RESEARCH ON THE SCIENTIFIC AND PRACTICAL BASIS TO HARMONISE WATER ALLOCATION WITH WATER TREATMENT FOR IRRIGATION SYSTEMS IN THE RED RIVER DELTA
09:59 - 15/03/2018
Topic: Process of water distribution and water pollution treatment in irrigation systems
Question: Which measures related to water distribution can support clean irrigation water provision in the Bac Hung Hai irrigation system?
The Red River delta has nine large distribution systems drawing water directly from the main river to supply water to various productive sectors and for domestic water supply. These irrigation systems are facing increasing stress due to shortage of water and water pollution. So the challenge for the water-research community is to assess the quantity and quality of supplied water in the each region to ensure harmony of the benefits of water use and limit the impacts of water pollution. The aim of this research is to provide the scientific and practical basis to harmonise water distribution and water pollution treatment in irrigation systems of Red River Delta to solve the problem of water resources division between sectors and ensure water quality in the region.
Urbanisation and industrialisation in the Red River Delta has led to multiple claims on the water resources. At the same time, these two phenomena have increased water pollution so that meet quality criteria to be used. This has severely affected the lives and livelihoods of people, especially the small scale individual household based cultivation and aquaculture. In many irrigation systems, people can no get irrigation water due to high level of pollution. In some cases, the fish in the river have been reported to have been poisoned.
Meanwhile, the water resource management and the irrigation system management bodies do not have the knowledge and information to harmonise water source between sectors and regions on the basis of quality and quantity. To make matters worse, the scope and responsibilities of each agency and organisation are not demarcated clearly, and their respective mechanisms and policies for managing water quality often overlap.
Total water volume, flow regime and the level of water pollution are related to one another and directly affect the economy, environment and people's health. As water flow has an impact on spread and diffusion of pollutants in the entire irrigation system, the available water in a system is used not only for the water supply to meet the water demand in a region, but is also valuable for diluting pollutants in system. Thus water contamination can vary from region to region. In order to assure water quality in regions suffering from heavy contamination, it is crucial to manage the relationship between supply and quality. Especially during the dry season, when water demand risks for all sectors, water availability for reducing the concentration of pollutants declines. Therefore the simulation of quality and quantity of water in irrigation systems is essential to provide a basis for surveillance measures and waste water treatment in each specific region.
In the present status quo, the upstream water-users take advantage of their location and maximise their water consumption while indiscriminately discharging waste at the tail-end. Meanwhile, the downstream water-users are at a disadvantage but are passive in exercising their water rights. The severe scarcity of clean water has given rise to disputes between the local communities and the power generation industry, and between different water use sectors within the irrigation system. Thus it is urgent to find a visual method for sharing, monitoring and management of water resources.
In the Red River Delta, Bac Hung Hai irrigation system is the largest, and exhibits the impact of the above mentioned factors. Therefore it has been chosen as the case study. Like other irrigation systems downstream of the Red River, Bac Hung Hai irrigation system faces many difficulties in getting water supply for the entire system due to drop in the water level in the Red River water level. This is due to the construction of many hydroelectric plants upstream, such as Son La, Hoa Binh and Thac Ba, etc, which store water for power generation, thus the water available downstream. Meanwhile, rapid population growth has led to increasing water demand.
This research will use two methods: fieldwork and hydraulic modelling.
The fieldwork has already begun for collecting hydrographic and hydraulic materials, and for surveying the environment data at the focal positions of irrigation system, measuring the terrain and geomorphic in the main regions of the irrigation system, etc. It is being done in cooperation with the irrigation management companies and local authorities. In addition, consultations with people of the focus areas have been organised to understand how their lives have been affected.
After completing fieldwork, the water demand will be calculated and a hydraulic model for the qualitative and quantitative assessment for entire Bac Hung Hai irrigation system will be built following the discharge scenarios of hydroelectric reservoirs. At the same time, a visual assessment of water pollution between regions within the irrigation system will be carried out.
The research will apply the MIKE 11 model to assess water resources both in quantity and quality for entire Bac Hung Hai irrigation region including the provinces of Hanoi, Bac Ninh, Hai Duong and Hung Yen.
The findings of this research are expected to provide the basis and criteria for sharing water and assessing water quality in the irrigation system. The research will also contribute to the improvement of mechanisms and policies on water management, and will propose new methods for making the irrigation systems of Red River delta adaptable to the major changes in the new period.
Figure 1 - Red river water level at record low in 2010 at location of Long Bien Bridge (Hanoi)
Figure 2 - The black water at the Kenh Cau drain, Yen My district – Hung Yen province
Figure 3 - The water discharged from industrial parks
Figure 4 - Residential rubbish discharge directly into the irrigation system
Figure 5 - Sewage infected with chemicals
Figure 6 - Sewage from the craft villages discharge directly into canals
Figure 7 - Domestic water source is also contaminated due to the pollutants seep into the soil
Figure 8 - Installation of pumping stations to support watering in the dry season
Figure 9 - Survey the water source in some areas of the irrigation system
Figure 10 - Measure water level in the dry season in some locations of water scarcity in irrigation system
Figure 11 - Some images in the process of establishing the model MIKE 11