priority in time of appropriation shall give the better right, except that in times of emergency the use of water for domestic and municipal purposes shall have a better right over all other uses; Provided, that where water shortage is recurrent and the appropriator for municipal use has a lower priority in time of appropriation, then it shall be his duty to find an alternative source of supply in accordance with conditions prescribed by the Council.

• Art. 23 – Priorities may be altered on grounds of greater beneficial use, and other similar grounds after due notice and hearing, subject to payment of compensation in proper cases.

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Water Code of the Philippines (PD1067) provides that:

• Art. 26- Where water shortage is recurrent, the use of the water pursuant to a permit may, in the interest of equitable distribution of benefits among legal appropriators, be reduced after due notice and hearing

• Art. 27– Water users shall bear the diminution of any water supply due to natural causes of force majeure.

• Art. 28- Water permits shall continue to be valid as long as water is beneficially used; however, it maybe suspended on the grounds of non-compliance with approved plans and specifications or schedules of water distribution; use of water for a purpose other than that for which it was granted; non-payment of water charges; wastage; failure to keep records of water diversion, when required; and violation of any term or conditions of any permit or of rules and regulations promulgated by the Council.

Policy Framework and Water Allocation Practices …

National Water Resources BoardWATER ALLOCATION OF ANGAT RESERVOIR

Climate Forecast(PAGASA)

Status of Dam and Reservoir(NPC)

Power Requirement (NPC)

Irrigation Requirement(NIA)

Water Supply Requirement(MWSS)

Reservoir SIMULATION(NWRB)

Discussion on the results of the simulations. Recommendation of TWG on allocation

Technical Working Group

Top Level Management

Decision and Approval by (NWRB Board)

Water Release from Reservoir(NPC )

Inflow assumptions

TWG INPUT

Status of Dam and Reservoir & FFWS (NPC)

The water allocation of water in Angat Reservoir is thru a Technical

Working Group, composed of the National Power Corporation (NPC),

National Irrigation Administration (NIA), Metropolitan Waterworks and

Sewerage System (MWSS), PAGASA and NWRB as chair.

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DATA AND MODELLING PRACTICES AND NEEDS

The model in estimating the water availability in the reservoir for allocation is by simulation analysis.

In simulation analysis, the changes in storage content of a finite reservoir are calculated by the continuity equation. A time period of one month is adopted.

Data used are historical inflow data, water supply and irrigation requirements, and taken into account the climate forecast and release rules

The outcome of the analysis is the projected water levels of the reservoir for the next three to six months. This determines the volume of water for allocation.

There is a need for an optimization model by stochastic dynamic programming, downscaling of climate forecast and its translation to inflow, and decision support system

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WATER EFFICIENCY MEASURES

The measures and practices adopted by the government and other supporting institutions prior to or during drought to reduce drought are as follows:• Rehabilitation/repair of irrigation canals to improve irrigation efficiency• Leak repair of distribution pipes• Shifting of planting calendars or early planting• Planting of early maturing varieties and other alternative crops that

consume less water• Promotion of water-saving technologies• Community-based watershed management for sustainable water

resources• Promotion of water recycling and re-use• Information dissemination campaign on water conservation by tri-media

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AREAS OF IMPROVEMENT

Enhance knowledge and skills on effective drought management

Development of analytical tools for drought forecasting models with high level of adequacy and reliability, decision support system.

Development of more appropriate monitoring and early warning systems for drought

Development of policy measures or enabling environment in terms of access to new innovations and technologies

Building of infrastructures such as storage dams to capture high flows during rainy season and utilize during dry season

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THANK YOU

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Telefax No. (632) 9202641 / 9202654Website: www.nwrb.gov.ph