Indonesië – FutureWater

The issue of water scarcity is intensifying across the Asia Pacific region, posing significant challenges for sustainable agricultural production and water resources management. The Water Scarcity Program (WSP), designed by FAO-RAP and partners, aims to bring agricultural water use within sustainable limits and prepare the sector for a productive future with less water. The program aims to assess the ongoing issue of water scarcity in the region, evaluate potential management options, and assist partner countries to implement adaptive management in the agriculture water sector using innovative tools and approaches.

As part of the WSP, FutureWater will design and deliver a two-phase water accounting training program in Indonesia, Vietnam and Thailand, respectively. The first phase of the training will primarily focus on introducing and better understanding the concept of water accounting, its components and approaches. Participants will also work with tools such as REWAS and Follow the Water (developed by FutureWater in collaboration with FAO) to conduct water accounting in agricultural systems at different scales. Through the use of these tools, participants will be able to estimate real water savings at system and basin scale, and also analyze the impact of different irrigation schemes on the overall water availability in the system. The second phase will consist of participants working on the selected basin in each country to develop a detailed water account. Given the data availability and accessibility issues in the region, the participants will learn how to access, process and analyse remotely sensed datasets using Google Earth Engine.

In addition to the trainings, FutureWater will also provide technical inputs for the regional WSP events on water scarcity and highlight the technical challenges of implemeting water accounting and allocation in south-east Asia for the WSP High Level Technical Meeting to be held in June 2024.

Agriculture is the most water demanding and consuming sector, globally responsible for most of the human induced water withdrawals. This abstraction of water is a critical input for agricultural production and plays an important role in food security as irrigated agriculture represents about 20 percent of the total cultivated land while contributing by 40 percent of the total food produced worldwide.

The FAO Regional Office for Asia and the Pacific (FAO-RAP) is concerned about this increase in water use over the last decades that has led to water scarcity in many countries. This trend will continue as the gap between water demand and supply is projected to widen due to factors such as population growth and economic development, and environmental factors such as land degradation and climate change.

Unfortunately, solutions to overcome the current and future water crisis by looking at the agricultural sector are not simple and have often led to unrealistic expectations. Misconceptions and overly simplistic (and often erroneous) views have been flagged and described over the last recent decades. However, uptake of those new insights by decision makers and the irrigation sector itself has been limited.

The “Follow the Water” project will develop a Guidance Document that summarizes those aspects and, more importantly, quantifies the return flows that occurs in irrigated systems. Those return flows are collected from a wide range of experiments and are collected in a database to be used as reference for new and/or rehabilitation irrigation projects.

The FAO/FutureWater project will also develop a simple-to-use tool to track water in irrigated systems using so-called “virtual tracers”. The tool will respond to the demand for a better understanding the role of reuse of water in irrigated agriculture systems. An extensive training package, based on the Guidance and the Tool, is developed as well.

FAO plays an essential role in backstopping the development of the Guidance and the Tool and promoting. FutureWater takes the lead in development of the Guidance, the Tool and the training package. With this, FAO and FutureWater will contribute to a sustainable future of our water resources.

In irrigated agriculture options to save water tend to focus on improved irrigation techniques such as drip and sprinkler irrigation. These irrigation techniques are promoted as legitimate means of increasing water efficiency and “saving water” for other uses (such as domestic use and the environment). However, a growing body of evidence, including a key report by FAO (Perry and Steduto, 2017) shows that in most cases, water “savings” at field scale translate into an increase in water consumption at system and basin scale. Yet despite the growing and irrefutable body of evidence, false “water savings” technologies continue to be promoted, subsidized and implemented as a solution to water scarcity in agriculture.

The goal is to stop false “water savings” technologies to be promoted, subsidized and implemented. To achieve this, it is important to quantify the hydrologic impacts of any new investment or policy in the water sector. Normally, irrigation engineers and planners are trained to look at field scale efficiencies or irrigation system efficiencies at the most. Also, many of the tools used by irrigation engineers are field scale oriented (e.g. FAO AquaCrop model). The serious consequences of these actions are to worsen water scarcity, increase vulnerability to drought, and threaten food security.

There is an urgent need to develop simple and pragmatic tools that can evaluate the impact of field scale crop-water interventions at larger scales (e.g. irrigation systems and basins). Although basin scale hydrological models exist, many of these are either overly complex and unable to be used by practitioners, or not specifically designed for the upscaling from field interventions to basin scale impacts. Moreover, achieving results from the widely-used FAO models such as AquaCrop into a basin-wide impact model is time-consuming, complex and expensive. Therefore, FutureWater developed a simple but robust tool to enhance usability and reach, transparency, transferability in data input and output. The tool is based on proven concepts of water productivity, water accounting and the appropriate water terminology, as promoted by FAO globally (FAO, 2013). Hence, the water use is separated in consumptive use, non-consumptive use, and change in storage.

A complete training package was developed which includes a training manual and an inventory of possible field level interventions. The training manual includes the following aspects:

Introduce and present the real water savings tool
Describe the theory underlying the tool and demonstrating some typical applications
Learn how-to prepare the data required for the tool for your own area of interest
Learn when real water savings occur at system and basin scale with field interventions

The Asian Development Bank is supporting the Government of Indonesia in developing its water infrastructure. Impact of climate change and potential adaptation to those changes are evaluated. One component of the project is to assess water availability for all Indonesian catchments currently and under changing climate. FutureWater has supported the program by developing a climate risk screening approach to rapidly assess current water resource availability and the impact of climate change on this.

Various rapid assessment assessments have been tested and the Turc implementation of the Budyko framework has been proven to be effective for basins in Indonesia. ERA5 past climate and NASA-NEX GDDP climate projections have been applied for all basins in Indonesia. Results show that all Indonesian basins are likely to see an increase in runoff over the coming century. However, variability in runoff will increase, with more extreme dry and wet periods. This will have implications for water management planning and climate related hazards such as more prolonged droughts and higher risks of flooding.

Indonesia is endowed with a full range of both renewable and fossil resources of energy, actively exploited to feed its growing economy. Emphasis has been on fossil, hydroelectric and geothermal resources rather than wind and solar. PLN (Perusahaan Listrik Negara) is the Indonesian State Electricity Company. It is an Indonesian government-owned corporation which has a monopoly on electricity distribution in Indonesia and generates the majority of the country’s electrical power, producing about 175 TWh annually. Only a small fraction of this originates from hydropower.

Indonesia has five large hydropower plants with a capacity over 250 MW: Cirata on Java (1008 MW), Saguling on Java (701 MW), Tangga on Sumatra (317 MW), Sigura-gura on Sumatra (286 MW), and Pamona on Sulawesi (260 MW). The Indonesian government aims to develop more hydropower with quite a strong focus on small and micro hydropower plants.

Capacity of PLN staff to understand the hydrology related to hydropower electricity generation needs to be enhanced. Also, the knowledge of the potential impact of climate change on hydropower requires additional capacity of PLN’s staff. Especially their ability to understand and judge feasibility studies undertaken by external consultants requires upgrading their level of knowledge. Also staffs’ capacity to understand climate risk assessment studies, as today required by most investors, should be further developed.

FutureWater was asked to develop and provide training on those two aspects (hydrology and climate change). Given the huge area of the country and PLN staff working in large distances from each other, it was decided to provide training in a eLearning setting. Initially about 25 staff will be trained and based on lessons learnt the training package will be adjusted to staff needs and further training will be undertaken.

The project should turn this renewable energy opportunity into a source of economic empowerment for the region and a sustainable source of electricity for the people living in North Sumatra. A pre-feasibility study is undertaken to the expected flows at the intake of the proposed Tripa hydro-electric power plant to indicate whether a more detailed feasibility study is feasible.

For the analysis of the expected flow at the intake a hydrological model, called HEC-HMS is used. This hydrological model simulates rainfall-runoff at any point within a watershed given physical characteristics of the watershed. The model is freely available, somewhat less data demanding, and easy to apply. The outputs of the model are analysed by means of streamflow hydrographs, and flow duration curves that serves as a basis for economic feasibility studies to the capacity of the proposed power plants. In addition, flood flows with recurrence intervals up to 10.000 years are analysed.

Emerging markets and low-income countries continue to need large investments in infrastructure to remove constraints on growth; create job opportunities; respond to urbanization pressures; and meet crucial development, inclusion, and environmental goals. In 2009, ADB estimated that an infrastructure investment of $8 trillion would be required during 2010–2020 to maintain current levels of growth in Asia.

Infrastructure for transport and communications, energy generation and transmission, and the supply of water and sanitation are critical for development. These types of infrastructure usually have long service lives, which renders both the region’s existing infrastructure stocks and its future infrastructure investments vulnerable to changes in climate conditions that may take place in the near and medium terms. One of five overarching reasons for concern cited by the fifth assessment report of the Intergovernmental Panel on Climate Change in 2014 was the existence of systemic risks “due to extreme weather events leading to breakdown of infrastructure networks and critical services such as electricity, water supply, and health and emergency services.”

The Technical Assistance study focusses on “building climate change resilience in Asia’s critical infrastructure”. The expected impact of the study is scaled-up support for effective climate change adaptation. The expected outcome of will be an enhanced knowledge base on climate change risks to critical infrastructure in South Asia and Southeast Asia. Specifically, by the end of the study it is expected that Asian Development Bank (ADB) and its Development Member Countries (DMC) will have a fuller understanding of the actions and innovation needed to make critical infrastructure in South Asia and Southeast Asia more resilient to climate change.

The study will focus on 11 countries in South and South-East Asia with three countries in specific: Indonesia, Sri Lanka and Vietnam.

Following the successful development of other hydropower facilities in Indonesia, a new project aims to study the potential of the “Romuku” run-of-river power plant in Central Sulawesi, Indonesia. The project should turn this renewable energy opportunity into a source of economic empowerment for the region and a carbon-emission-free and reliable source of electricity for the people of Sulawesi. A first step is to undertake a pre-Feasibility Study which will result in a go no-go decision for a more detailed Feasibility Study. This study will encompass various components. FutureWater will focus on the hydrological assessment. The objective is to undertake a first order assessment on the expected flow at the inlet of the proposed Romuku run-of-river power plant.

Data for the proposed site are scarce and available data have often missing values. The traditional method of relying on discharge observations to derive the flow duration curve is therefore not possible. As alternative a hydrological rainfall-runoff model can be used to generate discharge data on which flow duration curves can be derived. It is proposed to use HEC-HMS in this pre-feasibility phase. HEC-HMS is a hydrological model that simulates the rainfall-runoff at any point within a watershed given physical characteristics of the watershed. It can be used for studying interventions and for watershed management to determine the effect on the magnitude, quantity, and timing of runoff at points of interest. It is one of the most commonly used rainfall-runoff models, freely available and somewhat less data demanding.

This pre-Feasibility Study will result in a first order assessment of the expected flows into the proposed site location. For the Feasibility Study a more extensive analysis is needed, including more field data, detailed analysis of spatial rainfall patterns, more advanced rainfall-runoff model, advanced calibration of model, and an analysis of potential threats to future water flows (land-use changes, climate change).

The key output of the hydrological study will be a flow-duration curve – critical input for economic feasibility studies of run-of hydropower plant capacity. The area below the curve and the maximum turbine-capacity can be used to asses primary (firm) power and secondary power generation.