Can Tho promotes low-waste aquaculture to ease environmental pressure

According to the Can Tho Sub-Department of Fisheries and Resources Surveillance, solid waste generated in local aquaculture is quite diverse. Of greatest concern is sludge and organic matter from pond bottoms in intensive, high-density farming models.

Research from the "Strengthening Capacity for Renewable Energy Transition and Waste Management for Sustainable Development in the Mekong Delta" project (Project K1), implemented by the Can Tho Department of Agriculture and Environment in coordination with ActionAid International Viet Nam, found that each intensive shrimp farming cycle generates roughly 123 to 151 tons of pond-bottom sludge per hectare. If not properly collected and treated, this sludge can degrade water quality and increase the risk of disease outbreaks and spread.

In addition, wastewater from farming ponds also creates significant pressure, containing organic matter and nutrients. Discharging it directly into natural canals and streams not only affects water sources but can also impact neighboring farming areas.

Plastic waste, including feed packaging, bags, bottles, ropes, nets, and other materials used during farming, is also difficult to break down.

Do Van Thua, Deputy Director of the Can Tho Sub-Department of Fisheries and Fisheries Resources Surveillance, said current waste treatment methods still have significant limitations. Many small-scale farming households still stir up pond-bottom sludge and discharge it directly into natural rivers and canals, causing organic pollution and facilitating the spread of disease.

In intensive farming areas, particularly high-tech white-leg shrimp farms, conditions are generally better, but the pressure of managing dried sludge waste remains substantial.

Shifting from treatment to prevention

On the sidelines of the workshop "Strengthening Solid Waste Management in Aquaculture in the Mekong Delta," held in Can Tho this week, Quach Thi Thanh Binh, Deputy Director of the Can Tho Department of Agriculture and Environment, said aquaculture waste is an issue requiring growing attention as intensive, semi-intensive, and high-tech farming models continue to expand.

Binh emphasized: "We need to shift from a mindset of treating waste after it is generated to reducing waste generation and reusing it directly within the production process."

With this approach, Can Tho has set a direction for the simultaneous prevention, collection, treatment, and reuse of aquaculture waste.

One solution already underway is the application of on-site waste treatment technology at farming facilities. In 2024, under Project K1, Can Tho implemented 28 models applying biogas systems to treat aquaculture waste. This technology helps break down organic matter in sludge, generating energy and fertilizer while reducing the volume of waste discharged directly into the environment. The models also bring economic benefits, helping farming households cut fuel costs.

The deputy director said the Can Tho Environmental Protection Project for the Fisheries Sector for 2026-2030 identifies the development of waste management models at farming areas and facilities as a key task. Going forward, the city's agriculture and environment sector will focus on four main groups of solutions.

First is encouraging farmers to shift toward low-emission farming models that conserve water and feed and reduce chemical use. Ecological, organic, shrimp-rice, shrimp-forest, fish-rice, and multi-species polyculture models are being developed to suit each ecological zone, and Can Tho has drawn up a plan for developing shrimp-rice farming areas for 2026-2030 in a safe, sustainable, and climate-resilient direction.

The city will also promote science, technology, and digital transformation, applying sensors, IoT, pond monitoring systems, automation, RAS, and biofloc technology to better control pond conditions and limit waste generation.

In addition, the city will strengthen environmental management and monitoring and guide farmers in properly sorting, collecting, and treating waste in line with regulations, a step considered decisive for limiting waste released into the natural environment.

The city will also build a circular value chain in aquaculture, linking breeding stock, feed, farming, harvesting, and processing with the treatment and reuse of by-products.

Can Tho's goal is not only to reduce the volume of waste requiring treatment but also to change how aquaculture waste is viewed. When by-products, sludge, and recyclable materials are put to use, waste from one stage can become input for another, cutting production costs, limiting pollution, raising product value, and increasing income for farmers.