|Extracting groundwater for domestic, agricultural and industrial use might exacerbate natural land subsidence, especially in river deltas, they said. — Photo moitruongnhkb.com
by Gia Loc
CAN THO (VNS) — Water utilities in Viet Nam, particularly in the Mekong Delta, must take pro-active action to safeguard the sustainability of future public water-supply services, as climate change is affecting water production, experts said at an international seminar held in Can Tho this week.
At a three-day seminar that began yesterday, foreign and Vietnamese researchers said that changing precipitation patterns and rising sea levels were increasing the salinity of surface water and groundwater.
Extracting groundwater for domestic, agricultural and industrial use might exacerbate natural land subsidence, especially in river deltas, they said.
To ensure the sustainability of future water supply in the region and especially in the southwest, the Ministry of Construction plans to build two inter-regional water supply plants using surface water sources from the Hau River, said Le Van Tuan, head of Viet Nam Water, general director of Viet Nam Water Sanitation and Environment Joint Stock Company, and lead consultant for the Ministry of Construction.
High investment costs will be needed for the two plants, so economic efficiency will not be high initially, according to Tuan.
"This is a challenge in building the plants," he said.
Le Anh Tuan, vice director of Research Institute for Climate Change under Can Tho University, told Viet Nam News that many methods for sustainable water supply should be carried out in case the plants break down a suspension of water supply occurs.
Moreover, if water sources for the inter-regional water-supply systems come only from the Hau River, long-term sustainable water supply would not be ensured.
If the Hau River's water sources are polluted or the water level falls in the future, the region would lack sufficient water, he added.
Because long water pipelines can easily cause water losses, the best method to use would be artificial aquifer recharge (AR), which is common in many countries.
With AR, natural groundwater supplies are enhanced by using man-made conveyances such as infiltration basins or injection wells, according to the US Environmental Protection Agency.
Tuan said that Vietnamese researchers should seriously consider using the AR method.
Tom Kompier, first secretary for water and climate at the Embassy of the Kingdom of the Netherlands, said the Netherlands was located at the end of a river system in a very fertile plain and has huge agricultural potential, just like Viet Nam's Mekong Delta.
"Climate change is of great concern to us," he said.
Not all of its impacts are negative, but there is ample cause for worry, he said.
The sea-level is rising, weather patterns are shifting, and discharge from the rivers is changing.
"We need to prepare for floods on the one hand and water shortages on the other. I am sure this sounds familiar, because these are major concerns in Viet Nam, too," he said.
The Netherlands focuses on the important relations between water management and the ability to adapt to climate change.
"We know that climate change is happening, we know its direction, but what we don't know is how fast change will be. We also know that dealing with climate change is going to cost a lot of money, but we realise our funds are limited," he added.
"After all, we cannot afford throwing our money to the wind. More than ever, we need to consider what to do and what not to do. And also, we must avoid making choices today that will cause an increasingly heavy financial burden tomorrow, a burden that may ultimately become impossible to bear," he said.
He said the answer would be so-called adaptive delta management which could deal effectively with climate change.
"In the Netherlands, we also have abundant fresh water, but not the entire year. Like Viet Nam, we have problems with subsidence and with increased salinisation," Kompier said.
One innovation to deal with water scarcity is the introduction of service levels, he said.
The national and local government, utilities, and users would discuss what the maximum sustainable level of water supply should be, and practical water use during periods of scarcity, he added.
The seminar is part of a project on climate-change preparedness for public water utilities.
Begun last year, the four-year project is carried out by a partnership of water utilities, provincial governments and academic institutions in Viet Nam and the Netherlands.
VitensEvides International (VEI), a joint venture of the two largest public water utilities of the Netherlands, is the lead partner. — VNS