16/05/2018
On December 29, 2017, the Ministry of Natural Resources and Environment (MONRE) issued Circular 76/2017/TT-BTNMT regulating the assessment of the assimilative capacity of rivers and lakes (Circular No. 76/2017/TT-MTNMT in order to satisfy the requirements of state management of water resources in the current period. Circular No. 76/2017/TT-BTNMT enacted on 1/3/2015 and replacing the Circular No. 02/2009/TT-BTNMT dated 19/3/2009 regulates the assessment of the assimilative capacity of water bodies (Circular No. 02/2009/TT-BTNMT).
The necessity of the promulgation of Circular No. 76/2017/TT-BTNMT
Law on Water Resources No. 17/2012/QH13 dated 21/6/2012 stipulates that “the identification of assimilative capacity of water sources and the creation of zoning map on the wastewater receiving areas of water bodies” is one of the basic survey activities (Article 12). MONRE is responsible for implementing the baseline survey of water resources (Article 13). Along with that, Law on Environmental Protection No. 55/2014/QH13 dated 23/6/2014 regulates that "survey and assessment of the assimilative capacity of rivers; announcement of river sections and rivers that are no longer capable of receiving wastes” is one of the contents on control and treatment of water pollution in river basins (Article 53 of the Law on Environmental Protection).
On the other hand, Circular No. 02/2009/TT-BTNMT dated 19/3/2009 by the Minister of Natural Resources and Environment has stipulations on the assessment of assimilative capacity of water bodies (Circular No. 02/2009/TT-BTNMT) that were formulated and implemented in accordance with the Law on Water Resources in 1998. In reality, the provisions of Circular No. 02/2009/TT-BTNMT do not have sufficient basis for management of the discharge of wastewater into water bodies according to the Law on Water Resources in 2012. Therefore, it is necessary to amend and supplement the contents of Circular No. 02/2009/TT-BTNMT to be suitable for the descriptions of the Law on Water Resources in 2012, the Law on Environmental Protection in 2014, the current legal documents, as well as the actual situation. The issuance of Circular No. 76/2017/TT-BTNMT has met the requirements of state management of water resources in the current period.
Some provisions of Circular No. 76/2017/TT-BTNMT
According to Circular No. 76/2017/TT-BTNMT, the assessment of the assimilative capacity of rivers and lakes must ensure the principles of river basin and water body-based system. The water bodies such as rivers, streams, channels and canals (rivers) must be divided into river sections for evaluation when the assessment of assimilative capacity is implemented. The segmentation of rivers, identification of water use purposes, selection of flow rates, selection of surface water quality parameters and pollution parameters of wastewater sources in order to assess the assimilative capacity of each section of the river must ensure the system of each river and river sections. The assessment of the assimilative capacity of rivers and lakes must be conducted for each pollution parameter. The assessment of the assimilative capacity of rivers and lakes must be based on the characteristics of use purposes, self- cleaning capacity of water bodies, the scale and characteristics of current wastewater sources and socio-economic development planning.
Water bodies that must be assessed of assimilative capacity include: Rivers on the list of inter-provincial and inner-provincial river basins; inter-state, inter-provincial and inner-provincial water bodies; and lakes on the list of inter-provincial and inner-provincial water bodies that were promulgated by competent state agencies. For water sources not in the aforesaid cases, the competent agencies shall approve the assimilative capacity, consider and decide the assessment of the assimilative capacity on the basis of the importance of water sources for socio-economic development, the requirements for the protection of water resources and the environment, the preservation of biodiversity, and cultural values related to water sources.
The segmentation of rivers to assess the assimilative capacity of rivers is conducted on the following bases: Location of integrating and separating streams in rivers; function of water sources, purpose of water use; location of works for exploitation and use of water resources, discharge of wastewater; location of reservoirs, water regulation works in the rivers; the maximum length of salinity intrusion for the salinity of 4.0 ‰ for tidal affected river sections; the requirements on conservation and development of aquatic ecosystems, historical values, culture, tourism and beliefs related to water sources. For inter-state and inter-provincial rivers, apart from the above-mentioned regulations, the national border and administrative boundaries of province must also be taken into account.
Methods of assessing the assimilative capacity of rivers include:
Direct assessment method: Assessment of the assimilative capacity of rivers is conducted on the basis of maximum threshold of each assessment parameter based on technical regulations in surface water quality, flow rate and result of water quality analysis of river sections. Direct assessment method is applied to those river sections that do not receive any directly-discharged effluents, which shall be confirmed through surveys.
Indirect assessment method: Assessment of the assimilative capacity of rivers is conducted on the basis of maximum threshold of each assessment parameter based on technical regulations for surface water quality; flow rate and result of water quality analysis of river sections; flow rate and result of analysis of wastewater sources into the river sections.
Modeling assessment method: Assessment of the assimilative capacity of rivers is conducted on the basis of maximum threshold of each assessment parameter based on technical regulations for surface water quality; flow rate and result of water quality analysis of river sections; flow rate and result of analysis of wastewater sources into the river sections; and the process of merging and changing of the pollutants.
The evaluation parameters of the assimilative capacity of rivers and lakes are COD, BOD5, ammonium, nitrate, phosphate, etc. Besides, competent agencies approving the assimilative capacity also must base themselves on technical regulations for surface water quality and wastewater, purpose of water use, scale and characteristics of wastewater, requirements on protection of water sources, environmental protection for each section of rivers and lakes to consider and decide other parameters to have suitable assessment.
MONRE is responsible for approving the assimilative capacity of rivers and lakes that are inter-provincial and inter-state water bodies. Accordingly, the Department of Water Resources Management presides and coordinates with Vietnam Environment Administration to assist MONRE in organizing the investment and assessment of the assimilative capacity of rivers and lakes that are inter- provincial or inter-state water bodies, and consulting with ministries including Ministry of Industry and Trade, Ministry of Agriculture and Rural Development, Ministry of Transport, Ministry of Construction, Ministry of Culture, Sports and Tourism, provincial People's Committees, agencies and units related to the assessment result of the assimilative capacity of rivers and lakes; synthesizes and completes the dossiers and submits them to MONRE for consideration for approval.
The People's Committee of provinces and centrally-run cities is responsible for approving the assimilative capacity of rivers and lakes that are inner-provincial water bodies. Accordingly, the Department of Natural Resources and Environment of provinces and centrally-run cities assist provincial People's Committees in organizing the investment and assessment of the assimilative capacity of rivers and lakes that are inner-provincial water bodies, consulting with departments including Department of Industry and Trade, Department of Agriculture and Rural Development, Department of Transport, Department of Construction, Department of Culture, Sports and Tourism, People's Committees of districts, towns and provincial cities, agencies and units related to assessment result of the assimilative capacity of rivers and lakes; collects all opinions and then sends them to the MONRE for comments; finalizes the dossiers and submits them to the provincial People's Committees for consideration and decision on approval.
Water pollution control is an important part of state management of environmental protection, which has been proved by international experience and management practices in Việt Nam. The issuance of Circular No. 76/2017/TT-BTNMT is an urgent requirement and meets the requirements of the state management of water resources in the current period. However, in the forthcoming time, it is necessary to strengthen measures of monitoring and implementation to prevent and minimize the non-observance of regulations on discharge of polluted water into rivers and lakes that causes environmental pollution.
Assessment of the load capacity, ability to receive wastewater of rivers and lakes must ensure the principles of river basin and river source system
Hàn Ngọc Tài
Department of Waste Management and Environmental Promotion
Vietnam Environment Administration
(Source: Vietnam Environment Administration Magazine, English Edition I-2018)
