Water Adaptation Strategies and Agricultural Productivity Under Changing Climate

Working Paper No. 2015-12 Water Adaptation Strategies and Agricultural Productivity Under Changing Climate

Manolo G. Villano, Dulce D. Elazegui, Precious R. Zara, Raem Dominic S. Brion and Agnes C. Rola.

Center for Strategic Planning and Policy Studies (formerly Center for Policy and Development Studies) College of Public Affairs and Development University of the Philippines Los Baños College, Laguna 4031 Philippines

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The CSPPS Working Paper series reports the results of studies by the Institute faculty and staff which have not been reviewed. These are circulated for the purpose of soliciting comments and suggestions.

This paper was published as FSE/CIDS Working Paper 2014-10 by the University of the Philippines Center for Integrative and Development Studies (UP CIDS). The views expressed in the paper are those of the authors and do not necessarily reflect those of CSPPS, the agency with which the authors are affiliated, and the funding agencies, if applicable.

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The Director Center for Strategic Planning & Policy Studies (formerly CPDS) College of Public Affairs University of the Philippines Los Baños College, Laguna 4031 Philippines Email: [email protected]

LIST OF ACRONYMS

BAS Bureau of Agricultural Statistics BRIS Balanac River Irrigation System CIS Communal Irrigation Systems CLUP Comprehensive Land Use Plan CI Cropping Intensity DA-RFU Department of Agriculture - Regional Field Unit DENR Department of Environment and Natural Resources DRRM Department of Public Works and Highways DPWH Disaster Risk Reduction and Management ENSO El Niño Southern Oscillation FUSA Firmed-up Service Area FGD Focused Group Discussion

GOCC Government-Owned and/or Controlled Corporations KII Key Informant Interview LLDA Laguna Lake Development Authority LGU Local Government Unit MBRLC Mindanao Baptist Rural Life Center MBSCPL Mount Banahaw - San Cristobal Protected Landscape NCCAP National Climate Change Action Plan NIA National Irrigation Administration NIS National Irrigation System NWRC National Water Research Centre NGO Non-Government Organization OSA Original Service Area PAGASA Philippine Atmospheric, Geophysical and Astronomical Service Administration PAMB Protected Area Management Bureau STW Shallow Tube Well SALT Sloping Agricultural Land Technology SFR Small Farm Reservoir SWIP Small Water Impoundment SCRIS Sta. Cruz River Irrigation System CGMCM3 Third Generation Coupled Global Climate Model UPLB University of the Philippines Los Baños

TABLE OF CONTENTS Page List of Acronyms i Table of Contents ii List of Tables iv List of Figures v ABSTRACT vi INTRODUCTION 1 Background of the Study 1 1.1. Objectives of the Study 3 Location and territorial coverage of the Study Area 3 METHODOLOGY 5 RESULTS AND DISCUSSION 5 The hydrology and water resources of the Sta. Cruz Watershed 5 Topography and land use features 5 Climate and rainfall 7 River systems and Springs 8 Groundwater 9 Utilization of water supply from the watershed 10 Manifestations of climate change in the study area 12 Potential impacts of climate change to water resources and crop production 14 Flooding and sedimentation 14 Water scarcity 16 Landslide 18 Water quality degradation 18 Threats to ensuring food security 19 Water adaptation strategies and technologies 22 Protect and enhance the watershed’s capacity to nurture its water 22 resources Improve the performance of existing irrigation systems 24 Avert the occurrence of landslide 25 Control water quality degradation 25

Factor climate change in the planning, design and rehabilitation of water 26 resources project Improve the generation and sharing of climate and hydrological 26 information

Policy issues and governance 27

SUMMARY AND CONCLUSION 28 POLICY RECOMMENDATIONS 30 REFERENCES 32

iii

LIST OF TABLES

No. Title Page 1 Municipalities covered by the Sta. Cruz Sub-Watershed 4 2 Elevation-Area relationship of the Sta. Cruz Sub-Watershed 6 3 Area per slope range of the Sta. Cruz Sub-Watershed 6 4 Land Use Change within the Sta. Cruz Watershed from 1993 to 2014 6 5 Average monthly rainfall and number of rainy days in Sta. Cruz and Nagcarlan, 7 Laguna 6 Major rivers passing each municipality within the Sta. Cruz Watershed 9 7 Groundwater data of some municipalities within or near the Sta. Cruz Sub- 9 Watershed 8 National Irrigation systems (NIS) serving farms within the Sta. Cruz Sub 11 Watershed 9 Communal Irrigation Systems (CIS) abstracting water from the Sta. Cruz Sub- 11 Watershed

10 Destructive typhoons that affected Laguna area from 2004 – 2006 12 11 Percent deviation of the 2004 – 2012 monthly rainfall from the 1994 – 2003 period 13 12 Percent deviation of the 2004 – 2012 maximum daily rainfall per month from the 13 1994 – 2003 period

LIST OF FIGURES No. Title Page 1 Spring water storage tank in Barangay Bukal, Nagcarlan 16 2 The present SCRIS Diversion Dam 17 3 A garbage-filled irrigation canal in San Pablo Sur, Sta. Cruz 19

ABSTRACT

This study aimed to explain the water and food security-environment interactions in a dynamic setting brought about by climate change focusing on the Sta.Cruz wateshed with the end goal of identifying water adaptation measures and policy recommendations to minimize the adverse effects of climate change and improve the welfare of communities. Based on available secondary information, focused group discussions, key-person intereviews and field ocular inspections, an indicative assessment was made on the watershed’s water resources conditions and water supply utilization, manifestation of climate change and potential impacts of climate change on water resources and crop production. Findings indicate that while the level of rice self-sufficiency of communities within the watershed are below 50 %, and that there are manifestations of pronounced rainfall variability as well as apparent reductions in the output of water supply sources, it appears in general, that the impacts of previous strong typhoons to their means of livelihood are not so serious or permanent to deny them the capacity to restore agricultural productivity within resonable period or acquire food from other sources. There are indications, however, that if the present rate of deforestation and non-sustainable agricultural production pracitices are not effectively controled in the near future, frequent occurrences of more extremely strong typhoons and habagats will cause more serious and probably permanent damages to their agricultural production systems through more intense and persistent flooding, sedimentation and significant decrease in the output of water supply sources. Averting such grim scenario includes the following “no-regrets” adaptation measures: protection and enhancement of the watershed’s capacity to nurture its water resources through protection and reforestation of declared forest reservation or protected areas and promotion of sustainable agriculture mainly through enforcement of conservation farming tchnologies in sloping agricultural lands; improvement in the performance of existing irrigation systems; foctoring climate change in the planning, design, and rehablitation of water resources projects; and improvement in the generation and sharing of climate and hydrologic information. For the effective and timely implementation of the above measures, the LGUs, being mandated as fronline agencies for addressing issues on climate change, should undergo more intensive “education” on climate change for them to be able to pass needed relevant reoulutions and executive orders. Policy and institutional concerns would include the following: strengthening the river councils; promote and support the implementation of the existing Mout Banahaw-San Cristobal Protected Landscape; policies to encourage adoption of soil and water conservation technologies; economic/finacial schems for farmers to cope with impacts of climate change- related events; olicies and programs on livelihood to improve household resilience.

Key words: climate change, wateshed, water resources, rice self-sufficiency, typhoons, habagats, protected areas, conservation farming, hydrologic information

WATER ADAPTATION STRATEGIES AND AGRICULTURAL PRODUCTIVITY UNDER CHANGING CLIMATE

Manolo G. Villano, Dulce D. Elazegui, Precious R. Zara, Raem Dominic S. Brion and Agnes C. Rola

I. INTRODUCTION

1.1. Background of the Study Agriculture remains the country’s backbone for the sustainable attainment of food security. This sector is greatly vulnerable to climate change especially due to the increase occurrences of El Nino Southern Oscillation (ENSO) and La Nina events, bringing drought and extreme rainfalls, respectively. Agriculture, being strongly dependent on water resources and climatic conditions, and crop production, being extremely sensitive to large year-to-year weather fluctuations, will greatly affect the country’s production and have a domino effect on our food self- sufficiency (NCCAP, 2011). With a nationwide average annual rainfall of about 2,400 mm, water is not supposed to be a problem in the Philippines. Unfortunately, such rainfall is not uniformly distributed with respect to time and space throughout the country; thus, limiting its direct availability for agriculture. As such, some farms in the country can plant rice and other crops at least two times a year just depending on rainfall but others can only plant once unless waters from springs, rivers, lakes, and underground could be tapped through irrigation systems. In the hydrologic cycle, it is precipitation or rainfall that feeds or recharges our common water supply sources such as the springs, rivers, lakes and groundwater through the watersheds. But considering their generally degraded conditions, our watersheds’ capacity to detain and absorb rainfall to recharge their aquifers are drastically reduced resulting in decreasing water supply from the springs, rivers and groundwater. Consequently too, most of the rainfall moves down as runoff causing soil erosion, landslides, sedimentation, and flooding problems as the country often experiences during strong typhoons. The magnitude of these problems will be aggravated if the intensity and frequency of strong typhoons and droughts will be worsened by climate change thereby causing more problems to the food security of the country. Indeed, there is a need to readjust our normal criteria of analyzing and managing our climate and water resources in relation to agricultural development to factor in the threat of more intense and more frequent hydrologic extreme events. And due to the differences in

1Professor, College of Engineering and Agro-Industrial Technology, UP Los Baños 2University Researcher, College of Public Affairs and Development, UP Los Baños 1 3 Research Assistant, CIDS 4 Professor, College of Public Affairs and Development, UP Los Baños geographic location and in land features, each region, province, or municipality or even barangays may experience different climatic hazards and differ as well in levels of vulnerability. As such, the effectiveness of a climate change adaptive measure may also differ from one locality to the other. Within a watershed, resources are shared and trans-boundary impacts from upstream to downstream, from one local government unit to another are likely to happen. Sustainability of the watershed resources therefore requires sustainable environment and natural resources management programs through an effective policy and governance system. It should address the following dimensions: how resources are shared – access, rights to use; how responsibilities are distributed/shared to protect/conserve/sustain resources; and how benefits, risks and burdens are shared/allocated (Gupta and Lebel, 2010). This paper attempts to explore issues on food security and water in a watershed context with particular focus on the Sta. Cruz watershed, part of theLaguna de Bay Sub-basin in the province of Laguna. Food security has been defined as “having enough to eat now and the assurance of having enough in the future” (Christian and Greger, 1991) or “having reasonable confidence that food needs will be met regularly” (Commoner, 1985). The focus of the paper is in line with the strategic priority programs of the National Climate Change Action Plan (NCCAP). These seven priorities include: food security, water sufficiency, ecosystems and environment stability, human security, climate-smart industries and services, sustainable energy, and knowledge and capacity development. As per Climate Change Act of 2009 (RA 9729), the national government ordains the LGUs as frontline agencies for addressing issues on climate change. Critical therefore is the adequacy of appropriate policies at the local levels and the institutional linkages among LGUs in food security and climate change programs at watershed level. It is thus important to understand the issue of climate change and its potential threat to the welfare of their communities.

1.2. Objectives of the Study

The general objective of this study is to explain the water and food security- environment interactions in a dynamic setting brought about by climate change focusingon the Sta.Cruz wateshed. The end goal is to be able to formulate strategies and policy recommendations to minimize their adverse impacts on the well-being of people within the watershed or on those depending on its natural resources for livelihood. This project seeks to answer the following questions: a. How do the changes in climate affect the water resources and food security among inhabitants dependent on the life support of the watershed in general and among the three types of communities under study in particular? b. What water adaptation measures may be undertaken to minimize the adverse effects of these interactions on the welfare of communities? c. What policies may be recommended to minimize these adverse effects and improve well-being of communities?

1.2. Location and territorial coverage of the Study Area The Province of Laguna is situated within the Southern part of Luzon in the Philippines. Its capital town, Sta. Cruz, is close to 87 kilometer road distance from Metro-Manila via Calamba City and could be reached by car in about 2 two hours or less. Situated on the southeastern part of Laguna de Bay as seen in Figure 2, the Sta. Cruz watershed lies between 140 2’47”N to 140 18’21” N and 1210 21’18” E to 1210 29’32” E. As shown in Table 1, the watershed has an approximate area of 14,858 ha which covers the whole or a portion of the municipalities of Lumban, Sta. Cruz, Pagsanjan, Pila, Magdalena, Majayjay, Liliw, Nagcarlan, San Pablo, and Rizal in Laguna and the municipality of Lucban in Quezon. About 141 barangays are within or partly within the watershed. On its southwestern lies is the Mt. San Cristobal while on its eastern side is the Pagsanjan Sub-Watershed. Both watersheds are along the northern slopes of Mt. Banahaw.

Table 1. Municipalities covered by the Sta. Cruz sub-watershed basin. Municipality Number of Area (ha) % of total Population % of total Barangays sub-basin sub-basin Covered area population Liliw 33 3600.31 24.64 32,469 17.64 Lucban 1 75.17 0.11 Lumban 1 63.83 0.44 Magdalena 15 1325.29 9.07 8,248 4.48 Majayjay 7 264.18 1.81 654 0.35 Nagcarlan 45 5260.36 36.00 48,101 26.14 Pagsanjan 4 559.94 3.83 8,359 4.54 Pila 1 70.54 0.48 171 0.09 Rizal 10 909.26 6.22 9,762 5.30 San Pablo 3 197.82 1.35 2,678 1.45 Sta. Cruz 21 2284.30 15.63 73,550 39.97 Total 141 14611.00 100.00 183,992 100.00

II. METHODOLOGY

To address the above objectives, the following activities were undertaken: a) assessment of the water resources status of the Sta. Cruz Watershed and its sufficiency to meet the demands of present and future users considering the possible effects of climate change; b) assessment of how appropriate water supply from the watershed is being managed by users; c) identification of water adaptation strategies and technologies appropriate for the study area; and, d) review existing policies and institutional linkages in the watershed. Data were obtained from both secondary and primary sources. Secondary information were obtained from published and unpublished literatures, profiles and comprehensive land use plans (CLUP) of municipalities within the Sta. Cruz Watershed, and documents provided by the National Irrigation Administration (NIA) of Region IV-A in Pila, Laguna. Primary data were collected through focused group discussions (FGD) and key informant interviews (KI)in the sample barangays within the watershed. Ocular inspections of some relevant sites were also undertaken.

III. RESULTS AND DISCUSSION

A. The hydrology and water resources of the watershed 1. Topographic and land use features Factors affecting the vulnerability of water supply from a watershed include topography, soils, and land uses or land cover. The Sta. Cruz Sub-Watershed and the adjacent Pagsanjan Sub-Watershed are located on the northern side of Mount Banahaw. From the topographic map, land elevations within the Sta. Cruz Watershed ranges from near zero on the lake shore to more than 1,400 Meters near the top of Mount Banahaw. The highest peak of Mount Banahaw is 2,160 meters. Table 2 shows that about 20.4 % of the total watershed area is within low elevation, 56.7 % at medium elevation, while 22.9 % on high elevation. Based on the slope map (Table 3), about 73.9 % of the watershed area is with less 18 % slope, 23.7 % is within 18 to 50 % slope, and just 3.4 % has slope greater than 50 %. In terms of land use and cover, Table 4 shows that forest and grassland areas decreased between 1993 and 2014 by about 59 % and 16 %, respectively. On the other hand, agriculture and built-up areas increased by close to 33% and 13%, respectively (Tiburan, et al., 2014).

Table 2. Elevation- area relationship of the Sta. Cruz Sub-watershed.

Percent of total Description Elevation (masl)* Area (ha) (%)

Low ≤ 20 3,026.44 20.37 Medium 21 – 470 8,427.78 56.73 High > 470 3,402.14 22.90 * masl = meters above mean sea level.

Table 3. Area per indicated slope ranges for the Sta. Cruz Sub-Watershed.

Slope range Area per slope range Cumulative area (%) (ha) % (ha) % 0 – 3 1,726.19 11.69 1,726.19 11.69 3 – 8 4,349.69 29.46 6,075.88 41.15 8 – 18 4,832.01 32.73 10,907.89 73.88 18 – 30 1,974.63 13.37 12,882.52 87.25 30 – 50 1,386.55 9.39 14,269.07 96.65 > 50 495.27 3.35 14,764.34 100 Total 14,764.34 100 - -

Table 4. Land Use Change within the Sta. Cruz Watershed from 1993 to 2014. (Adapted from Tiburan Jr., et al, 2014)

Land Use/ 1993 2014 Difference* Cover Area (ha) % of total Area (ha) % of total ha %

Forest 4,907.27 33.03 1,995.51 13.43 - 2,911.76 -59.34

Grassland 1,371.96 9.23 1,151.37 7.75 - 220.59 - 16.08

Agriculture** 5,828.00 39.22 7,761.12 52.28 + 1,939.12 + 33.27

Built-up 2,576.10 17.34 2,915.41 19.62 + 339.31 + 13.17

Others*** 174.81 1.18 1,028.73 6.92 - 88.92

Total 14,858.14 100.00 14,858.14 100.00 * Negative sign (-) means a decrease from 1993 to 2014; Positive (+) means an increase. ** Agriculture = land area occupied by Annual crops + land area planted with perennial crops *** Others = Water area + Cloud / shadow noise

2. Climate and rainfall Based on the Corona Climate classification method, most areas on the South Western portion of the Sta. Cruz watershed are under Type III which resembles Type I. That is, the seasons are not very pronounced but with short dry season. This is somewhat confirmed by the rainfall data of Nagcarlan (Table 5)which shows that only three months (February to April) are considered dry (Corona classifies a month as dry if its average monthly rainfall is less than 50 mm). Based on FGDs, the high-elevated barangays of Nagcarlan specifically, Barangay Bukal and San Francisco usually do not experience dry months, enabling the plating of vegetables two times a year. Indeed, the number of rainy days throughout the year (Table 5) supports this observation. The southeastern areas of the watershed are also classified as Type IV resembling Type II climate since rainfall is more or less evenly distributed throughout the year with no dry season.

Table 5. Average monthly rainfall and number of rainy days for Sta. Cruz and Nagcarlan, Laguna.

Month Average rainfall (mm) Average number of rainy days Sta. Cruza Nagcarlanb Sta. Cruzc Nagcarland

January 47.6 57.7 4.1 10.4 February 28.8 31.1 2.6 7.0 March 40.3 17.2 2.9 4.8 April 40.8 41.1 2.3 7.2 May 112.1 193.6 5.5 14.4 June 179.1 226.3 8.5 18.9 July 214.4 353.9 10.3 24.4 August 191.1 365.1 8.5 18.9 September 183.7 397.5 9.3 20.1 October 195.3 251.2 9.3 18.8 November 219.6 231.4 9.1 18.2 December 143.4 129.6 7.3 14.4 ANNUAL 1,596.1 2,297.0 79.7 176.9 a/, c/ Average for 19 years (1994-2003), computed from daily rainfall from PAGASA b/, d/ Source: Nagcarlan 2009 CLUP (Length of record not specified)

The climate of the low-elevated barangays of the watershed is quite different as manifested by the 19-year (1994 to 2012) average monthly rainfall of the PAGASA Weather Station in Sta. Cruz, Laguna (Table 5). Using the Corona method, it could be observed that on the average there four dry months from January to April and eight wet months from June to December.

3. River systems and Springs The Sta. Cruz Watershed, one of the 24 sub-basins of the Laguna Lake, is endowed with numerous rivers, springs and groundwater. Sta. Cruz River is the main stream of the Sta. Cruz Watershed and the other major tributaries are listed in Table 6.Unfortunately, the discharge or stream flow rates of most of these rivers are not currently being measured. There may be some measurements being done by some agencies but they are yet to be published for public use. The DPWH used to measure discharge rate of the Sta. Cruz River at the SCRIS Diversion Dam in Barangay Calumpang, but for some reason it was discontinued. Subjecting the DPWH data from 1950 to 1977 to flow-duration analysis and reciprocal method, NWRC (1983) estimated the spatial 80% dependable stream flow of the Sta. Cruz River Watershed to range from 12 to 15lps/sq km. At the SCRIS Diversion Dam (drainage area is 10,300 ha), this amounts to about 1,200 to 1,500 lps dependable flow. The 80 % dependable stream flow may be used to estimate the potential farm area to be irrigated by a river. There also several springs within the Sta. Cruz Watershed which are the main sources of domestic water supply of high-elevated barangays. In the Municipality of Liliw for instance, several barangays are getting their domestic water supply from 15 springs. Shown in Figures 5 is a storage tank for water from a spring few meters above. According to the farmer who guided the project survey team, the spring used to be a source of domestic water supply for some households in the Barangay but now no more water is coming from the spring especially during the summer months. Almost all households are now depending on a water supply pipe abstracting water from another spring quite far from the Poblacion.

Table 6. Major rivers passing each municipality within the Sta. Cruz Watershed.

Municipality Bodies of water Catchment Area (ha) Liliw Liliw River 55.4627 Bungkol River Mamalin River Lapad River Aoy River Magdalena Maimpez River 3,450 Nagcarlan Nagcarlan River Rio Bunga River Talahibing River Rizal Mayto River May-it River Lake Calibato Springs mentioned (no name) Sta. Cruz Sta. Cruz River 14,858

(Data sources: CLUPs of Municipality)

4. Groundwater Based on a rapid ground water supply assessment made by the NWRC (1982), the flood plain portions of Sta. Cruz are classified as shallow well areas where the static water level is generally within six meters below grown surface and that the depth of wells constructed is normally not more than 20 meters. Most of the areas up to the mountains are deep well or difficult areas in terms of abstracting groundwater through wells.. The groundwater properties of observed wells in the different municipalities within the Sta. Cruz Sub-Watershed is given in Table 7 below.

Table 7. Groundwater data of municipalities with land area within or nearby the Sta. Cruz Watershed.

Municipality Number Average Average Average of wells Well Normal Specific observed Depth SWL Capacity (m) (m) (lps/m) Sta. Cruz 101 37 3.47 0.81 Pagsanjan 11 37 4.35 0.86 Pila 7 34 1.29 0.4 Victoria 11 57 2.61 0.96 Liliw 6 30 8.34 NA Magdalena 6 23 11.38 NA Nagcarlan 13 18 7.08 0.51 Rizal 1 62 36.59 NA (Source: NWRC, 1983)

B. Utilization of water supply from the watershed Waters abstracted from the Sta. Cruz Watershed are being used for the following major purposes: domestic, irrigation, power generation, and recreation particularly resorts with swimming facilities. Except for the mini hydro-power plant which uses water flow from rivers, all the other users either get water from the rivers, springs, or groundwater. In the hydro-power plants, water is diverted from the river and used to run the turbines after which the water is returned back to the downstream section of the river with insignificant losses. The water being used in swimming pools are also returned back to the river with minimal reduction in quantity and quality if chlorine is not used. In the medium to high elevated communities (e.g., Barangays Bukal and San Francisco of Nagcarlan; Bungkol of Liliw) domestic water supplies are generally from springs either developed by the community or by water districts. For the low-elevation communities such as Patimbao and San Pablo Sur of Sta. Cruz, most sources of domestic water are from deep tube wells operated by water districts. Approximately, close to 80 % of the water being abstracted from the watershed is devoted to agriculture through irrigation. Tables 8 and 9 list down the irrigation systems abstracting water from the Sta. Cruz Watershed. The Sta. Cruz River Irrigation System (SCRIS) is the lone National Irrigation System (NIS) abstracting water from the watershed for irrigation. At present, it is irrigating about 2,160 hectares benefiting around 1,577 farmers. However, not all farms irrigated by the system are within the Sta. Cruz Watershed area. Some farms in Pila and considerable rice farms in Victoria are also irrigated by the SCRIS. On the other hand, the Balanac River Irrigation System (BRIS) draws water from the adjacent Pagsanjan Watershed but irrigates some rice farms in San Pablo Sur and San Pablo Norte which are within the Sta. Cruz Watershed. In addition to the NIS irrigated area, around 400 hectares of rice farms listed in Table 9 are being served by the ten communal irrigation systems (CIS) also abstracting water from the watershed. These are constructed with the assistance of NIA but totally managed by the farmers.

Table 8. National Irrigation Systems (NIS) serving rice farms within the Project area. (Computed from NIA data, Pila, Laguna)

Original Ave. area irrigated NIS Municipality served Service 2011-2014 System Area (ha) Dry Wet 1. SCRIS 3,100 Liliw, Nagcarlan, Sta. 948.47 950.67 Div. I (FUSA= Cruz, Pila, Victoria Div. II 2,160) 1,030.19 1,005.31

1,978.66 1,955.97 Total area irrigated (ha)

63.46 63.10 Ave. % CI based on OSA Ave. annual % CI based on OSA 126.56

91.60 90.55 Ave. % CI based on FUSA Ave. annual % CI based on FUSA 182.15 2. BRIS Magdalena, Lumban, Sta. 1,056 878.50 859.28 Cruz, Pagsanjan (FUSA=1,000) Ave. % CI based on FUSA 83.19 81.37 Ave. annual % CI based on FUSA 164.56 Notes: a) CI = Cropping intensity b) FUSA = Firmed-up Service Area

Table 9. Communal Irrigation Systems abstracting water from the Sta. Cruz Sub-watershed. (Data from NIA, Pila, Laguna)

Ave. Cropping Ave. Yield Municipalities FUSA CIS System Intensity (%) a/ (tons/ha) Served (ha) a/ Dry Wet Annual 1.Arjona CIS Liliw 34 2.Bungkol CIS Liliw 63 3.Calumpang CIS Liliw 26 4.Masikap (Cabuyiw, Liliw 44 Palina) CIS 5.Maimpez CIS Magdalena 97 6.Maravilla CIS Magdalena 40 7.Palayan CIS Nagcarlan 28 8.Taytay (Not in NIA’s Nagcarlan 42 list) 9.Tala CIS Rizal 24 10. Talaga CIS Rizal 12 Total 410 Notes: a/ No data for cropping intensity and yield

From the CLUPs of municipalities within the Sta. Cruz Sub-watershed, rice yield level ranges from 3.9 to 5.75 tons/ha or an average of 4.83 tons/ha. Potential yield of traditional varieties may range from 6 to 7 tons/ha. Using the firmed-up service areas, the average annual cropping intensity of the SCRIS and BRIS are 182.15 % and 164.56 %, respectively. Based

11 on the FGDs and KIIs, however, some farmers on the downstream sections of both NIS are claiming that irrigation water do not normally reach their farm during the dry season. Thus the irrigated areas being reported by NIA personnel should be field-validated to have a more accurate estimate of rice production in the area. C. Manifestations of rainfall variability in the study area Pronounced climate variability in the Philippines may be gleaned from the experienced and recorded occurrences of strong typhoons, southwest monsoons, and El Niño phenomenon. From 1972 to 2003, not less than nine (9) El Niño episodes affected the country most notable was that of 1997-98 with more than 9 months of very warm period. Then in 1994 onwards, the passage of destructive typhoons in the Province of Laguna seems to be more frequent as seen in Table 10. The more recent ones are Typhoon Mirinae (Santi) in 2010 and Typhoon Rammasun (Glenda) which directly hit Quezon and Laguna in July, 2014. Analyzing the 19-year (1994 to 2012) rainfall data of Sta. Cruz, Laguna, there appears to be marked variations in the average monthly rainfall and maximum daily rainfall per month between the 10-year period of 1994-2003 to the 9-year period from 2004 to 2012 as shown in Tables 11 and 12. The percent variations indicate that the deviation ranges from a decrease of 13.5 % in July to an increase of 447.3 % in April with an annual increase of 36.0 %. In the case of maximum daily rainfall per month, there was a decrease in the months of March and July but for the other months, the percent increase is from 2.3 % to 177.5 %. The annual increase is 42.5%.

Table 10. Destructive typhoons that affected Laguna area, 2004-2006.

Population Properties Damaged Total Cost Name Affected (In Million Pesos) (In Million Year Family Persons Agriculture Infrastructure Pesos)

TY Yoyong 2004 1,665 6,748 2005 150 750 ITCZ and LPA TY Caloy 2006 517 2,589 111 111 (Chanchu) TS Florita 2006 .160 .16 (Bilis) TY Milenyo 2006 59,810 335,415 597 160 757 (Xangsane) TY Reming 2006 930 4,156 16 8 24 (Durian) Source: Office of Civil Defense-Department of National Defense

Table 11. Percent deviation of 2004-2012 monthly rainfall from the 1994-2003 period.

Average monthly rainfall(mm) Month Percent deviation 1994-2003 2004-2012 January 38.45 63.74 65.77 February 11.90 45.62 283.36

March 31.60 49.06 55.25

April 13.92 76.18 447.27 May 103.43 147.81 42.91

June 145.46 212.80 46.29

July 229.96 198.83 -13.54

August 159.34 222.83 39.85

September 166.65 200.72 20.44

October 175.06 233.01 33.10 November 196.47 242.63 23.49

December 105.66 181.11 71.41

Total 1377.90 1874.34 36.03

Table 12. Percent deviation of 2004-2012 maximum daily rainfall per month from the 1994-2003 period.

Max. daily rainfall per month(mm) Month Percent deviation 1994-2003 2004-2012 January 51.6 52.8 2.33 February 27.2 54.7 101.10 March 94.8 56.6 -40.30 April 28.9 80.2 177.51 May 80.2 92.2 14.96 June 53.2 136.2 156.02 July 116.2 96.6 -16.87 August 106.4 164.4 54.51 September 85.9 119.4 39.00 October 102.6 152.4 48.54 November 101.6 164.6 62.01 December 61.5 127 106.50

Total 910.1 1297.1 705.31

Based on 50-year rainfall data at the PAGASA-UPLB Agro-meteorological Station in Los Baños, Laguna, and using the Third Generation Coupled Global Climate Model (CGMCM3), Combalicer (2014) made simulation and projections of rainfall under two scenarios in the Province of Laguna. The results indicate that in general, precipitation will increase from present (2001- 2010) to the 2080 period.

The above information indicates that in the study area there was a marked difference in the rainfall magnitudes between the last two decades. As to whether these magnitudes of variability could be considered as indicators of climate change may depend on its further deviations and long-term consistency in the future. Nonetheless, it could serve as a tool in increasing the knowledge of the local executives and community people on the meaning and risk of climate change. D. Potential impacts of climate change on water resources and crop production Climate change will decrease the return period (more frequency of occurrence) of certain hydrologic events rainfall and runoff or flood water. Or, for a given return period, there will be an increase in the magnitude of a certain hydrologic event. Plotting the maximum daily rainfall per year of Sta. Cruz, Laguna to a Log-Probability graphing paper, the return period of a maximum daily rainfall of 120 mm is 10 years during the 10-yr period from 1994-2003, while the same magnitude has a return period of just two years during the 9-yr period from 2004- 2012. And for a 15-yr return period, the maximum daily rainfall is 125 mm in the 1994-2003 and 180 mm for the 2004-2012 period. There is no available stream flow data of Sta. Cruz for analysis but it is expected to behave similarly albeit of different magnitude. Historical records of damages to agriculture, local people’s experiences and rainfall data analysis all indicate that the more dominant climate hazards affecting the Sta. Cruz Watershed and the nearby communities benefiting from its natural resources are the increasing frequency and of strong or super typhoons and the Southwest Monsoon (habagat). Besides causing direct physical damages to crops, forest trees, fruit trees, animals and building, super strong winds, very intense rainfall intensity and long duration of rainfall contribute to the occurrence of severe floods, sedimentation, water pollution, and water supply scarcity. To identify adaptation measures appropriate to the area, the vulnerability and occurrence of impacts in the study area are briefly discussed below.

1. Flooding and sedimentation High rainfall intensity and rainfall erosivity are associated with strong typhoons and intense “Habagat”. The rainfall behavior in Nagcarlan indicates increasing rainfall intensity and erosivity in the study area. When forest trees are cut or logged and the land is converted to agriculture without conservation measures as observed in Bukal, Nagcarlan and in Loquin, Liliw, the soil is exposed to the erosive power of the rainfall. If the rainfall intensity exceeds the soil infiltration capacity, runoff occurs causing more detachment and transport of soil particle. The erosivity of runoff is further magnified by increase in land slope. Severe erosion

removes the fertile top soil reducing its crop productivity and exposes the soil layer with less infiltration capacity thereby more fraction of the rainfall occurs as surface runoff. And without trees and vegetation to restrain the movement of water on sloping land, the increased runoff travels faster reaching the low-elevation at a shorter time and causing rivers and canals to overflow resulting to flooding. Some of the eroded soil particles are carried by the runoff as sediment downstream. Streambank erosion is also a potential source of sediments which could be easily carried downstream by high river flows. The damage to the diversion dam of the Sta. Cruz River Irrigation (SCRIS) brought about by Typhoon Milenyo in 2006 was due in part to heavy volume of sediments entrained from the stretch of the river beds by the strong water flow. The new diversion dam (Figure 1) constructed few meters above the previous location in 2007 is already filled up with sediments carried by heavy river flow due to Typhoons Ondoy and Santi in 2010. The intake channels of the Calumpang CIS and Bungkol CIS were also blocked by big rock boulders brought down by very strong river flow high during Typhoon Santi I 2010 As discussed earlier, the land area of the Sta. Cruz Watershed considered as forest decreased from 33 % (4,907.3 ha) in 1993 to 13.4 % (1,995.5 ha) in 2012, while the area devoted to agriculture increased from 39.2 % (5,828 ha) in 1993 t0 52.3 % (7,761 ha). Considering that about 60 % of the watershed area has slopes greater than 8 % and that in general, conservation farming is not being practiced in the area, it not unlikely that the severity of flooding and sediment problems in the study area will be will be further aggravated by climate change.

Figure 1. The present SCRIS Diversion Dam

2. Water Scarcity Based on the FGDs and KIIs, drought due to long dry season is not so common in the study area. This is confirmed by rainfall analysis presented earlier which shows that the average number of dry months is four in Sta. Cruz (low elevation) and three in Nagcarlan (high elevation). There is also an increase in the amount of dependable rainfall from the 1994-2003 period to the 2004-2012 period. There is, however, a possibility that the occurrence of a number of El Nino Phenomenon in the 1994-2003 period may recur in the future. A more serious potential impact on water sustainability will be the further reduction in the recharge of the aquifers if the present rate of deforestation is not seriously and adequately arrested. As pointed out above, with deforested watershed coupled with increasing area of non- sustainable practices of farming, occurrence of strong typhoons and intense habagat will cause severe and widespread soil erosion removing the top soil and decreasing the soil infiltration rate. With less soil infiltration, more of the rainfall will move as surface runoff and less will percolate to recharge the aquifers underground. Such situation will eventually lead to reduced water out from springs, decreased dependable river flow, and drop in the groundwater table especially during the dry months thereby affecting the availability and adequacy of water supply for the different uses.

The above situation partly explains the observation in Barangay Bukal, Nagcarlan that a spring (Figure 2) below their “kaingin” area dries up during summer time. While there is no reported drying up of most of the springs supplying domestic water to majority of the upland communities, there are reports during the FGDs that the summer discharges of such springs show significant reductions. Consequently, the same situation is also the major reason why both the Sta. Cruz River System and the Balanac River Irrigation System could not irrigate considerable portion of their service area during the dry season. Significant fraction of the summer flows of the streams are coming from the accumulated water outputs from the springs. The FGDs also revealed that in the earlier decades when much of the watershed is still forested, the water flow of the Sta. Cruz River used to be sufficient even during the dry months. While no historical stream flow record of the river could be used to ascertain such claim, the decrease in the irrigable area of the Sta. Cruz River Irrigation System from 3,725 ha in 1977 to 2,160 ha in 2012 (based on interview with Engr. Virgilio M. Yorro of NIA in Pila, Laguna) may be in part due to decrease in the dependable flow of the river overtime. And as mentioned earlier, significant fraction of the system’s tail-end service area is not being reached by irrigation water during the dry months.

Figure 2. Spring water storage tank in Barangay Bukal, Nagcarlan

3. Landslide The potential threat of landslide should not be disregarded in the formulation of hazard mitigation and adaptive measures. Some portions of the watersheds are of highly steep slopes (>30 % slopes) making them highly vulnerable to landslides under extremely intense and long duration rainfall most especially if such extreme rainfall event is preceded by an earthquake similar in intensity to those that occurred in Bohol in 2013 and in Baguio in 1991. The development of deep gullies which may start with severe soil erosion and formation of rills may cause landslide once the gully head reaches the base of steep side of mountains. Uncontrolled scouring of riverbanks due to extreme peak river flow during super typhoons or intense habagat is another initiation of landslide.

4. Water quality degradation Eroded soil particles brought down the streams by runoff is the main potential source of sediments degrading the physical quality of water. Waste materials like plastics from indiscriminate garbage disposal, residential and commercial areas carried by surface runoff and irrigation water as observed in Barangay San Pablo Sur of Sta. Cruz (Figure 3) is another one. Possible sources of chemical and biological contaminants include fertilizer and pesticides residues from agricultural areas, existing waste water treatment plants / tanks of poultry and piggery businesses and even household septic tanks which abound along the banks of the watershed stream networks. These structures could be reached and washed out by extremely strong and overflowing runoff. This will then further add to the influx of contaminated water in downstream communities and to the Laguna Lake.

Figure 3. Garbage-filled irrigation canal in San Pablo Sur, Sta. Cruz

5. Threats to ensuring food security

Crop production vulnerability according to elevation The vulnerability of a community’s agricultural production systems to strong and intense habagat varies with respect to their relative location within the watershed. In high elevation (more > 470 masl) communities like Barangays Bukal and San Francisco in Nagcarlan, Garcia et al., (2014) reported that the main agricultural products are vegetables (tomato, radish, beans, cucumber, cabbage, cassava, sweet potato, chayote, and mustard). Perennial crops such as lanzones and rambutan were also observed which are usually planted under coconut. Typhoon especially if accompanied by strong winds can cause lodging in vegetable crops and felling of perennial crops like lanzones, coconut palms, and banana. Perennial crops like coconut and lanzones can withstand strong winds but considerable yield reduction is observed. Recovery period of perennial crops may take 2 to3 years. Rejuvenation of felled trees requires additional cost and causes delay in fruit bearing Typhoon especially if accompanied by strong winds can cause lodging in vegetable crops and felling of perennial crops like lanzones, coconut palms, and banana. Perennial crops like coconut and lanzones can withstand strong winds but considerable yield reduction is observed. Recovery period of

19 perennial crops may take 2 to3 years. Rejuvenation of felled trees requires additional cost and causes delay in fruit bearing (Garcia et al., (2014). According to Garcia et al., (2014), the farmers in the medium elevation areas (21 – 470 masl) grow diverse crops. They grow crops that are adapted and grown in both the low and high elevation areas. The major crops planted include rice, vegetables, fruit trees, banana and coconut). Except for rice, the other crops grown in high elevation areas are also grown in the medium elevation areas, hence, they have similar sensitivities to the climate hazards. Irrigated farms within the mid-elevation areas like Barangays Bungkol, and Calumpang of Liliw with CIS, are also threatened by strong typhoons or intense habagats. With inadequate intake gate control structures, extremely high river flow could damage the canals or add much water to the farms causing lodging of rice or even collapse of rice terraces. Sediments and rock boulders may also destroy their diversion structures. As mentioned earlier in this paper, the intake canals of the Bungkol and Calumpang CIS were blocked by big boulders due to Typhoon Santi obstructing water entry to the irrigable farms thereby disrupting rice production. Low-elevation barangays such as Patimbao and San Pablo Sur of Sta. Cruz which are mainly irrigated rice producing areas with small with small portion planted with coconut and fruit trees. Garcia et al., (2014) noted that around 90% of the respondents in both barangays are planting rice. Strong typhoons or intense habagat normally inundates rice plants causing them to lodge be submerged resulting to heavy production losses. Garcia, et al (2014) noted that during a focus group discussion, the farmers estimated a reduction in the yield of around 51-100% in Bgy. San Pablo Sur and 30% in Bgy. Patimbao. Rice self-sufficiency level

With rice as the main staple food in the country, food security may be equated to having enough rice to meet the requirements of the growing population. Using the results of the Survey on Food Demand for Agriculture Commodities, NIA estimated the rice self-sufficiency in the Province of Laguna as follows: 27.44% in 2007; 29.71% in 2008; and 23.63% in 2009. For the communities within the Sta. Cruz Sub-watershed, however, rice self-sufficiency level was estimated to be 46.44 % for 2013. This was based on the following data and assumptions: population of 184,000; estimated rice farm area within the sub-watershed of 1,900 ha (assuming about 70 % of SCRIS FUSA is within the watershed plus CIS FUSA indicated in Tables 8 and 9); average annual cropping intensity at 180 % (based on FUSA); BAS per capita rice consumption of 116 kg/yr; and 60 % milling recovery. While this is quite a conservative estimate (due to some doubts on the accuracy of reported actually irrigated area), this is an

indication that in 2013 the irrigated farms produced only less than half of the rice requirements of communities within the sub-watershed of Sta. Cruz. That is, more than 50 % of the rice requirements within the Sta. Cruz Sub-watershed is coming from outside sources.

Vulnerability of existing irrigation systems

With the potential threat of climate change, the productivity of the existing irrigation systems could be drastically reduced through infra-structure damages by extreme floods and sediments as what Typhoon Milenyo did to the SCRIS diversion dam in 2006. Further reduction in the dependable flow of river feeding these irrigation systems will soon follow if degradation of the watershed will go on unabated by the combination of highly erosive rain and runoff coupled with the current non-sustainable farming and watershed product utilization.

It was pointed out above that the irrigation systems (servicing a total area of about 2,570 hectares) abstracting water from the Sta. Cruz Watershed are not performing well. Based on its original or design service area, the average cropping intensity of SCRIS during the dry season 63.5 % and only 63.1 % in the wet season (Table 8). That means the irrigation system could not supply water to about 47 % of its design service area in both cropping seasons. The major reasons for the low dry season cropping intensity include significant reduction in the dry season flow of the Sta. Cruz River and the inability of the system management in controlling over irrigation by upstream farmers thus denying the downstream farmers of their fair share to the water. On the other hand, damages to planted rice crops due severe flooding during the rainy days is the main culprit for the low wet season performance of the system.

Based on FGDs, farmers also claimed that when the SCRIS diversion dam was severely damaged by Typhoon Milenyo in 2006, the system was in-operational for about two cropping seasons to give way for its reconstruction. The tremendous river flow brought about by high intensity and prolonged rainfall carried down volumes of sediment including big boulders caused the collapsed and washing out of the dam structures. Uncontrolled quarrying along the river bed and sides was also cited as contributing to the weakening of the dam foundation.

E. Water adaptation strategies and technologies

For the specific case of the Sta. Cruz Sub-Watershed and the communities benefiting from its natural resources, super typhoons and intense and long-duration southwest monsoons or habagat are the climate change hazards identified by representative communities and residents to have greater impacts on their lives, livelihood (specifically agriculture), and to the environment in general as discussed above. Presented below are technologies and strategies which could help the community in the mitigation or adaptation to the occurrence of severe flooding, sedimentation, and water scarcity.

1. Protect and enhance the watershed’s capacity to nurture its water resources The capacity of the watershed to absorb and store rain water in its aquifers is dependent on a number of factors which include the following: kind, extent, and density of vegetation; soil properties affecting its infiltration and percolation rates; topography; and, geology. The first three factors determine the amount of rain water which could be added to the aquifer, while geology dictates the amount of water which the aquifer could store and released by gravity. Of these factors, it is only geology which could not be practically influenced by man. The rest could be affected in varying degrees by man’s activities. The following techniques /practices/strategies could help the watershed enhance its capacity to store rain water thereby conserving water and at the same time reduce flood waters in the downstream communities.

a. Protection and reforestation of declared forest reservation or protected areas  Identify and delineate the portion of the Sta. Cruz Sub-Watershed which is within the Mount Banahaw-San Cristobal Protected Landscape (MBSCPL) which was officially declared on December 11, 2009 as a full pledge Protected Area under Republic Act No. 9847. It covers an area of 11,133.30 hectares within the political jurisdiction of the Provinces of Laguna and Quezon. The same area has been declared in 1921 as a national park.  Support and pursue effective implementation of the MBSCPL Master Plan being implemented by the Protected Area Management Bureau of the (PAMB) of the DENR. The Plan envisions that by year 2020, the protected area will be a “sacred and unique place rich in biodiversity, energy, food, fresh air, water and livelihood cared for by the community in a balanced manner based on history

and sustainability for the benefit of many generations to be showcased to the world”. The Plan should focus on the promotion of sustainable livelihood within the community level.  Give priority concern on the protection of the remaining 2,000 hectares of forest cover within the watershed even if these are not within the Protected Area.  Delineate also the 1,150 hectares grassland within the watershed and consider the feasibility of pursuing its reforestation under existing programs such as the Community-Based Forest Management and National Greening programs of the government.  Besides planting of trees, study the need and feasibility of the following measures in both the forested and grassland areas: gully check dams and plugs; stream bank stabilization; and artificial aquifer recharge pits b. Promote sustainable agriculture  Subdivide the 7,760 hectares (52 % of the watershed area) being used for agriculture into micro-watersheds or catchments for a community and catchment-based resources development and management. A good starting point will be the catchments of the CIS within the watershed.  Develop and implement conservation farm plan with the community people.  Consider the feasibility of catchment-wide promotion of the following soil and water conservation (SWC) technologies/practices in the upland agricultural lands (field testing and demonstration farms may be established prior to widespread promotion):

- Sloping Agricultural Land Technologies (SALT) – the strategy of using tree legumes to control soil erosion and improve the fertility and stability of sloping agricultural lands. It is a low-cost method of upland farming developed by the Mindanao Baptist Rural Life Center (MBRLC) based in Bansalan, Davao del Sur. These are briefly defined below.

. SALT-1→a form of alley farming in which field and perennial crops are grown in bands 4 – 5 meters wide between contoured rows of rows of leguminous trees and shrubs. The trees are thickly planted in double rows to form hedgerows.

. SALT-2 → Sloping Agro-Livestock Technology. A goat-based agro-forestry project with land use comprising 40 % agriculture, 20 % forestry, and 40 % livestock . SALT-3 → Sustainable Agroforestry Land Technology. A small-scale reforestration technology with 40 % farm area devoted to agriculture and 60 % forestry . SALT-4 → Small Agro-fruit Livelihood Technology. A system of planting fruit trees and short-term crops at a ratio of 75 %:25 % Note: All variants utilize shrubs and tree legumes in contour hedgerows.

- Promote conservation practices such as contour cultivation and planting; crop diversification; multiple cropping; contour hedgerows; agro-forestry system; conservation tillage; Terraces (bench terrace, “eyebrow” terrace, etc); slopeland wind breaks; - Promote alternative water management technologies such as rainwater harvesting; Runoff impoundment ponds such as Small farm reservoir (SFR) and Small Water Impoundment (SWIP); - Monitor and maintain irrigation systems - Check dams along gullies/tributaries of streams; Gully check dams and plugs; Runoff diversion ditch; Hillside ditch; Grass waterways; Stone ditches and walls; Stream bank stabilization (e.g. use of “gabions”); Artificial recharge pits

2. Improve the performance of existing irrigation systems

The following mitigating and adaptive measures may help in improving the performance and sustainability of the irrigation systems and to avoid disruption of rice production in the area:

 Promote and support the implementation of appropriate measures and strategies for the protection and enhancement of the watershed’s capacity to nurture its water resources as presented above. Such measures as explained above will help recharge the aquifers thus increasing the summer flow of the Sta. Cruz River. They will also contribute in modulating the volume of flood waters and

in delaying the arrival of flush floods in the flood plains. These will eventually contribute in increasing both dry and wet season cropping intensities of the irrigation system. This shows the interrelationships between communities on the upstream part of the watershed to the downstream communities in terms of runoff behavior and water resource availability and adequacy. Thus, the manner by which upland communities manage the upper portion of the watershed will either be a boon or a bane to the lowland communities. Hence the merit for a watershed-based, interdisciplinary, and comprehensive approach in the development and management of natural resources particularly water.  Consider the appropriateness and promotion of tested on-farm water management technologies when irrigation water is limiting or when there is too much water. The “Alternate Wetting and Drying” technology is one of them.  Installation of more shallow tube wells (STW) to farms at the tail-end of the SCRIS and BRIS which frequently experience irrigation water shortages during the dry season cropping. This is one of the coping measures being practiced by farmers in San Pablo Sur, Sta. Cruz which is at the tail-end of the BRIS. The tail-end farms of the SCRIS and BRIS are fortunately within shallow well areas.

3. Avert the possible occurrence of landslides  Stabilization of critical river banks by means of “Ripraps” or “Gabions” is the first and immediate defense. The long-term and sustainable measures, however, are the strategies discussed above for the protection and enhancement of the watershed’s capacity to nurture its water resources. Such measures will help minimize the volume of runoff hence the swelling of rivers and help control the formation of gullies.

4. Control water quality degradation  Immediate measures to control surface water degradation would be the strict enforcement of existing laws/ordinances on the proper treatment and disposal of waste and garbage. Disposal of garbage on or near creeks and rivers should not be allowed as this could be easily be entrained by flash floods. Existing waste treatment plants near river banks should be relocated to higher grounds which could not be reached by extremely high river flow.

 Reduction of chemical contaminants from agricultural areas could be achieved by strictly enforcing existing protocols for their use.

5. Factor climate change in the planning, design and rehabilitation of water resources project  Climate change will decrease the return period (more frequency of occurrence) of certain hydrologic events rainfall and runoff or flood water. Or, for a given return period, there will be an increase in the magnitude of a certain hydrologic event. Indeed, there is a need for re-computations in the design peak runoff and dependable rainfall to be used in conducting feasibility studies, planning, design, and management of new irrigation systems and rehabilitation of existing systems. The same should be done for flood protection dikes and in soil and water conservation structures. In an interview at the ANC Channel last November 7, 2014, incumbent DPWH Secretary Rogelio Singson suggested that about 20% additional cost of structures such bridges and schools may be added to take care of possible effect of climate change.

6. Improve the Generation and Sharing of Climatic and Hydrological Information  Sound management of the water resources nurtured by the Sta. Cruz Watershed is dependent to a great extent on long-term climate and hydrologic data from monitoring networks within and nearby the watershed. In addition to the PAGASA Weather station in Sta. Cruz, another one weather station should be installed in the upstream part of the watershed probably in Nagcarlan. There appears to be no stream flow gaging station along the Sta. Cruz River at present. Government agencies including GOCCs should be transparent in terms of basic information needed for a better management and policy formulation.  Better access to information, and transparency of its use, for more rational decision-making. As most decisions on water would have to be made at the basin and local levels, accurate, consistent, timely and relevant information about water and climate needs to be widely available. Information and knowledge for local adaptation must be improved and considered a public good to be shared at all levels. Better information, communication and public awareness – reinforced by the right incentives and sanctions – are required to

produce changes in the behavior of water users and consumers” (UN Water Policy Brief ).

F. Policy Issues and Governance

The successful implementation of the identified adaptation measures is highly dependent on the adequacy of appropriate policies and effective governance.

The influence of social and political factors, i.e., social relations/processes, capabilities, power and interest cannot be ignored. In the case of the Sta. Cruz sub-watershed/basin, the challenge is organizing stakeholders to contribute resources for the protection and conservation of the watershed resources (e.g., Laguna de Bay) for its sustainability both from an operational and policy perspective.

Emerging issues

The Sta. Cruz Sub-Watershed is one of the 21 sub-watersheds of the Laguna de Bay Basin. In the policy making and regulatory arena, the Laguna Lake Development Authority (LLDA) is the primary institution that exercises policy, regulatory and developmental functions covering the entire lake and its watershed. Based on a review of the LLDA-related policies and programs, reports and CLUPs of LGUs with land area inside the Sta. Cruz Sub-Watershed, and key-informant interviews, the issues arising in relation to sub-watershed governance system include the following:

 Based on the delineation of watershed boundary, the Sta. Cruz sub-watershed does not cover the whole area of municipalities (e.g., portions of Majayjay and Magdalena lie within Pagsanjan sub-watershed). This complicates comprehensive watershed planning of LGUs)  No explicit policies and programs on sub-watershed scale, usually at LGU level

- Each LGU (municipality has its own policies and programs on food security. e.g., Sta. Cruz and Rizal have Food Security component in their CLUP;

- Each LGU (municipality has its own policies and programs on climate change but not expressly from food security perspective. e.g., Nagcarlan and Rizal have mainstreamed climate change adaptation in plans and programs

- Climate change-related actions were in compliance with national policies, e.g. Climate Change Act and Disaster Risk Reduction and Management (DRRM) Act. This includes putting up Municipal DRRM Office; installation of rain gauge

 Limited institutional arrangement among LGUs on food security and climate change programs at sub-watershed level.

 MOA usually with government agencies such as DA-RFU, DENR. (One case involving Majayjay, Nagcarlan, Liliw; municipalities tried to address the issue of cutting coconut trees but not resolved.  Nagcarlan has linkages with NGOs on sustainable farming practices

 Agriculture programs and projects focus on farmers’ training, seed distribution

 Watershed conservation program generally focused on tree planting

 Municipal ordinance usually on solid waste management, tree planting and deforestation

IV. SUMMARY AND CONCLUSION

Agriculture remains to be the country’s backbone for sustainable attainment of food security. This study aimed to explain the water and food security-environment interactions in a dynamic setting brought by climate change; focusing on the Sta.Cruz wateshed with the end goal of identifying water adaptation measures and policy recommendations to minimize the adverse effects of climate change and improve the welfare of communities. Based on available secondary information, focused group discussions, key-person intereviews and field ocular inspections, an indicative assessment was made on the watershed’s water resources conditions and water supply utilization, manifestation of climate change and potential impacts of climate change on water resources and crop production. Water adaptation strategies and technologies to minimize the potential impacts of climate change were identified including policy recommendations for their implementation.

The average annual rainfall in Nagcarlan, a high-elevation barabgay, is 2,297 mm, while that in Sta. Cruz (low-elevation) is 1,596 mm. Nation-wide, it is about 2,400 mm. The watershed is endowed with several springs, rivers, and moderate good aquifers in the flood plains. Springs are the main sources of domestic water supply in the mid and high elevation

communities. Rivers supply irrigation water to CIS in the mid elevation and to NIS in the low elevation farms. In addition, some farms in the flood plains abstract irrigation water from grownwater through shallow tube wells. Deep wells are the major source of domestic water supply in the low elevation communities. Roughly, close to 80 % of the water abstracted from the Sta./ Cruz Sub-watershed goes to agriculture through the irrigation systems (CIS, NIS and STWs). NIA data and farmers’ complain indicate that these systems, in general, are not irrigating their original design service area due to decreasing dependable flows of the rivers and inefficient use of irrigation water.

Based on historical records of climate-related damages to agricultural, local people’s experiences and rainfall data analysis, the more dominant climate hazards affecting the study area are the increasing frequency of strong typhoons and intense Southwest Monsoon or habagat. Such claim was somewhat validated by simple analysis of the 19-year (1994 – 2012) rainfall data from the PAGASA Wether Station in Sta. Cruz, Laguna. The results show pronounced increase in the average monthly rainfall for the last nine years (2004 – 2014) compared withthe previous decade (1994 -2003). Plotting the maximum daily rainfall per year a Log-Probability graphing paper, the return period of a given maximum daily rainfall decreases from 10 years in the previous decade to just two years in the last decade. And for a given return period, the expected maximum daily rainfall is higher in the last decade by about 24%. These could be an initial quantification of climate change impacts on the water sector.

With the generally degraded conditions of the Sta. Cruz Sub-watershed and the non- sustainable farming practices, extremely high rainfall intensity could cause severe and widespread soil erosion resulting to not only decreasing the productivity of the lands, but to more runoff and sedimentation problems. This will also result to reduced recharge of the aquifers which eventually lead to water scarcity affecting crop productivity. Based on the present performance of existing irrigation systems, the estimated rice self-sufficiency level of communities within the watershed is 46.45 % in 2013. With the expected threat of extreme climatic events to the existing irrigation systems, however, there is very little assurance of having enough rice supply in the market any time of the year.

Averting such grim scenario includes the following “no-regrets” adaptation measures: protection and enhancement of the watershed’s capacity to nurture its water resources through protection and reforestation of declared forest reservation or protected areas and promotion of sustainable agriculture mainly through enforcement of conservation farming technologies in

29 sloping agricultural lands; improvement in the performance of existing irrigation systems; factoring climate change in the planning, design, and rehablitation of water resources projects; and improvement in the generation and sharing of climate and hydrologic information.

For the effective and timely implementation of the above measures, the LGUs, being mandated as fronline agencies for addressing issues on climate change, should undergo more intensive “education” on climate change for them to be able to pass needed relevant resolutions and executive orders. Policy and institutional concerns would include the following: strengthening the river councils; promote and support the implementation of the existing Mout Banahaw-San Cristobal Protected Landscape; policies to encourage adoption of soil and water conservation technologies; economic/finacial schems for farmers to cope with impacts of climate change-related events; policies and programs on livelihood to improve household resilience.

V. POLICY RECOMMENDATIONS

Improving the system of governance at sub-watershed level with consideration for shielding food security from impacts of climate change should take the following policy and institutional concerns into consideration:

 A massive educational campaign on the issue of climate change starting with the Sangguniang Pambayan and concerned units of the province then to the municipalities and barangays. The Sangguniang Pambayan could now pass needed resolutions and the Governor to issue executive orders for the adoption of policies and strategies, their institutionalization, and the provision of financial resources to strengthen the municipalities against the impacts of climate change.  Strengthening the river council, e.g., capacity building, financial autonomy for conflict management, integrated watershed management.  Fast track creation of DRRM office and integrate/institutionalize climate change adaptation/DRRM planning at the watershed level and address trans-boundary impacts climate-related risks and other disasters  . Enhancing institutional partnerships /institution building – public-private partnership, sub-watershed conference/summit  Stricter enforcement of regulatory system on development activities in the watershed

 Formulating/enhancing policies on soil and water governance in responding to food security and livelihoods and climate change adaptation  Support the implementation of the MBSCPL Master Plan being coordinated by the PAMB of the DENR  Policies to promote better/improved agricultural drought/flood management - cropping patterns and crop varieties suited to drought/flood conditions, early warning system  Economic/financial schemes for farmers to cope with impacts of climate change- related events  Policies and programs on livelihood to improve household resilience/food security  Policies to make available to the public basic information such as climate and hydrologic data gathered through the use of government funds, and for the LGUs to require private entities monitoring climate and hydrologic data in their political jurisdiction to provide them with such data.

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