Flexibility key to tackling climate change issue in Cuu Long (Mekong) Delta

Long-term vision and short-term planning should be the twin planks on which the Cuu Long (Mekong) Delta should base its adaptation to climate change, Dutch experts said at a workshop yesterday.

It would be unwise to make big investments in impact mitigating projects like dykes when the actual phenomena could not be predicted with high accuracy, they said.

The two-day workshop, titled "Towards a Mekong Delta Plan", brought together policy-makers and hundreds of experts from the two countries in the presence of Dutch Crown Prince Williem-Alexander, who has been on an official visit to the country.

Workshop participants discussed different options to optimise plans for the Delta relating to many areas including the predicted rise in sea levels, salinity intrusion, drought, insufficient supply of fresh water, agricultural and aquaculture production as well as urban development.

Various scenarios and solutions were discussed based on a "design table" application developed by the Dutch. The design table presented three-dimensional images of the Delta that changed in response to different input data.

The design table session was an interactive spatial planning exercise that sought to help key Vietnamese decision makers "map out scenarios for the future of the Mekong Delta in relation to climate change adaptation," organisers said.

The Dutch side gave a design table to their Vietnamese counterparts at the workshop as a present.

"In the long term, many things will remain unclear," said Prof L. O. Fresco of the University of Amsterdam.

"We do not know by how much the sea levels will rise and water discharge will increase," she told Viet Nam News.

So planners for the Delta should take a step-by-step approach, she recommended.

"It would be wasteful to spend a lot of money to build expensive dykes if sea levels do not rise as much as predicted," she said.

"Sometimes we cannot change things back," she added.

Speaking to Viet Nam News on the sidelines of the workshop, deputy minister of Agriculture and Rural Development Dao Xuan Hoc said the step-by-step approach was a good idea.

It would allow authorities to have updated statistics on hand to develop the most accurate and appropriate plans, he added.

"We should have a vision for the next 50 years, then we get back to where we are now to develop strategies for every five years," he said.

Hoc also remarked that the Dutch approach to climate change was "strong" compared to the Vietnamese, which he felt was "more moderate."

He explained, "For generations, people in the Delta have adapted to rather than avoided floods."

Nguyen Ngoc Anh, dean of the Southern Institute of Water Resources Planning, said that it was not a sustainable option to drain all the floodwaters from the Delta's rivers to protect rice crops.

"Intensive farming leads to high accumulation of fertilisers and pesticides that need to be flushed out by the annual floods," he explained.

On the other hand, rice crops have now been shortened from 90 to just 70 days, allowing farmers ample time to wash their fields with fresh water before sowing a new crop.

"Farmers should be more flexible in timing their crops based on weather forecasts," Anh said.

‘Living with the floods'

According to the institute's flood-management plan, the delta is divided into zones of deep, middle and shallow flooding that sustain one, two and three rice crops within a year.

However, in order to safeguard the delta's big cities, "living with the floods" is not a good choice, given that they can cause huge damage to industrial zones, Hoc said.

"So here, flood control, not regulation, is preferable," he added.

Anh of the Water Resources Planning Institute noted that food security for both the country and the world should be taken into account in formulating and implementing urban development plans.

"The Government requires around 1.8 million hectares for rice crops in the region," he said.

Regarding sea-level rise and salinity intrusion, he felt that sluices should be built at just three, rather than all eight estuaries of Mekong River.

"The Ham Luong, Co Chien and Cung Hau Estuaries together account for 38 per cent of water flow of all Mekong tributaries," he said, "Retention of fresh water in these tributaries will be enough to irrigate a large part of the Delta."

However, the biggest difficulty in climate change planning for the Mekong Delta was to address different, and sometimes conflicting priorities at the same time, said Dr Fresco.

The different functions of water needed to be taken into account, including agriculture, fisheries and ecosystem, she said.

"It's also the same in the Netherlands," she added, noting that Viet Nam could learn from Dutch experience in this regard.

"Ministries have to work together and cannot take one-dimensional solutions," she said.