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Bonifacio S. Labiano
Division Manager A, Irrigation Engineering Center (IEC),
National Irrigation Administration (NIA), EDSA,
Diliman, Quezon City, Metro Manila, Philippines

ABSTRACT

In the Philippines, focus on agricultural water management dwells on improving flood control, dam operations, planning database, stewards' capability, and irrigation performance. Quest for improved agricultural water management, of course, precedes the climate change buzz and for improved irrigation system performance also precedes the rice self-sufficiency thrust.

Government efforts to adapt to climate change and to achieve rice self-sufficiency, in fact, make policies and programs on agricultural water management evolve more responsive to necessity. Resultant higher priority for expanding irrigation area (physical intervention) garnered a matching reform, "increased priority for improving irrigation performance" (operational intervention).

To achieve higher irrigated area, cropping intensity and crop yield, NIA adopts measures that improve water adequacy, control, distribution, conservation, monitoring and stewardship. Simultaneous with this priority thrust is the crash program for the development of agricultural vulnerability maps and vulnerability mapping capability on climate change impact. Outputs of this program are essential in the identification and positioning of adaptation and mitigation measures to lessen exposure and risk to the impact of climate change and extremes.

Devastating torrents and floods with substantial inflicted damages and losses due to very intense rainfall, ascribed to climate change and tropical cyclones, already hit the country in many occasions. Taking a cue from these events, NIA deemed critical the immediate reassessment of the adequacy of the design flood and spillway size of its reservoir dams to check necessity for rectification. Fiercer water allocation competition among the different sectors of society amid "diminishing" available plain water deserves responsible integrated water resource planning.

Harvesting cum storing of rainfall and runoff in ponds and reservoirs is a prudent way of tapping benefits from the hydrologic cycle and rainy season, and of bracing for dry spells and droughts. NIA thus also had accorded greater emphasis on the implementation of reservoir irrigation systems—considering the resiliency of such impart when water crises like droughts and El Niño strike.

Keywords: water management, irrigation operations, irrigation management, agricultural water, irrigation policies, irrigation strategies, irrigation thrusts, irrigation modernization, water productivity, climate change

INTRODUCTION

Irrigation development status

Of the 3.126 M ha of irrigable lands in the country (Table 1), 1.567 M ha already has irrigation facilities—equivalent to an irrigation development level of 50%, as of end of 2011 [Labiano, 2012]. Of this irrigation area, 50% is in national irrigation systems (NISs), 36% is in communal irrigation systems (CISs), and 14% is in private irrigation systems (PISs). NISs are developed and operated by the Government (through the National Irrigation Administration or NIA), while CISs are developed by NIA but operated by irrigators associations (IAs). PISs are the ones established by individual farmers or small groups of farmers at their own initiative, effort and expense, i.e. at no assistance whatsoever from Government or NIA.

Irrigation operations status

Of the irrigation area, 75% is irrigated in wet season, 70% in dry season, and 2% in 3rd season, which gives 146% cropping intensity a year [Patrocinio, 2012]. This resultant suboptimal cropping intensity with the inability to serve water to an appreciable section of the irrigation area is reflective of scant irrigation performance. This situation is attributable to water supply shortage, water distribution inequitableness, and irrigation system dysfunction, including water logging during wet season. During wet season when there is adequate water supply from rainfall and streamflow, rainfed sections of irrigation areas exist though due to inability to deliver irrigation water.

Operations modality reversal

Under typical operations modality, NIA is the superintendent of the irrigation systems—deciding, for instance, which of the NISs and CISs are priority for rehabilitation. Under the Irrigation Management Transfer Program (IMTP), IAs in covered NISs become the stewards of the NISs or parts thereof, with NIA relegated as IAs' co-steward. IMTP implementation is an adjunct reform to the NIA Rationalization Plan (RatPlan)—a five year-duration organizational reform intended to transform NIA into a more viable agency. Implementation of the NIA RatPlan concludes this year with cumulative total of 2,129 senior staff retiring from service, but IMTP implementation progress is as yet short of the envisaged level.

Rice self-sufficiency thrust

Government targets to hit full rice self-sufficiency end of 2013, which also targets zero rice importation beyond 2013, with irrigation development at the centerpiece. NIA gets 65% of the national rice program budget and its quota is to contribute 35% of the target incremental increase in palay production for 2011 to 2013 [DA, 2012]. NIA's share would come from projects executed that generate new irrigation area, restore water deprived irrigation area, and rehabilitate water deficit irrigation area (Table 2). NIA's budget strategy (Table 3) thus targets area rollouts higher than those in the Food Staples Sufficiency Program (FSSP) so any accomplishment shortage will not hamper FSSP [NIA, 2012].

Vital Performance Indicators

Oversight agencies list irrigation sector performance indicators like decrease in water use per unit yield (m3/kg) and decrease in water use per unit area a year (m3/ha-yr). These indicators, reflective of the necessity for aggressive agency initiative to improving water productivity vis-à-vis diminishing plain water supply, are vital. Irrigation systems, by design, have operating discharge capacity and water levels that needed kept for such to run good—suggesting difficulty in increasing water productivity. This is in view of the fact that to reduce water diversion or allocation to any section of irrigation system would not result in lesser water use but would result in lesser irrigated area.

EMERGING NEEDS

Climate change adaptation

A decade before climate change became a buzzword, NIA already had started adopting countermeasures (Table 4 and Table 5) to water-related operations constraints [Labiano, 2012], which are akin to the effects of climate change. NIA has rich experiences in shifting from continuous irrigation to rotational irrigation as a means of minimizing crop loss and yield reduction when droughts strike. Recurrent water shortage also had pushed NIA to be further inventive—inferred from the expanding adoption of drainage reuse systems as a water-augmenting intervention. NIA sees retrofitting of offtakes, using a simple weir as cross regulator and notched weir as offtake intake with gate shutter, as rectification to inequitable water distribution.

Agency rationalization initiative

Under NIA's five year-duration RatPlan implementation, which ends in 2012, total number of regular positions decreases from 11,414 to 3,819 [Caguioa, 2012]. Total number of regular staff (warm bodies) also declines from 5,283 to 3,154—with 2,129 senior staff availing of the early retirement with add-on incentive under RatPlan. Most of the residual junior staff is less experienced that an increase in workload could be very overwhelming, so NIA has to match the RatPlan with a global training program. Training on hydrology analysis, irrigation design, and water management is most sought so NIA, through ongoing foreign-assisted projects, had embarked on such but in limited scale. NIA is nonetheless hopeful that, through forthcoming foreign-assisted projects, it can conduct training courses in a more massive scale, to include IAs as beneficiaries.

Water allocation competition

Competition for water allocation among the agricultural, residential, commercial and industrial sectors is becoming fiercer—aggravated by diminishing plain water resource. This is exemplified by two landmark events that happened in the Angat Maasim River Irrigation System (AMRIS) in Region 3—one that gets water from the Angat Reservoir Dam. The committee on Angat Dam operations cancelled the dry season rice crop (as 1st event) in AMRIS in 1998, diverting the AMRIS allocation as household water for Metro Manila. This decision takes relevance on the fact that the reservoir storage by that time was low, which required precautionary measures to lessen household water crisis in Metro Manila.

Said committee also decided (as 2nd event) to deduct 15 m3/sec from the water allocation of AMRIS, and reallocated such as household water for Metro Manila. This deduction gets premise on the fact that the serviceable area already had shrunken by about 5,000 ha due to progressive landuse conversion from agricultural to non-agricultural. To restore system operating efficiency, restoring the 15 m3/sec deduction is necessary with a new reservoir dam and system redesign cum reconstruction as the chosen interventions.

ALLEVIATION STRATEGIES

Parcellary map upgrading

Distortions in parcellary maps of irrigation systems, like missing and shrunken landholdings, also distort data on irrigation development level and irrigation service fee (ISF) collection. Distorted size of irrigation area per system results in inaccurate water allocation in canal offtakes—often ending up in water inadequacy or overage. This situation, made more apparent by water-deprived tail-end sections of irrigation areas, often molds the distorted public perception of "inefficient" irrigation systems. NIA sees the need to correct that perception from inefficient irrigation systems to scant irrigation performance, besides upgrading parcellary maps using irrefutable base maps [Labiano, 2012].

Hydrometeorological data monitoring

Most basic in planning irrigation operations and water management are rainfall and streamflow data but very few irrigation systems in the country has rain and stream gauges. Used in hydrology analysis for irrigation rehabilitation projects often are insufficient extrapolated offsite data, which give out results with characteristic uncertainty. With the advent of climate change, better selection and positioning of countermeasures to lessen damages to irrigation facilities and standing crops is possible with sufficient database. Recognizing the importance of such database, NIA will establish rain and stream gauging stations in selected irrigation systems starting next year (2013).

Diversified cropping promotion

Landclass-based landuse or cultivating non-rice field crops (instead of rice) in light-soil sections of irrigation areas is a known means of conserving irrigation diversions. If these sections were planted to rice, concerned farmers would tend to divert more water to establish paddy water layer while offsetting high percolation rate. Landuse shift from rice to non-rice field crops in light-soil farmlands is however sluggish because farmers felt more secure in growing the staple crop (rice) due to guaranteed market and price. Another factor that dissuades farmers from growing non-rice field crops in light-soil farmlands is the high volatility of erstwhile good market and price opportunity. Some enterprising farmers though continue venturing in diversified cropping, despite high risk of losses, because of the prospects of possible windfall crop income.

Disaster impact assessment

Tropical cyclones batter the country, in terms of strong winds and severe floods, every year—devastating irrigation facilities and agricultural crops besides habitation areas. In assessing the value of damages to irrigation infrastructure, the cost entailed in reconstructing (executing temporary and permanent solutions) said facilities are the data reported. Executing temporary solution is often resorted to where immediate remediation measure for damaged irrigation facilities is necessary to avert possible damage to standing crops. After harvesting the crop or when the crop is free from risk, executing the permanent remediation measure takes place—dependent however with the availability of funds.

Oversight agencies now push for process standardization and threshold setting for assessing damages caused by natural disasters, including the value of collateral losses [OCD, 2012]. Delayed repair of a breached irrigation canal also cuts the access road, besides irrigation service, thus causing foregone income from undelivered agricultural products (e.g. vegetables). An emerging issue pertinent to this situation is which office should handle compensation for claim for losses associated to delayed repair of breached infrastructure.

Water resource governance

A recent accounting indicated that about 30 agencies are executing water-related functions involving monitoring, regulation, development and utilization, with certain overlap. Recent prolonged flooding in the province of Bulacan (Region 3), which spurred blame-hurling among a number of agencies triggered decisions to name a water czar. Levied on this water czar is the task of establishing an apex water agency with mandate to coordinate the planning, development and utilization of water resources in the country [NEDA, 2012]. Part of the mandate is to oversee the upgrading and execution of the protocols for the operations of reservoir dams—in particular, making of decisions to the execution of pre-emptive spill.

Flood forecasting-warning systems

Huge torrents and floods in increasing number, ascribed to climate change, wrought severe devastation, in terms of casualty numbers, and infrastructure and property damages. Big multipurpose reservoir dams in the country already have their respective flood forecasting and warning system (FFWS) as decision-support facility for dams operations. These FFWSs are essential in rendering decisions as to when to do pre-emptive spill and how much of the reservoir inflow to retain and spill to avoid aggravating downstream flooding. Observed trends of more recurrent huge torrents and floods caused by torrential rainfall trigger initiatives for the establishment of FFWSs in flood-susceptible areas. This initiative, which NIA also sees necessary in small reservoir dams, is now a standard intervention advocated for adoption in identified flood-prone habitation areas. Concerned government agencies, responding to minimizing disaster devastation and vulnerability, are now pushing out communities lying in torrents and floods risky areas.

Flood retarding facilities

Safe gradual disposal of flood waters from tropical cyclones and monsoon rainfall is a growing concern vis-à-vis the thrust for minimizing flood devastation in cultivation and habitation areas. A familiar strategy is to divert flood waters into flood-retarding ponds (e.g. marshes, pools and lagoons) at the height of flooding period for gradual release after the flood starts to subside. More of these flood-retarding ponds maybe necessary with the advent of climate change but natural depressions in correct size do not exist in right number and locations. A man-made flood-retarding pool with large storage capacity now exists in the Bonifacio Global City (in Taguig City)—a blueprint for mitigating urban or rural flood hazards.

Reservoir hydrology re-analysis

More recurrent huge torrents and floods, known impact of climate change, and devastation incidence of such suggest just how vulnerable the country is. Very intense rainfall and the resultant huge floods in watersheds enter irrigation reservoirs as huge inflows, which deserve proper regulation. When these floods come when reservoir water is at critical high level, proper disposal of such floods is a primary but sensitive decision. Following standard dam operations protocol, timing and flowrate of pre-emptive spill must consider current reservoir level, flood pool volume, reservoir inflow rate, downstream water levels and dam spillway capacity.

Safety and integrity of reservoir dams are, of course, dependent on the dam operations protocols and the spillway discharge capacity. In view of the increased recurrence of very intense rainfall and huge floods due to climate change, NIA sees the need for a re-analysis of the design floods for the reservoir dams. At present, NIA operates 15 small reservoir irrigation systems with dam height of 12-32 m (Table 6) and over 10 more (Table 7) are in the NIA's budget strategy to start implementation within the next two years.

SUMMARY

Current situation

  • (a) Achievements in irrigation development level (50%) and irrigated cropping intensity (146%) are as yet at insufficient mark to sustain full rice self-sufficiency. Aware of the eroding effect of unabated booming population growth and concomitant rising rice requirement, increased advocacy for much higher achievements evolves.
  • (b) Status of irrigation system operations is distinguished by suboptimal cropping intensity (146%)—ascribed to constraints in water supply, water control, and irrigation functionality. Influenced by the notable presence of water-wasteful and water-deprived zones of irrigation areas, public perception of inefficient irrigation systems emerges.
  • (c) Shift in irrigation operations modality from "typical" (NIA as the irrigation steward) to "atypical" (IAs as the irrigation stewards) is slow so needing a strong shove. Delay in setting NIA-IAs acceptable sharing ratio on irrigation service fee (ISF) collections is one factor that stalls IMTP execution behind the NIA RatPlan
  • (d) Thrust for full rice self-sufficiency end of 2013 exemplifies the predominance of irrigation development as an intervention to staple food production. NIA in fact is getting 65% of the rice budget for 2011-2013 and required to contribute 35% of the target incremental palay production for the same critical period.

Emerging needs

  • (a) Threat of global climate change is becoming more serious—manifested by several high-casualty high-destruction torrents and floods that already hit the country. This pushes NIA the development of agricultural vulnerability maps and mapping capability on climate change essential in positioning of mitigating measures.
  • (b) Impact of rationalization plan implementation to NIA is structure downsizing, distinguished by the reduction in personnel complement from 11,414 to 3,819. This reform demands rigorous capability enhancing for the leftover younger less-experienced staff vis-à-vis bigger workload further increased by the FSSP implementation.
  • (c) Sternness in water allocation competition, triggered by steady growth and rising demands of the various society sectors, makes water supply for agriculture diminishing. This presses NIA to embark on physical and operational interventions, focusing on water storage, augmentation and conservation, to secure water supply for irrigation.

Alleviation strategies

  • (a) Efforts in irrigation water management, i.e. right discharge to the right place at the right time, are pestered by inaccurate landholding sizes besides defective water control. NIA thus decided to implement projects involving the upgrading of parcellary maps using satellite imagery, as irrefutable base maps, and RS-GIS technology.
  • (b) Planning for irrigation system operations—in particular, setting of programmed area for dry season cultivation—is constrained by lack of hydrometeorological data. NIA thus deemed necessary to include as project components the progressive establishment of automatic rainfall and streamflow gauging stations in irrigation systems.
  • (c) Methodology in disaster impact assessment—in particular, assessing damages and losses caused by natural calamities—is now the subject of standardization efforts. For its part, NIA had participated in an interagency workshop on this matter, which highlighted that such is complementary to disaster mitigation and reconstruction work.
  • (d) Reforms in water resource governance started with moves to integrate all water-related functions and agencies under the coordination and regulation by just one apex agency. These moves, which include ongoing legislation, are in response to ardent call to mitigate or avert damages by natural disasters and to optimize resource utilization.
  • (e) Demand for flood forecasting-warning facilities, similar to those installed in big multi-purpose reservoir complexes, is on the rise in flood-vulnerable areas. NIA also sees urgent the establishment of such facilities in the small reservoir irrigation complexes (watershed, reservoir and flood plains) as decision-support systems.
  • (f) Demand for flood retarding facilities, e.g. reservoirs, marshes, and man-made pools, is becoming more popular due to the recurrence of intense rainfall cum huge floods. This scheme involves the diversion of flood waters at the peak of floods to marshes as temporary storage and the gradual release of such when the floods start to recede.
  • (g) Urgency of reservoir hydrology re-analysis had grown in view of the necessity to ensure the safety of reservoir dams from possible devastating overtopping events. NIA is conceptualizing the scheme that it should adopt relative to the re-analysis of probable maximum flood and design flood magnitude for its dam spillways.

CONCLUSION

Enhancement of agricultural water management and utilization is happening in two fronts, viz. national development level (Table 8) and irrigation development sector (Table 9). This comes about with the integrated goals of achieving rice self-sufficiency, averting force majeure devastation, and confronting diminishing plain water supply.

On rice self-sufficiency, top programs include expanding irrigation area and improving irrigation performance, with special attention on averting natural devastation. Climate change and water competition, aggravated by watershed degradation and El Niño episodes, are putting a strain on the dependability of water supply for irrigation.

On climate change, priority programs include enhancing hydrometeorological monitoring, expanding flood forecasting, and building-up irrigation resilience. Developing vulnerability maps, putting-up flood pools, unifying devastation assessment, and re-analyzing reservoir hydrology are also in the short list.

On diminishing plain water supply, core programs include integrated water governance, rationalizing NIA's structure, and innovating irrigation operations modality. Also in priority are empowering irrigators associations, training irrigation personnel, upgrading parcellary maps, and promoting water-saving and -conserving technologies.

REFERENCES

  • Caguioa, Wilma E. "Implementation Status of the NIA Rationalization Plan," NIA-JICA's TCP3 Brainstorming Conference, Quezon City, Philippines, July 2011.
  • Department of Agriculture (DA). "Food Staples Sufficiency Program 2011-2016: Enhancing Agricultural Productivity and Global Competitiveness," Quezon City, Philippines, June 2012.
  • Labiano, Bonifacio S. "Climate Change Impact Adaptation and Mitigation Measures in Irrigation Systems," ATI's Training of Trainers, Iloilo City, Philippines, February 2012.
  • Labiano, Bonifacio S. "Enhancing the Efficiency and Effectiveness of Irrigation in the Philippines," NAST-DOST Round Table Discussions, Makati City, Philippines, March 2012.
  • Labiano, Bonifacio S. "Food Staples Sufficiency Program: Status of Irrigation Component (NIA Part)," NEDA Cabinet Committee Meeting, Manila, Philippines, February 2012.
  • National Economic & Development Authority (NEDA). "Water Resource Management Office," Public Consultation Conferences, Quezon City, Philippines, April 2012.
  • National Irrigation Administration (NIA). "NIA Budget Strategy 2011-2016: Supporting the Gains of the Food Staples Sufficiency Program," Quezon City, Philippines, June 2012.
  • Office of Civil Defense (OCD). "Disaster Impact Assessment Mechanics," NDRRMC's Stakeholders Consultation Conference, Pasig City, Philippines, June 2012.
  • Patrocinio, Dexter G. "Status of Irrigation Projects (OD-Monitored) and Irrigation Operations," NIA Managers Conference, Nueva Ecija, Philippines, May 2012.


Index of Images

  • Table 1 Status of irrigation development

    Table 1 Status of irrigation development

  • Table 2 NIA's quota to the FSSP

    Table 2 NIA's quota to the FSSP

  • Table 3 NIA's budget strategy 2010-2013

    Table 3 NIA's budget strategy 2010-2013

  • Table 4 Interventions to water overage

    Table 4 Interventions to water overage

  • Table 5 Interventions to water shortage

    Table 5 Interventions to water shortage

  • Table 6 Existing small reservoir irrigation systems

    Table 6 Existing small reservoir irrigation systems

  • Table 7 In-pipeline small reservoir irrigation projects

    Table 7 In-pipeline small reservoir irrigation projects

  • Table 8 National program thrusts and policy direction

    Table 8 National program thrusts and policy direction

  • Table 9 National program thrusts and policy direction

    Table 9 National program thrusts and policy direction

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