An activated sludge system has been installed at Myayamon Housing. Pic: Myanmar Water Engineering and Products

HEALTHCARE and waste treatment specialists warned last week that Yangon’s outdated septic system is becoming overloaded as the city’s population increases, resulting in the release of untreated domestic waste into the ground and sewage system.

“Untreated domestic waste contains pathogenic organisms that can cause infectious diseases and skin diseases,” said Dr Khin Maung Swe, the chief medical officer at Asia Royal Cardiac and Medical Care Centre.

Many people in more developed areas of Myanmar use septic tanks for domestic waste. Conventional tanks degrade waste in pre-sedimentation, septic and soak pit zones with the help of microorganisms, which devour any waste with which they come into contact.

Water that enters the soak pit zone is then released into the ground or the local sewage system, depending on how the tanks are installed.

However, experts warn that the waste-devouring properties of the microorganisms in septic tanks were not enough and that wastewater from the soak pit zone should also be chlorinated before it enters the ground or the sewage system.

“In Yangon some septic tanks are overloaded because of population rises during the last few years,” said U Khin Maung Win, the managing director of Myanmar Water Engineering and Products.

“You see two-storey buildings with two families being expanded into eight-storey buildings housing 20 families but the septic system is not upgraded,” he said. “So the septic tank is overloaded and the water in the soak pit zone is too dirty to discard into the sewage system.”

“Moreover, the septic zone is often filled up with excess sludge, which needs to be removed,” he said. “In this case, conventional septic tanks need to be upgraded if there is not enough space to install bigger tanks.”

U Khin Maung Win said the efficiency of a septic tank can be improved by installing an anaerobic biofilter and an activated sludge system, which chlorinates the water.

“Anaerobic biofilters can clean up to 80 percent of the waste and activated sludge systems can clean up to 99pc,” he said.

He said activated sludge systems have been installed in a number of buildings in Myanmar, including Golden Flower Housing Estate, Mogok Meditation Centre, Pan Hlaing Golf Housing Estate, Myayamon Housing Estate, Pyinmana Housing Estate, Asia Royal Cardiac and Medical Care Centre and CBD wastewater treatment plant.

“The owners of these building have taken responsibility for cleaning up the environment by installing these systems. Our actions must not be a burden to the next generation,” U Khin Maung Win said.