Chapter 3 Management of Water Sources in Powerhouses, Assurance of Meteorology and Hydrology

Section 1 Water Regulation

Article 76. (Article 76) Principle of exploitation of water resources

This article stipulates that the Owner must prepare a plan on water use after due consultationwith water users of other economic sectors such as waterway transportation, irrigation, aquaculture, and water supply for life and industry so that a plan on water use of one water user may not damage other water users’ benefit.

Article 76 was prepared based on the requirements in Decree No.112/2008/ND-CP. Relevant articles of decrees are as follows:

Decree No.112/2008/ND-CP:

Article 8: Exploitation and use of reservoir’s resources and environment

1.The exploitation and use of resources and environment inthe protective corridor of reservoir and in reservoir must be based on scheme and plan approved by authorized office, ensuring not to affect the duty of reservoir; keep to technical stipulations of related industries or fields and keep to stipulations of landscape and environment protection; not affecting the technical characteristics of reservoir, and not blocking much water current into reservoir.

2.Precinct people’s committee, communal people’s where the reservoirs locate are responsible for

reservoir’s owner in writing and by authorized office according to stipulation of law.

4.The following activities in protective corridor of reservoir and in reservoir (except for the stipulations in section 5 of this Article) can only be implemented when they are approved by the owner in writing and certified by authorized office according to stipulation of law:

a)Building new project;

b)Letting out sewage into water source of reservoir;

c)Exploiting, using water resource of reservoir;

d)Drilling, digging for inspection, geological investigation, exploration, implementation of projects for exploiting underground water, drilling and digging investigation for exploiting minerals; drilling and digging investigation for exploiting construction materials;

đ) Planting long term trees;

e) Activities of tourism, sports, scientific research, business, services;

g)Activities of vehicles (except for two-wheel motors, tri-motors, motorbikes and vehicles for disables);

h)Building warehouses, grounds; stations for cargo or passengers; gathering material, fuel, vehicles;

i)Building breeding facilities, grazing cattle, raising aquatic products;

k)Burying, spilling waste, discarded stuffs;

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l)Exploding mines and other activities causing explosion without harm

m)Building underground projects, including oil pipes, electric cables, informatics cable, supplying and drainage water pipes.

5.The following activities are forbidden in reservoir:

a)Building houses, residential living quarter;

b)Building husbandry breeding facilities, building ponds for cultivating aquatic products;

c)Burying, filling up waste, discarded stuffs;

d)Exploding mines and other activities causing harmful explosion.

Article 77. (Article 77) Plan on water use

Article 77 was prepared based on the requirements in Decree No.112/2008/ND-CP. Relevant articles of decrees are as follows:

Decree No.112/2008/ND-CP:

Article 9: Regulating water of reservoir

1.Operating process of reservoir should be established and submitted to authorized office for approval before accumulating water of reservoir, satisfying fully duties of reservoir in priority order, ensuring the safety of project, safety of reservoir’s lowlands, general exploit resources and environment of reservoir, maintain minimal water current in the reservoir’slowlands, not causing much change to current at reservoir’s lowlands and consider the factor of climate changing; go with operating process of join reservoirs in river valley (if exist) approved by authorized governmental office.

2.The owners of reservoir have duties to supervise, collect information, data of hydrometeorology

by their own expense to serve the demand of protection, management, operation, exploitation of reservoir as instruction of governmental managing office for resources and environment and send annual report of implementing result to specialized managing Ministry and related provincial people’s committee.

4.The plan of water regulation in reservoir is established based on operating process of reservoir approved by authorized governmental office, demand of maintaining minimal water current, forecast of current changing in the year from hydro meteorological office and the water using demand by sections, local area, economic organizations.

5.In case, offices, related organizations and locality don’t agree with the plan of water regulation in reservoir, they can send their petition to owner of reservoir and authorized governmental offices to consider, decide the plan of water regulation in reservoir.

Article 78. (Article 78) Water discharge and storage regime

Article 78 was prepared to let the dam Owner regulate the reservoir water level and discharge water according to the reservoir operation rule prepared after due consultation with other water users.

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reservoir must not be higher thanthe water level stipulated by the State competent management organization.

Article 10. Regulation of water in reservoir

1.The regulation of water in the reservoir shall be in compliance with the following:

a)Water level in the reservoir shall not be higher than water level stipulated by the State competent management organization;

The paragraph 4 is based on Chapter III of Decree No.72/2007/ND-CP and aims at giving priority to flood control over a reservoir operation of other purposes in the flood season.

Article 10. Regulation of water in reservoir

2.The regulation of water in the reservoir shall be in compliance with the following:

b)In flood season, the water reservoirs are responsible for flood control, the operation on water filling and flood discharging shall be prioritized for ensuring dam safety, and the flood control and water filling shall be in compliance with the functions of the projects.

Article 79. (Article 79) Adjustment of hydraulic characteristics of spillway and runoff

Article 79 was prepared to let the dam Owner study, from time to time based on the latest data obtained during the operation stage, how to discharge floods from spillway to minimize damage to the downstream area.

The dam Owner must consider the optimum way to discharge floods from spillway based on

Here, the hydraulic characteristics of spillway will not change from the design in principal unless a remedial work or replacement of spillway gates is conducted. In the case that a remedial work or replacement is made on the spillway gates structure, it is essential to modify the operation rule and the modified rules must be reported to the competent authority for approval.

The hydraulic characteristics of natural runoff may change from time to time depending on changes in the conditions of river basin. Therefore, it is essential to measure the daily river flow as well as flood flow in order to know the change in characteristics of river runoff and flood hydrographs. Then, the

Article 80. (Article 80) Operating manuals for spillway

Article 80 was prepared based on the requirements in Circular No.34/2010/TT-BCT. Relevant articles of decrees and circulars are as follows:

Circular No.34/2010/TT-BCT:

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Article 10. Hydropower reservoir operation procedure

1.The procedures are prepared by the dam’s owner in compliance with the provisions of Decision No. 285/2006/QD-TTg of the Prime Minister dated December 25, 2006 regarding the power for promulgation and execution of the hydropower reservoir operation procedure, and submitting to competent authority prior to reservoir impounding;

2.Competence for approving reservoir operation procedure

a.MOIT approves the procedure of reservoir having capacity of equal or greater than 1,000,000 m3 or for reservoirs located in more than two provinces, except for cases

complying with the provisions in Article 12 of Decree 112/2008/ND-CP of the Government

dated October 20,2008 regarding the comprehensive protection, management and exploitation of resources and environment of hydropower and hydraulic reservoir;

b.The provincial People’s Committee approved the procedures for remaining cases.

3.The regulation of water reservoirs shall follow the provisions in the approved procedures.

4.Trial test for gates of the structures

a. Procedure of dry test for gates is prepared by dam’s owner depending on the characteristics of the structures and conduct this test at least once a year before the flood

season. Repair works for the gates after dry test shall be finished before the annual flood season;

b.Procedure of wet test for gates is prepared by dam’s owner. Depending on hydrological conditions and the characteristics of each structure, the gates wet test can be carried out by beginning of flood season but shall not affect to the downstream area when discharging water through the spillway.

Decision No: 285/2006/QD-TTg

Article 1. Scope and objects subjected for appliance

1.This Decision regulates content of the operation procedures of hydropower reservoirs, competence and responsibilities of organizations, individuals toward the preparation, submission and compliance of reservoir operation procedure.

2.This Decision shall be applied by organizations, and individuals of every sectors who involve in construction investment, management and exploitation of hydropower reservoirs, except for cases using small-scale reservoirs for generation of house-hold purpose.

Article 2. Content of the reservoir operation procedures

1.Mission of the hydropower structures.

2.Main criteria of the hydropower structures:

a)Name and location of the structures;

b)Main criteria of the reservoirs and structures;

c)Criteria of relevant equipment (Number of units, capacity, and specifications of operation equipment).

3.Detailed provisions of the reservoir operation procedures:

a)Provisions on flood prevention mission:

-Periods of early flood, main flood and late flood;

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-Water level of reservoirs in periods of early flood, main flood and late flood;

-Performance of reduction of frequent flood and big flood for downstream (implemented for structures with flood reduction mission for downstream);

-Handling procedure of valve gate insuring safety operation which shall ensure water level of reservoirs not exceeding designated level of all cases;

-Coordination principle between flood reduction and control structures (if any).

b)Provisions on power generation mission:

-Working regime of hydropower plants in the system;

-Requirement of water release volume for the downstream ensuring ecological flow (if any);

-Requirement of downstream level fluctuation caused by operation procedure regime of the plants (if any);

-Coordination principle of generation mission amongst other sub-missions (if any).

4.Responsibilities to organize the reservoir operation:

a)Responsibilities of organizations and individuals issuing orders;

b)Responsibilities of organizations and individuals carrying out those orders;

c)Responsibilities to notify the orders to affected area caused by valve operation;

d)Responsibilities relating to the safety of the structures;

e)Principles in dealing with the accidents when operating the structures;

f)Responsibilities of inspecting the structures and reservoirs before and after flood season;

g)Responsibilities in dealing with damage and faults relating to the structures, and equipment which ensure the safety of exploitation and operation of hydropower structures and reservoirs during flood season.

Article 3. Competence to approve the reservoir operation procedure

1.Prime Minister shall approve the operation procedure for specially important reservoirs whose control regimes impact strongly to the safety of dykes and social-economic activities of provinces, cities or neighbouring countries.

Industry Ministry shall appraise and submit the mentioned procedures to Prime Minister for review and approval.

2.Ministry of Industry shall take lead and collaborate with MARD, National Steering Committee of Flood Prevention and relevant local authorities for appraisal and approval of the operation procedure of reservoirs with capacity equal or greater than 1,000,000 cu.m, except for reservoirs stated in Clause 1 of this Article.

3.People’s Committees of Provinces, Cities shall take lead and collaborate with relevant agencies and Local Steering Committee of Flood Prevention for appraisal and approval of operation procedure of the local reservoirs with capacity lower than 1,000,000 cu.m. This approval Decision shall be sent to Ministry of Industry for consolidation and management.

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Article 4. Organization for execution

1.Ministry of Industry shall take lead and collaborate with MARD, National Steering Committee of Flood Prevention and relevant local authorities for inspecting the execution of this Decision and the approved operation procedures of reservoirs; solving problems and proposing Prime Minister for amendment and supplementation of the Decision if necessary.

2.People’s Committees of Provinces and Cities shall disseminate, instruct and inspect the execution of this Decision and the locally-approved operation procedures of reservoirs; solving problems and proposing competent authorities for amendment and supplementation of the Decision if necessary.

3.Responsibilities of organizations and individuals who are investors and owners using, exploiting and operating the hydropower structures:

a)Investors of newly constructed structures shall prepare the operation procedures of hydropower reservoirs and submit to the competent level for approval synchronously with the appraisal of basic design;

b)Owners of the operated structures shall prepare the operation procedures of hydropower reservoirs and submit to the competent level for issuance within 03 months since the effective date of this Decision;

c)Owners who use, exploit and operate the hydropower structures shall take liabilities relating to the compliance of the reservoir operation procedures.

4.The operation procedures issued before the effective date of this Decision shall be revised and supplemented in compliance with the content of this Decision and relevant regulations.

Article 81. (Article 81) Spillway operation

Article 81 is related to the requirements in Decree No.72/2007/ND-CP and Decision No: 285/2006/QD-TTg. Relevant articles of the decree and decision are as follows:

Decree No.72/2007/ND-CP:

Article 22. Prevention against floods, inundation for downstream area of dam

1.In case, water discharge from reservoir makes sudden increase of water level in the river sections in the downstream sides of the flood discharge structure, the dam Owner shall have measures to announce in advance in order to ensure safety for people, ships, boats, and transporting means going through rivers, streams.

2.The dam Owner shall prepare the alternative of prevention and protection against flood, typhoon for dam protection for the downstream areas, submit the alternative to the State competent organization, in order to cope with the inundation situation due to urgent water flood discharge or situation of dam break, in order to protect lives of people and mitigate

damages of lives and properties of the downstream areas of the dam.

Decision No: 285/2006/QD-TTg:

Article 2. Content of the reservoir operation procedures

1.Mission of the hydropower structures.

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2.Main criteria of the hydropower structures:

a)Name and location of the structures;

b)Main criteria of the reservoirs and structures;

c)Criteria of relevant equipment (Number of units, capacity, and specifications of operation equipment).

3.Detailed provisions of the reservoir operation procedures:

a)Provisions on flood prevention mission:

-Periods of early flood, main flood and late flood;

-Water level of reservoirs in periods of early flood, main flood and late flood;

- Performance of reduction of frequent flood and big flood for downstream (implemented for structures with flood reduction mission for downstream);

-Handling procedure of valve gate insuring safety operation which shall ensure water level of reservoirs not exceeding designated level of all cases;

-Coordination principle between flood reduction and control structures (if any).

b)Provisions on power generation mission:

-Working regime of hydropower plants in the system;

-Requirement of water release volume for the downstream ensuring ecological flow (if any);

-Requirement of downstream level fluctuation caused by operation procedure regime of the plants (if any);

-Coordination principle of generation mission amongst other sub-missions (if any).

4.Responsibilities to organize the reservoir operation:

a)Responsibilities of organizations and individuals issuing orders;

b)Responsibilities of organizations and individuals carrying out those orders;

c)Responsibilities to notify the orders to affected area caused by valve operation;

d)Responsibilities relating to the safety of the structures;

e)Principles in dealing with the accidents when operating the structures;

f)Responsibilities of inspecting the structures and reservoirs before and after flood season;

g)Responsibilities in dealing with damage and faults relating to the structures, and equipment which ensure the safety of exploitation and operation of hydropower structures and reservoirs during flood season.

Article 3. Competence to approve the reservoir operation procedure

1.Prime Minister shall approve the operation procedure for specially important reservoirs whose control regimes impact strongly to the safety of dykes and social-economic activities

of provinces, cities or neighbouring countries.

Industry Ministry shall appraise and submit the mentioned procedures to Prime Minister for review and approval.

2.Ministry of Industry shall take lead and collaborate with MARD, National Steering Committee of Flood Prevention and relevant local authorities for appraisal and approval of

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the operation procedure of reservoirs with capacity equal or greater than 1,000,000 cu.m, except for reservoirs stated in Clause 1 of this Article.

3. People’s Committees of Provinces, Cities shall take lead and collaborate with relevant agencies and Local Steering Committee of Flood Prevention for appraisal and approval of operation procedure of the local reservoirs with capacity lower than 1,000,000 cu.m. This approval Decision shall be sent to Ministry of Industry for consolidation and management.

Article 4. Organization for execution

1.Ministry of Industry and Trade shall take lead and collaborate with MARD, National Steering Committee of Flood Prevention and relevant local authorities for inspecting the execution of this Decision and the approved operation procedures of reservoirs; solving problems and proposing Prime Minister for amendment and supplementation of the Decision if necessary.

2.People’s Committees of Provinces and Cities shall disseminate, instruct and inspect the execution of this Decision and the locally-approved operation procedures of reservoirs; solving problems and proposing competent authorities for amendment and supplementation of the Decision if necessary.

3.Responsibilities of organizations and individuals who are investors and owners using, exploiting and operating the hydropower structures:

a)Investors of newly constructed structures shall prepare the operation procedures of hydropower reservoirs and submit to the competent level for approval synchronously with the appraisal of basic design;

b)Owners of the operated structures shall prepare the operation procedures of hydropower reservoirs and submit to the competent level for issuance within 03 months since the effective date of this Decision;

c)Owners who use, exploit and operate the hydropower structures shall take liabilities relating to the compliance of the reservoir operation procedures.

4.The operation procedures issued before the effective date of this Decision shall be revised and supplemented in compliance with the content of this Decision and relevant regulations.

authorities in advance”, the dam Owner does not have to inform the downstream area of dischargeby hydropower generation in principle, however, the dam Owner is recommended to consider installation of an alarm system in case sudden fluctuation of discharge through turbine for hydropower generation cause dangerous situation for human life working in the downstream area.

Article 82. (Article 82) Discharge capacity for design flood and check flood

Article 82 was prepared to secure safety margin for discharge capacity of spillway to prevent dam from being breached or overtopped due to flood inflow which exceeds spillway capacity.

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In calculating design discharge capacity of a spillway, discharge capacity of other outlet works, fish way, ship lock or other works through which reservoir water flows must not be counted as decrees or circulars related to management of dam safety require.

In calculating the actual maximum discharge of a spillway, discharge capacity of other outlet works, fish way, ship lock or other works through which reservoir water flows must be counted to estimate the whole discharge for record.

The dam Owner must prepare emergency rules to mobilize discharge facilitiesincluding a spillway considering occurrence of extreme flood which may exceed design discharge capacity of a spillway and must negotiate about use of those outlet works in case of emergency with related organizations which manage those outlet works at ordinary times.

Article 82-a1. (Article 82-a1) Warning on dam failure

responsible for organizing rescuing works on the dam and participating in rescuing works for the dams of the other localities in compliance with laws.

In addition, the dam Owner must prepare a suitable type of a warning system in a proper manner and location in cooperation with the People Committees.

Article 82-a2. (Article 82-a2) Measurement of downstream water level

Article 82-a2 was prepared to let theOwner measure the tailrace water level for observation of the head for power generation for proper monitoring of power plant operation.

Measurement of the downstream water level or the tailrace water level is indispensable to observe the head for power generation The Owner must put a measuring device of the downstream water level of a dam or the tailrace water level at a suitable place.

Article 82-a3. (Article 82-a3) Protection of downstream areas from inundation

Article 82-a3 is related to the requirements in Decree No.72/2007/ND-CP and the guideline for this article can be referred to that for Article 81.

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