Current Assessment and Future Outlook for Water Resources Considering Climate Change and a Population Burst: A Case Study of Ciliwung River, Jakarta City, Indonesia

Abstract

Abstract:Modeling insecurity under future climate change and socio-economic development is indispensable for adaptive planning and sustainable management of water resources. This case study strives to assess the water quality and quantity status for both the present and the near future in the Ciliwung River basin inside the Jakarta Province under different scenarios using population growth with planned additional wastewater management infrastructure by 2030 as mentioned in the local master plan, and comparing the above conditions with the addition of the effects of climate change. Biochemical oxygen demand (BOD), chemical oxygen demand (COD) and nitrate (NO 3 ), the three important indicators of aquatic ecosystem health, were simulated to assess river pollution. Simulation results suggest that water quality in year 2030 will further deteriorate compared to the base year 2000 due to population growth and climate change, even considering the planned wastewater management infrastructure. The magnitude of impact from population growth is far greater than that from climate change. Simulated values of NO 3 , BOD and COD ranged from 6.07 to 13.34 mg/L, 7.65 to 11.41 mg/L, and 20.16 to 51.01 mg/L, respectively. Almost all of the water quality parameters exceeded the safe limit suitable for a healthy aquatic system, especially for the year 2030. The situation of water quality is worse for the downstream sampling location because of the cumulative effect of transport of untreated pollutants coming from upstream, as well as local dumping. This result will be useful for local policy makers and stakeholders involved in the water sector to formulate strategic and adaptive policies and plan for the future. One of the potential policy interventions is to implement a national integrated sewerage and septage management program on a priority basis, considering various factors like population density and growth, and global changes for both short-and long-term measures.

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Sustainable Urban Water Management: Application for Integrated Assessment in Southeast Asia

“…effective precipitation, runoff/infiltration ratio, and head water quality, were used to calibrate different components of the model. A detailed description of the calibration and validation required before obtaining future simulations for different scenarios was provided by Kumar et al [50].…”

Adaptation Strategies for Water Resources: Criteria for Research

“…Kumar et al (2017) face the worsening of water quality which characterizes the most populous and rapidly developing regions, especially the megacities of Asia [14]. This situation is considered due to the overexploitation of groundwater, skewed water supply and demand due to population explosion, and the negative impacts of climate change.…”

“…Only two studies [9,11] identify, propose, discuss, and develop an adaptation scenario. Five other studies [10,14,[16][17][18] belong more properly to the category "Climate change impact studies". The last three studies [24][25][26] analyze changes that have occurred in the climate and with water resources in the recent past decades, without developing any future scenarios.…”

“…The parties affirmed that "adaptation must be addressed with the same priority as mitigation" [1,2]. Under this framework, the COP invited "all Parties to enhance action on adaptation" [1][2][3][4][5][6][7][8][9][10][11][12][13][14] by "planning, prioritizing and implementing adaptation actions, including projects and programs" [1][2][3][4][5][6][7][8][9][10][11][12][13][14]. The Paris agreement (COP21) provided numerous indications and details about adaptation, mainly in Article 7 [2].…”