6.4.2 Water reuse measurement
Srinakharinwirot University (SWU) measures the reuse of water across the university. Water reuse means recycling treated wastewater for beneficial purposes such as landscape irrigation. At Ongkharak Campus, wastewater that flows into the campus water system is treated with microorganisms (bioaugmentation), then pumped from the campus canals and reused for landscape irrigation. The volume of water reused is measured every month and recorded in the University's SDG Sustainability Dashboard. In 2025, the University reused 13,944 m³ of water. This measurement was in place throughout 2025.
How Water Reuse Is Measured
At Ongkharak Campus, treated water from the campus canals is reused for watering trees, shrubs and lawns around the campus. The reused volume is recorded every month as the number of 4 m³ (4,000-litre) water truck trips by the Sustainable Development Division and compiled in the University's SDG Sustainability Dashboard. At Prasarnmit Campus, lawns are irrigated with water pumped from Saen Saeb Canal, but the volume is not yet recorded.
The photographs below show a water truck and the pumping of treated water from the campus water system for tree irrigation at Ongkharak Campus.
Water Reused in 2025
In 2025, the University reused 13,944 m³ of water (3,486 trips), equivalent to 1.5% of total water consumption (909,429 m³). This is more than double the 6,096 m³ reused in 2024, an increase of 129%.
Campus | Source of reused water | Use | Volume (m³) |
Ongkharak Campus | Campus water treated with microorganisms | Tree and landscape irrigation | 13,944 |
Prasarnmit Campus | Water pumped from Saen Saeb Canal | Lawn irrigation (sprinklers) | Not recorded |
Total |
|
| 13,944 |
Monthly Water Reuse at Ongkharak Campus, 2025
Month | Trips (4 m³ each) | Volume (litres) | Volume (m³) |
January 2025 | 250 | 1,000,000 | 1,000 |
February 2025 | 336 | 1,344,000 | 1,344 |
March 2025 | 500 | 2,000,000 | 2,000 |
April 2025 | 440 | 1,760,000 | 1,760 |
May 2025 | 220 | 880,000 | 880 |
June 2025 | 220 | 880,000 | 880 |
July 2025 | 220 | 880,000 | 880 |
August 2025 | 200 | 800,000 | 800 |
September 2025 | 250 | 1,000,000 | 1,000 |
October 2025 | 250 | 1,000,000 | 1,000 |
November 2025 | 200 | 800,000 | 800 |
December 2025 | 400 | 1,600,000 | 1,600 |
Total 2025 | 3,486 | 13,944,000 | 13,944 |
The screenshot below shows the 2025 water reuse record in the University's SDG Sustainability Dashboard, with a total of 13,944 m³ of water reused for tree and landscape irrigation in 2025.
Source: https://script.google.com/macros/s/AKfycby53PzkcT8eUJD9a933GyE_59Tyse0n8TG1QjRJUxyqwEYqK_xBcjTKrLDgHnuEIs7G/exec
Rainwater Harvesting at Ongkharak Campus
Rainwater is also harvested at Ongkharak Campus. The campus lakes, a rainwater retention pond and rainwater storage tanks collect and store runoff. This water is treated with effective microorganisms and pumped for landscape irrigation, reducing the use of tap water (SWU Sustainable University Performance Report, Academic Year 2025, UI GreenMetric evidence WR.2 and WR.3, pp. 156–158).
Source: https://drive.google.com/file/d/1hVGrDvbj9BgNzyuM_Hj4kS-o5aaPH4lJ/view