The Ecological Sanitation (ECOSAN) Pilot Project
In December 2003, the Natural Resources and Environment Board (NREB) and the Majlis Bnadaraya Kuching Selatan or Kuching South City Council (MBKS) with the assistance of DANIDA, Denmark has undertaken a pilot project for an Ecological Sanitation or ECOSAN treatment system at nine terrace houses at Hui Sing Garden in Kuching. The pilot project is the first of its kind in the South East Asia. Chemsain Konsultant Sdn. Bhd. was appointed as the main environmental consultant to spearhead the project from the design stages up to the construction, testing, monitoring of results and regular maintenance of the pilot plant. Wastewater from households in Kuching is only being partly-treated. Black water from toilets undergo a partial treatment in septic tanks before release to the storm water drains. However, this wastewater still contains large amount of organic pollutants and bacteria when released. The grey water from kitchen and bathroom is released to the storm water drains without treatment. The water quality of drains, streams and rivers in Kuching are therefore presently unsatisfactory. Pollution of organic matters may give rise to foul odour and the released bacteria constitute a potential health risk. The biological life of streams and rivers are badly affected by the low water quality. The basic concept of ECOSAN is as follows:
- Separation of black water (toilets) and grey water (sinks and bathrooms)
- Black water collection system utilizing existing, modified septic tanks
- Grey water treatment system consisting of newly-constructed oil and grease tank, pump sump, pre-treatment biofilters and constructed wetland
- The recycling of nutrients, organic matters and water
- Conservation of water is achieved to a higher level
ECOSAN is a cost-efficient mean to achieve significant environment improvements. Black water from the toilets is collected for centralized recycling of energy and nutrients without allowing any overflow into the drains. The grey water is treated locally so that the water released to the storm water drains will meet the highest water quality standards of Malaysia. Wastewater tanks are underground for both the black water and the grey water collections; hence there are no aesthetic problems. As it stands, the entire site where the pilot plant resides has been completely landscaped to allow it to blend into the existing environment. To date, the pilot project has successfully produced very good results for the grey water treated by the biofilters and the constructed wetland.
