INOWASIA internship student from NUBB at NUOL on “Application of Physical-Chemical as Indicators to Evaluate Domestic Wastewater Quality in Vientiane City”

My name is Meng Ponleu CHEA. I am a first year master student in sustainable agriculture at the National University of Battambang (NUBB). I appreciate the opportunity to work as an #INOWASIA internship student at the National University of Laos' Center of Excellence in Environment (CoEE, NUOL).

On April 4, 2023, I was grateful that a workshop on water resource management and challenges in Southeast Asia was organized. In the workshop, I opened my mind to the importance of water management.

On April 10th, 2023, we got a small meeting with Dr. Santi for a presentation of my background. After this meeting, Dr. Santi assigned us the following tasks:

  • Find out more information or a paper related to the topic “Biological, Physical, and Chemical Characterization of Wastewater Quality”.
  • Study how to utilize lab machines such as 3MTM PetrifilmTM, BOD, Water Parameter, FT-IR Spectrometer, and others.

In full April, we got to learn from many of the machines in the lab that were guided by Dr. Santi and staff of lab on INOWASIA equipment and other equipment in the lab such as: the refrigerator centrifuge, water purification system, 3M petrifilm count plate, 3M petrifilm count plate reader, BOD BD600, pH meter and water parameters.

On April 20, I went to take a water sample for BOD and 3M. In there, used water parameters to test the water before taking the sample. For this test using dilution 1:1 on 3M with incubation with 35 oc , but for BOD BD600 failed for this first time.

On April 25, I tested 3M plat and 3M plat reader to finding E.coli and total coliform between tap water compare and underground water again that incubation with 35 oc.

On April 27, I went to take water sample for 3M and BOD again, using water parameters to measure environmental variables. At that time, we tried to learn how to defer temperature intubation at 37 oc and 42 oc with dilution 1:1, 1:5 and 1:10 . For BOD, I tried again with no saturation, saturation 30 minutes, 1 hour, 1 hour 30 minutes, and 2 hours. We tried to find method for our research.


Figure 1 Using Water Parameter Outdoor



Figure 2 Calibration Water Parameter


Figure 3 Using 3M Plat Reader


Figure 4 Preparing Sample for BOD Testing


My interested field research during this internship is “Application of Physical-Chemical Indicators to Evaluate Domestic Wastewater Quality in Vientiane City ”. The use of physical and chemical indicators to evaluate domestic wastewater quality can help to ensure that wastewater is treated properly before it is discharged into the environment. The main objective is to quantify physical and chemical variables at each sampling site, investigate water quality in Vientiane city through physicochemical, and compare water quality among sites.



In May, I gained knowledge from several of the lab's equipment, including the UV-IV spectrometer, Hana's water colorimeter, thermoreactor RD 125, photometer MD600, fume hood, turbidimeter and the hydro-bios water sampler ruttner.

On May 5, 2023, I went to collect sample for BOD test and repeatedly did the blank test with DI water. Add 5 drops of nitrification inhibitor and 3 drops of potassium hydroxide solution to 157 ml volume sample.

on May 15, 2023, Testing COD, preparation solution with low COD 150ppm for 4 tubes by diluted from 1.2ml of COD/CSB 0-1500ppm, add 9.12ml of 97% sulfuric acid and 1.68ml of distilled water. For each tube, 1 tube for distilled water is a blank sample, 2 tubes for a water sample, and the last tube for oxytetracycline. Use thermoreactor RD 125 for 2h with 120min after checking low COD with photometer MD600 and UV-IS spectrophotometer XD 7000.


Turbidity, a qualitative property that results from solid particles impeding light transmission through a water sample, is the technical word used to describe a solution's cloudiness. I learned by comparing the data from three machines: a turbidimeter TB211 iR, a UV-IS spectrophotometer XD 7000, and a photometer MD600.

On May 16, 2023, I went to observe the field for the sample site and test it by utilizing the water parameter on the location to obtain samples of HongXeng domestic wastewater for our research. When we return to the lab, we exported data from the water parameter and learn how to use the hydro-bios water sampler ruttner, which takes water for testing in the laboratory on the parameter listed in Table 1.

On May 26, 2023, I collected wastewater samples from five locations in Vientiane City. Before collection, I used a multiparameter water meter and then a hydro-bios water sampler to collect wastewater for physical, chemical, and biological studies in the lab under the supervision of Dr. Santi.

On May 29-30, 2023, Dr. Sati taught and guided me and other internship students in ion chromatography (Eco IC) to detect anion and cation in wastewater samples.

I will analyze the data and draft a manuscript on June.

INOWASIA is an Erasmus + Capacity Building Higher Education project that promotes a joint action of 11 organisations across 5 countries (Cambodia, Laos, Vietnam, France and Spain) to train a new generation of water professionals in Southeast Asia. More info

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This project has been funded with support from the European Commission. This publication reflects the views only of the author, and the Commission cannot be held responsible for any use which may be made of the information contained therein.

Project Number: 619225-EPP-1-2020-1-ES-EPPKA2-CBHE-JP

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