To optimize water usage in sanitation facilities, all restrooms across UOK’s new buildings are equipped with dual-flush toilet systems, offering:

• Low flush (liquid waste): approximately 3–4 liters

• Full flush (solid waste): approximately 6 liters

Compared to traditional single-flush systems that use 9–11 liters per flush, this reduces water consumption significantly.
In addition, rainwater harvesting is used for toilet flushing in administrative and academic blocks, helping to conserve potable water. As a result, UOK has achieved a 41.06% reduction in potable water consumption compared to the baseline scenario.
Water pressure is regularly monitored and adjusted using flow meters to ensure efficient flow rates.

To further reduce water usage, low-flow taps with aerators have been installed in washrooms, laboratories, and kitchen areas. These fixtures:

• Regulate water flow without reducing user efficiency

• Mix air with water to reduce volume by up to 50%

• Reduce splash and maintain cleaner, more hygienic sink areas

• Are constructed from corrosion-resistant materials for long-term durability

UOK has significantly reduced potable water usage in building cooling systems through the adoption of VRF (Variable Refrigerant Flow) and split-unit air conditioners, replacing traditional water-cooled chillers. Currently:

• 90% of buildings use air-conditioning systems that require no make-up water

• Less than 10% use high-efficiency water-cooled chillers

• Condensate water collected from AC systems is reused for irrigating vertical greenery, demonstrating circular resource use

To eliminate water wastage from unattended taps and improve hygiene, sensor-based taps and urinal flushing systems have been introduced in several buildings. These systems:

• Dispense water only when hand or motion is detected

• Prevent unnecessary water flow

• Reduce the risk of contamination, which is especially important in post-pandemic environments

UOK has implemented drip irrigation and sprinkler systems for maintaining its landscaped areas. These technologies:

• Deliver water directly to plant root zones

• Minimize evaporation and surface runoff

• Ensure healthy vegetation while reducing overall water usage

Faculty of Medicine has introduced automated dishwashing machines at the canteen to replace traditional manual washing methods. These machines are designed to optimize water usage, using less water per cycle compared to manual washing, while maintaining hygiene standards and improving operational efficiency.

Faculty of Medicine uses water-efficient washing machines for cleaning uniforms, linen, and other institutional textiles. These machines are selected based on low water consumption ratings and short cycle times, ensuring that laundry operations contribute minimally to the overall water footprint.

The University of Kelaniya has implemented a rainwater harvesting system as part of its commitment to sustainable water management. Established on July 28th, 2015, the system consists of six large tanks, each with a capacity of 10,000 liters, providing a total storage capacity of 60,000 liters. During the rainy season, the system collects an average of 750 liters of rainwater per day. This initiative not only contributes to conserving valuable water resources but also serves as an eco-friendly solution for reducing the university's reliance on conventional water supplies, reflecting its broader environmental sustainability 

Per capita water consumption and water usage pattern of  of students who received accommodation facilities in the Yakkaduwe Pannarama Boys Hostel (YPBH) was studied in the year 2017. The water usage by 320 students within a year was 14014 m3 and the student’s per capita consumption of water was 43.8 m3. More than 65% of water was used during bathing while 28% was used in washing purposes. Introduction of basins to wash linen, repairing of leaky taps, installation of water flow rate control devices, harvesting of rain water, reuse of water treated in the sewage treatment plant for gardening purposes and conducting awareness programmes on water conservation for students were suggested as the strategies to reduce water wastage in the University hostels. CSS expects to implement these suggested strategies to reduce water wastage in the university hostels in 2018.