Circular No. 64/2017/TT-BTNMT on determining the minimum flow rate in rivers, streams, and downstream of reservoirs and dams

CIRCULAR

PROVISIONS ON DETERMINING THE MINIMUM FLOW ON RIVERS, STREAMS AND LOWER REACHES OF RESERVOIRS AND DAMS

Pursuant to the Law on Water Resources No. 17/2012/QH13 dated June 21, 2012;

Based on Decree No. 201/2013/NĐ-CP dated November 27, 2013 of the Government detailing the implementation of certain provisions of the Water Resources Law;

Pursuant to Decree No. 36/2017/NĐ-CP dated April 4, 2017 of the Government stipulating the functions, tasks, powers, and organizational structure of the Ministry of Natural Resources and Environment;48/2020/NĐ-CP

At the proposal of the Director of the Water Resources Management Agency and the Head of the Legal Department;The Minister of Natural Resources and Environment issues this Circular on determining the minimum flow on rivers, streams and lower reaches of reservoirs and dams.

This Circular stipulates the determination and announcement of the minimum flow on rivers, streams, canals, creeks (hereinafter collectively referred to as rivers, streams) and lower reaches of reservoirs and dams (hereinafter collectively referred to as reservoirs).This Circular applies to state management agencies, organizations, and individuals related to the determination, announcement, and maintenance of the minimum flow on rivers, streams, and lower reaches of reservoirs.Article 3. Principles for Determining the Minimum Flow

PART I

GENERAL PROVISIONS

Article 1. Scope of Regulation

1. The determination of the minimum flow on rivers, streams, and lower reaches of reservoirs must be carried out at specific locations on rivers and streams and must ensure system integrity within river basins.

Article 2. Applicability

2. Ensuring fairness, reasonableness, harmony of interests, and equality of rights among water users, between upstream and downstream localities.

3. Being consistent with the characteristics of water resources, flow regimes on rivers and streams, topography, water demand, the role of rivers and streams in the river system, and other functions of water resources; being consistent with the scale, method of exploitation, and operational capacity of reservoirs.

4. Consistent with agreements and commitments to share benefits in the exploitation and use of water with neighboring countries sharing common water resources.

Article 4. Objectives, Requirements, and Basis for Determining the Minimum Flow

1. After the minimum flow on rivers, streams, and lower reaches of reservoirs has been determined and announced, it shall serve as one of the bases for consideration during the process of drafting, reviewing, and approving the following tasks:

a) Water resource planning; regional planning, provincial planning, and sectoral planning involving the exploitation and use of water resources on rivers and streams;

b) Reservoir operation procedures, inter-reservoir operation procedures on river basins;

c) Plans and schemes for regulating and distributing water resources on river basins;

d) Projects for constructing reservoirs on rivers and streams; projects for transferring water across river basins;

đ) Issuing permits for the exploitation and use of water resources;

e) Projects directly related to maintaining the minimum flow on rivers and streams.

2. The minimum flow on rivers, streams, and lower reaches of reservoirs, once determined, must fall within the range from the smallest monthly flow to the average flow of the three smallest months (m

In cases where there are different requirements, the value of the minimum flow at each location must be determined based on the provisions of Clause 3 of this Article, but the maximum increase shall not exceed the average dry season flow and must be consistent with the actual capacity of water resources and the operational capacity of the reservoir; the maximum decrease shall not exceed 50% of the smallest monthly flow, but must ensure safe water supply and social welfare.

3. Based on the requirements for the minimum flow on rivers, streams, and lower reaches of reservoirs as stipulated in Clause 2 of this Article, during the process of determining the minimum flow, the following factors must be comprehensively and fully considered to select the specific value of the minimum flow at each location appropriately:

a) Hydrological characteristics, flow regime, distribution of flows on rivers and streams, the proportion of contributions of rivers and streams to the river system, and the functions of water resources;³/s).

b) Current status and water demand of direct water users on rivers and streams;

c) Requirements for protecting water resources, preventing degradation and depletion, meeting minimum water needs during severe droughts and water shortages, protecting aquatic ecosystems, biodiversity, ensuring national defense and security, and other requirements related to water resource protection;

d) Scale, scope of impact, method of exploitation, layout of facilities, and water regulation capacity of reservoirs;

đ) Provisions of international treaties to which the Socialist Republic of Vietnam is a member in cases related to transboundary water resources.

4. Depending on the requirements for water exploitation and use regimes and the operational capacity of reservoirs, the specific value of the minimum flow at each location may be considered and determined accordingly for different periods and times of the year.

DETERMINATION AND ANNOUNCEMENT OF THE MINIMUM FLOW

đ) Provisions of international treaties to which the Socialist Republic of Vietnam is a party where relevant to transboundary water resources.

4. Depending on the requirements for water exploitation and utilization regimes and the operational capacity of the reservoirs, the regulating works' capacity, the specific value of the minimum flow at each location may be considered and determined correspondingly for each period and time of the year.

Chapter II

DETERMINATION AND ANNOUNCEMENT OF MINIMUM FLOW

Article 5. Rivers, streams, and reservoirs must determine the minimum flow

1. For rivers and streams, including:

a) Rivers and streams listed in the inter-provincial river basin catalogues and provincial river basin catalogues that have been approved by competent state authorities.

In cases where rivers and streams listed in the inter-provincial river basin catalogues and provincial river basin catalogues do not yet have reservoirs or have not been planned for constructing reservoirs with water extraction and utilization scales requiring water resource exploitation and utilization permits, the competent state authority specified in Article 9 of this Circular shall consider and decide on determining the minimum flow on the river or stream when planning, investing in construction, and issuing permits for water extraction and utilization;

b) Rivers and streams not listed in the inter-provincial river basin catalogues and provincial river basin catalogues but which have reservoirs or have been planned for constructing reservoirs with water extraction and utilization scales requiring water resource exploitation and utilization permits.

2. For reservoirs, including:

a) Reservoirs of hydropower and irrigation works with water extraction and utilization scales requiring water resource exploitation and utilization permits under the laws on natural resources, except in cases where they have already been put into operation and cannot adjust or supplement discharge structures to maintain the minimum flow, and such decisions are made by the competent authority issuing water resource exploitation and utilization permits;

b) Investment projects for constructing reservoirs as stipulated in Point a of this Clause must include discharge structures to maintain the minimum flow, ensuring sufficient capacity to meet the requirements set out in Clause 2 of Article 4 of this Circular.

Article 6. Location for Determining Minimum Flow

The minimum flow is determined for specific locations on rivers and streams or downstream of reservoirs and is implemented as follows:

1. For rivers and streams:

a) The location for determining the minimum flow on rivers and streams is at the mouth of the river or stream before it joins another water body. If there is a hydrological station on the river or stream whose location represents the flow regime of the river or stream, then the hydrological station is selected as the location for determining the minimum flow on the river or stream;

b) In addition to the location specified in Point a of this Clause, if there are specific requirements to ensure water extraction and utilization activities, cultural, sports, and tourism activities, or requirements for protecting aquatic ecosystems, conserving biodiversity, and economically valuable aquatic species on one or more sections of the river or stream, the competent state authority specified in Article 9 of this Circular shall consider and decide on selecting additional locations for determining the minimum flow.

2. For reservoirs:

a) The location for determining the minimum flow downstream of the reservoir is immediately after the dam. If there is a hydrological station downstream of the dam that monitors the flow regime of the reservoir, then the hydrological station is selected as the location for determining the minimum flow. The minimum flow at this location includes the continuously maintained minimum flow and the minimum flow appropriate to the usage regime and time requirements downstream;

b) For reservoirs that interrupt the flow of rivers and streams, in addition to the location for determining the minimum flow specified in Point a of this Clause, the minimum flow must also be determined immediately after the structure that returns the flow to the river or stream or immediately after the hydropower plant. The minimum flow at this location is maintained according to the usage regime and time requirements downstream.

Article 7. Methods for calculating flow characteristics

1. Flow characteristics are calculated at each specific location where minimum flow is determined, including:

a) Annual flow distribution;

b) Annual flow characteristics;

c) Low-flow season characteristics (minimum monthly flow, average minimum monthly flow, and average minimum three-monthly flow).

2. Based on existing meteorological and hydrological observation data and the characteristics of the watershed, the determination of flow characteristics is carried out using one of the following methods in the order of priority:

a) In cases where the series of hydrological observation data has been recorded for twenty years or more and the difference in watershed area between the hydrological station and the location of the minimum flow does not exceed ten percent, direct use of hydrological station data shall be made to determine it;

b) In cases where the series of hydrological observation data has been recorded for twenty years or more but the difference in watershed area between the hydrological station and the location of the minimum flow exceeds ten percent, correlation with hydrological station flow data shall be used to determine it;

c) In cases where the series of hydrological observation data is less than twenty years, consideration and selection of one of the following methods shall be made: applying the watershed analogy method with a hydrological station that has been recording for twenty years or more if the difference in area between the two watersheds does not exceed five times and the two watersheds are similar in basic conditions for forming flow, synchronous flow fluctuation, or applying the correlation method between annual rainfall and annual flow or other hydrological modeling methods.

3. In addition to applying the methods prescribed in Clause 2 of this Article, hydrological modeling methods should also be considered for verification purposes.

4. In cases where multiple locations on the same river or stream have their flow characteristics determined by different methods, the values of these characteristics should be reviewed and adjusted according to the priority order specified in Clause 2 of this Article.

Article 8. Requirements for information, data, and results of determining minimum flow

1. Information and data used to assess and determine minimum flow must ensure compatibility with the applied method and reliability.

In cases where hydrological observation data has been affected by regulation from works on the river or stream, such data must be restored before being used for calculation and assessment.

2. The results of calculating flow characteristics, selecting specific values of minimum flow at each location, must be clearly justified and explained to meet the requirements stipulated in Article 4 of this Circular and the following requirements:

a) Regarding the selection of location;

b) Regarding the selection of the applied method;

c) Meeting the requirements for water exploitation and utilization in terms of flow rate, water level, and temporal flow regime, as well as reservoir regulation.

3. The results of determining minimum flow on rivers and streams must be compiled and presented in a schematic diagram and a list of minimum flows on rivers and streams, including the locations where minimum flow has been determined, each location comprising the following main contents:

a) Name of the river or stream within the watershed;

b) Location of determining minimum flow: coordinates, geographical and administrative location;

c) Values of minimum flow.

4. For reservoirs, the results of calculating and determining minimum flow downstream of the reservoir must be compiled and included in the project proposal, report on surface water exploitation and utilization in the application for permission to exploit and utilize surface water as prescribed by laws on water resources and the project investment construction dossier for the reservoir.

Article 9. Announcement of Minimum Flow

1. For rivers and streams:

The water resources management agency shall assist the Ministry of Natural Resources and Environment in organizing investigations, evaluations, and soliciting opinions from the following ministries: Industry and Trade, Agriculture and Rural Development, Transport, Construction, Culture, Sports and Tourism, People's Committees of provinces and centrally governed cities (hereinafter referred to as provincial People's Committee), and relevant agencies and units regarding the minimum flow on inter-provincial rivers and streams; compile opinions, complete the dossier, and submit it to the Ministry of Natural Resources and Environment for consideration and approval to announce the minimum flow.

b) The Department of Natural Resources and Environment shall assist the provincial People's Committee in organizing investigations, evaluations, and soliciting opinions from the Departments of Industry and Trade, Agriculture and Rural Development, Transport, Construction, Culture, Sports and Tourism, and other relevant departments and agencies regarding the minimum flow on intra-provincial rivers and streams and those specified in Point b Clause 1 Article 5; compile opinions from these departments and agencies, send them to the Ministry of Natural Resources and Environment for comments, complete the dossier, and submit it to the provincial People's Committee for consideration and approval to announce the minimum flow.

c) The dossier for soliciting opinions as stipulated in Points a and b of this Clause includes: the draft Decision approving the minimum flow along with the list of minimum flows on rivers and streams, and the explanatory report on determining the minimum flow, and the schematic diagram of the minimum flow system of rivers and streams.

d) Within ten (10) working days from the date of approval of the minimum flow on rivers and streams, the Ministry of Natural Resources and Environment and the provincial People's Committee, within their respective authority, shall announce the decision approving the minimum flow along with the list of minimum flows on rivers and streams, and post it on the Ministry of Natural Resources and Environment's and the provincial People's Committee's electronic information portal.

2. For reservoirs:

a) The reservoir owner shall be responsible for organizing investigations, evaluations, and presenting the results of calculations and proposals for the minimum downstream flow of the reservoir they have invested in building, managing, and operating in the project proposal, surface water utilization report as prescribed by laws on water resources, and the investment project dossier for constructing the reservoir.

b) Within ten (10) working days from the date of approval of the minimum downstream flow of the reservoir, the Ministry of Natural Resources and Environment and the provincial People's Committee, within their respective authority, shall announce the value of the minimum downstream flow of the reservoir and post it on the Ministry of Natural Resources and Environment's and the provincial People's Committee's electronic information portal.

Article 10. Review, Adjustment, and Supplement of Minimum Flow on Rivers and Streams

1. The review, adjustment of the minimum flow on rivers and streams shall be conducted every five (05) years or in the following cases:

a) There is a revision to the planning related to water extraction and use;

b) A new project or facility for water extraction and use has been established, significantly altering the flow regime of the river or stream;

c) There is significant natural change affecting water sources.

2. The competent authority approving the minimum flow on rivers and streams shall decide on the review, adjustment, and supplementation. The determination and announcement of the minimum flow on rivers and streams shall be carried out in accordance with this Circular.

Chapter III

IMPLEMENTATION AND EFFECTIVE PROVISIONS

Article 11. Reporting System and Transitional Provisions

1. Annually, before December 15th, the Provincial Department of Natural Resources and Environment shall report to the Ministry of Natural Resources and Environment (through the Water Resources Management Agency) and the provincial People's Committee on the determination, approval, and announcement of the minimum flow rate on rivers, streams within the province, and at the downstream of reservoirs within the provincial territory.

2. The minimum flow value already prescribed by competent state agencies in water resources exploitation and utilization permits or in the inter-reservoir operation procedures issued prior to the effective date of this Circular shall continue to be implemented until the permit expires or until there is a decision to adjust or supplement the inter-reservoir operation procedures.

Article 12. Effective date and implementation

1. This Circular takes effect from February 5, 2018.

2. The Water Resources Management Agency shall be responsible for inspecting and guiding the implementation of this Circular.

3. Ministries, ministerial-level agencies, provincial People's Committees, provincial Departments of Natural Resources and Environment under central cities, and related organizations and individuals shall be responsible for implementing this Circular.

During the implementation of this Circular, if there are difficulties or obstacles, organizations and individuals are requested to reflect them to the Ministry of Natural Resources and Environment for research, amendment, and supplementation to ensure appropriateness./.