The Vientiane Department of Public Works and Transport requested Hungary’s Laoprojekt Zrt. to carry out an assessment of the existing sewer system to prevent flooding during the rainy season at That Luang traffic intersection.
The survey revealed the main reasons for the flooding problems, which are: lack of maintenance, clogging caused by a large amount of garbage from nearby shops and sedimentation caused by the insufficient longitudinal fall.
In addition, the existing pipes size P100, P80, P60 don’t have enough water carrying capacity and have flow direction conflicts so during high-intensity storms the driange system was not able to function properly.
Based on this information, the Water and Environment Engineering State Enterprise has prepared the Cleaning Procedure Documentation, as urgent cleaning and reconstruction has become inevitable in the area.
The cleaning work is only the first step as a quick action, and will be carried out by the Urban Cleaning and Decoration Section. The section has cleaned 45 manholes, 1,600 metres of the existing pipe system and storm drains on the surface between That Luang intersection and That Luang marsh.
The second step, as a long-term solution, will be reconstruction work at That Luang intersection, where the existing sewer system will be modified by removing 456 metres of pipes and 22 manholes, and installing 780 metres of new pipes and 30 manholes in order to resolve the problem of recurring floods.
The cleaning and construction works are being financed by the Hungarian Water Treatment Project.
The project is part of a cooperation between Laos and Hungary for water treatment in Vientiane and has three main parts: the extension of the water treatment plant at Dongbang, and construction of a new wastewater treatment plant and a sewage network under a design and build construct.
The cleaning of the existing sewer system started last weekend and it will last two weeks. In the meantime, the bidding process for the reconstruction work will soon be finished, and a local construction company will carry out the work that is expected to last about four months.
The authorities of Vientiane are confident that after this work is completed, there will be a significant improvement in traffic safety, as the problem of flooding will be reduced. Creating awareness among local residents is crucial for the long-term maintenance of the sewer system. Trash thrown into manholes not just causes clogging in the existing pipe system, but is also heavily polluting the That Luang marsh and the environment.