VietNamNet Bridge - The Department of Transport in HCM City has prepared a plan to minimise the subsidence of road surfaces in order to ensure residents’ safety during the upcoming rainy season.

The plan requires the project management boards and contractors who have undertaken underground and pavement works to ensure they check and maintain quality as well as compliance with set construction procedures.

They should make sure that the works avoid damaging the drainage system.

It also asks experts to be present while construction is happening so that they can observe and make timely adjustments and corrections in the work.

The contractors and project management boards should also make a plan to check and review all drainage systems in order to find out flaws that could affect roads and bridges, the transport department has said.

Traffic management agencies, meanwhile, have also been asked to enhance inspections so that problems in the traffic lighting system are discovered and fixed early.

The department has said that it will be strict in punishing violations.

Last month, a three-hour downpour left behind many holes in the city’s roads, especially at the cross-roads of Vo Van Tan Street and Cach Mang Thang Tam Street in District 1; Le Quy Don Street and Dien Bien Phu Street in District 3; and Le Thanh Ton Street and Ton Duc Thang Street in District 1.

The holes made it difficult and dangerous for commuters to use the roads, eliciting a lot of public complaints.

The HCM City People’s Committee’s flood prevention programme during the 2011-15 period will target eliminating flooding in all inner-city areas as well as parts of other districts.

Flooding in the inner city occurs regularly in areas totalling 100-sq kilometres.

In addition, the plan also calls for reducing flooding in all 6, 11, Tan Phu and Binh Tan districts as well as parts of District 8 and Binh Thanh District.

In the city’s other areas, the programme targets to reduce 70 per cent of flooding caused by rains and 50 per cent of flooding caused by high tides.

The city has set up several measures, including strengthening the implementation progress of flood preventing projects in 2005-2020.

The flood prevention projects include the Nhieu Loc–Thi Nghe Basin Environment and Hygiene Project, the Tan Hoa–Lo Gom Urban Upgrade Project, the building of a dyke along the right bank of the Sai Gon River’s section from Vam Thuat in District 12 to the Provincial Road No. 8 in Cu Chi District, and the building of a dyke along the left bank of the Sai Gon River’s section from Binh Phuoc Bridge to Cau Ngang Canal in Thu Duc District.

In addition, the city will boost preparations for investing in water drainage projects and waste water treatment projects in the city’s south, north, west, southeast and northeast areas.

The city will give priority to granting capital from Official Development Assistance loans for projects related to water drainage, waste water collection, regulation reservoirs, and dykes and sluice gates for controlling high tides.

It will also aim to finish relocating households who have been affected by projects to build dykes, dredge canals to drain water, and finish relocating households who have illegally encroached on canals,sluice gates and water drainage systems.

Ha Noi prepares flood measures

The Ha Noi Water Drainage Company has prepared a flood scenario in preparation for potential flooding in inner Ha Noi during the upcoming rainy season.

The scenario was conduced after the National Centre for Hydro Meteorological Forecasting predicted that this year’s rainy season would come earlier and last longer than in previous years. Heavy downpours began this month and are expected to go on until July.

Director of the company Nguyen Le said the scenario was divided into three likely possibilities according to progressively higher water levels.

Specifically, with less than 50mm of rainfall, Ha Noi would experience little flooding but stagnant water would likely cover low-lying areas. In this case, rescue forces would be on duty to dredge ditches and facilitate water drainage.

With rainfall of between 50 and 100mm, flooding would likely be reported in several key areas. The Yen So Pumping Station, together with Thanh Liet Dam and other stations in Kim Lien Tunnel and Chui Bridge, would operate at full capacity to pump excessive water into Hong River. Mobile pumping forces would be ordered to take duty positions on Thuy Khue, Ngo Quyen and Ton Dan streets.

If rainfall were to exceed 100mm, as many as 23 flooded areas would likely be reported. All available task forces would be mobilised to facilitate city drainage and dams would be opened if necessary.

Deputy director of the municipal Department of Construction Le Van Duc said the city could handle quick drainage if rainfall measured 310mm or less over a two day period.

Last Wednesday, the municipal People’s Committee chairman Nguyen The Thao noted that drainage units must conduct regular checks and improve drains in an effort to curb flooding.

Duty units would be required to work with traffic police and inspectors to assure traffic safety. Relevant ministries and sectors were asked to mobilise capital to construct nine drainage systems worth VND117 billion (US$5.6 million) this year.

Currently, a $350 million Drainage Project for Environmental Improvement is being carried out in Ha Noi. Phase 1 of the project was completed in 2005 which brought the city’s drainage capacity to a maximum of 172mm per two days. The second phase, which kicked off last November, will increase drainage capacity to 310mm over two days.

The project is scheduled for completion by the end of this year.

Source: VNS