Author: Dr SAO Davy, Visiting Fellow at CDRI’s Centre for Natural Resources and Environment

Key Messages

• Cambodia experiences a paradox of abundant water resources during wet seasons and severe scarcity in dry seasons, significantly undermining agriculture, infrastructure, and livelihoods. This highlights the critical need for improved water management.
• Despite substantial investments, Cambodia’s centralised and engineering-focused water management has largely overlooked crucial social and environmental aspects, resulting in persistent water shortages for agriculture and a high rate of underperforming or dysfunctional irrigation systems.
• While promoting farmer participation through Farmer Water User Communities (FWUCs) is essential for decentralising water governance, these communities are hindered by insufficient capacity, chronic underfunding for operations and maintenance (O&M), and poor maintenance, which weakens their effectiveness and perpetuates a “build-neglect-rebuild” cycle.
• An integrated strategy is vital for Cambodia’s sustainable water future, focusing on empowering FWUCs, prioritising funding for infrastructure maintenance, encouraging private sector participation, and enhancing the quality of irrigation systems.

Cambodia, a country with stunning scenery and a rich cultural legacy, is endowed with an abundance of water resources. The Mekong River and Tonle Sap Lake, along with numerous other rivers crisscross the country, supporting agriculture, ecosystems, and the livelihoods of millions. With total renewable water resources at 476 km³/year, it is surprisingly that only a mere 0.5 percent (2.18 km³) is utilised annually. Agriculture alone consumes a staggering 94 percent of this withdrawn water, primarily for irrigation (Figure 1).

Despite this abundance, Cambodia faces a significant paradox: severe water scarcity during dry seasons, which cripples agriculture, infrastructure, and livelihoods, while wet seasons bring destructive floods. Floods threaten 80 percent of the population residing along the Mekong and Tonle Sap floodplains, and droughts severely impact 30 percent of farmland, leading to 36 percent crop losses. This highlights a critical need for improved water management.

Figure 1: Water resources availability and water uses in Cambodia

Source: FAO. 2022. AQUASTAT Core Database. Accessed on 17 June 2025.

 

The Unseen Crisis: Underperforming Irrigation Systems

For many, water management in Cambodia is synonymous with irrigation development. In 2024, the country boasted 2,352 irrigation systems (56 large, 1,166 medium, and 1,122 small-scale systems, complemented by 8 large-scale reservoirs) across 25 capitals and provinces. However, the reality on the ground is grim. A vast majority—90 percent—of these systems are either underperforming or completely dysfunctional. This is not just an issue with older, Khmer Rouge-era infrastructure; even newer projects, despite international funding, suffer from poor design, shoddy construction, and inadequate maintenance.

The core problems lie in inadequate design, lack of farm-level distribution systems, and insufficient consideration of crucial factor like crop water requirements, water availability, and hydraulic conditions—the way water flows and behaves within the system. This dysfunction directly impacts farmers, as seen on 21 January 2025, when hundreds of locals and rice farmers in Takeo province protested severe water shortages threatening their dry-season rice crops. Farmer expressed how consistent water scarcity forces them to grow lower-value paddy, severely limiting their economic prospects due to unreliable irrigation.

A Cycle of “Build-Neglect-Rebuild”

Cambodia has made substantial financial commitments to enhancing its irrigation infrastructure. Since the mid-2000s, an estimated USD1.3 billion to USD1.6 billion has been invested in rehabilitating existing schemes and constructing new ones. The current Irrigation and Water Resources Investment Program (2019-2033) further pledges USD2.6 billion to expand irrigation to over 1,375,000 ha of agricultural land.

However, this impressive investment masks a critical flaw: the strategic misallocation of resources. Substantial funds are poured into “development” and “rehabilitation” while the chronic underfunding of operations and maintenance (O&M) persists. This perpetuates a destructive cycle of “build-neglect-rebuild,” where new systems are constructed without adequate O&M budgets, merely adding to the pool of dysfunctional infrastructure. The sheer number of schemes, particularly the 2,288 small and medium-scale systems, exacerbates these O&M challenges. This points to a profound deficiency in quality and long-term sustainability, rather than a lack of infrastructure quantity.

The Governance Gap: Centralisation vs. Farmer Participation

Despite efforts towards decentralisation and farmer participation, water management in Cambodia largely remains centralised and engineering-focused, often overlooking critical social and environmental aspects. Initiatives like Participatory Irrigation Management and Development (PIMD) and Irrigation Management Transfer (IMT) aim to shift O&M responsibilities to Farmer Water User Communities (FWUCs).

Yet, these FWUCs face significant hurdles, including dependence on external support, limited internal capacity, and difficulties in collecting water fees. Funding for O&M is chronically insufficient, with historical government and donor focus on new construction over maintaining existing infrastructure. This underfunding undermines the long-term sustainability of irrigation schemes. Consequently, FWUCs struggle to collect Irrigation Service Fees (ISFs), especially when water supply is unreliable, creating a vicious cycle where a lack of maintenance leads to poor water delivery, making farmers reluctant to pay, which further hinders maintenance.

The private sector’s role is also limited, with Private Water Sellers (PWSs) often acting as de facto managers. However, PWSs operate in a challenging environment marked by limited regulation, unreliable information, significant financial risks, and informal contracts. They also contend with inconsistent water availability, inefficient technology, and difficulties in fee collection.

Towards a Sustainable Water Future

To truly unlock Cambodia’s agricultural potential and build a resilient future for its farmers, an urgent and integrated strategy is vital. This strategy must move beyond the “build-neglect-rebuild” cycle and address the root causes of the water paradox.

Key recommendations include:

• Strengthening FWUCs: Empowering FWUCs with enhanced capacity in water and financial management is crucial for effective decentralised water governance.
• Prioritising O&M Funding: Shifting financial focus from new construction to the sustainable maintenance of existing infrastructure is paramount.
• Fostering Robust Private Sector Participation: Encouraging and regulating private sector involvement in water governance can bring much-needed efficiency and innovation.
• Enhancing Infrastructure Quality and Data Management: Improving design, construction quality, and data management and information systems for irrigation schemes will ensure long-term effectiveness.

By implementing these reforms, Cambodia can move towards a future where its abundant water resources consistently nourish its land and people, transforming challenges into opportunities for sustainable development, particularly in agriculture, climate resilience, and rural livelihoods.