Dead holes often appear in rainy season
At the beginning of April, after several out of season storms, dead holes caused by sudden subsidence have again began to appear in the city, a situation which is likely to worsen when the rainy season begins in earnest.
Dead holes have regularly appeared in the city during the last decade, but this year has been notable for several incidents. The appearance of dead holes has become increasingly frequent following the construction of increasingly larger infrastructure construction, causing a danger to traffic.
According to the data released by the municipal Department of Transport, 64 dead holes were reported in 2010. That number increased to 100 in 2011. At the beginning of 2012, though the monsoon season has yet to start, several dead holes have already appeared.
The latest case happened on the afternoon of April 14 when a dead hole appeared at the Hong Bang-Ngo Quyen crossroads in District 5. In March, another hole appeared on Cach Mang Thang Tam Street in District 3. In February, two holes appeared at the crossroads of Pasteur-Han Thuyen in District 1 and on Ly Thuong Kiet Street in Tan Binh District.
To minimise road subsidence and maintain traffic safety in the city this rainy season, the department has required construction units to strictly supervise construction work.
The department also directed that the supervisory consultative groups were compulsory to be present at construction sites when constructing joints and re-surfacing roads, especially when covering geo-textile and embanking stones around manholes.
The agencies under the department were urged to seriously investigate these problems, ensuring that old infrastructure is not combined with new works, and that local drainage remains unimpeded. The inspections will also ensure that there are sufficiently safe barriers around deep holes and construction firms have been tasked with ensuring that they leave sites entirely safe on finishing.
Also, all construction units were required to quickly check the joints among underground drainage pipes to detect potential leaks or blockages.
Unused underground drainage pipes also need to be checked regularly and secured if necessary. Concrete and cement may be pumped into pipes to ensure road subsidence does not occur.
If construction units and supervisory consultative groups don’t carry out these requirements and later incidents occur, strict sanctions will be applied.