NB/T 10083-2018Code for water conservancy computation of hydropower projects (English PDF)

Foreword

This document was issued on 29 October 2018 by the National Energy Administration of the PRC and takes effect on 1 March 2019.

It is a NB/T standard: recommended rather than compulsory, but it is the text a Chinese reviewer applies when assessing a submission.

It is classified under ICS 27.140, Chinese classification P 59.

It replaces DL/T 5105-1999, which is superseded.

This code has been revised in accordance with the requirements of the Notice of the National Energy Administration on the Issue of the Second Batch of the 2014 Plan for the Development and Revision of Energy Sector Standards (Guo Neng Ke Ji [2015] No. 12). The drafting group carried out extensive investigation and research, earnestly summarized practical experience, and revised this code on the basis of a wide solicitation of opinions.

The main technical content of this code is: basic data; flood routing calculation; runoff regulation calculation; runoff regulation calculation for jointly operated hydropower projects; preparation of reservoir operation graphs; initial filling calculation for reservoir; sediment scour and deposition calculation for reservoir; backwater calculation for reservoir; water conservancy computation for projects with multiple purposes; and water conservancy computation for other particular problems.

The main technical changes introduced by this revision are set out in the six items that follow.

The provisions concerning initial filling calculation for reservoir, sediment scour and deposition calculation for reservoir, and backwater calculation for reservoir have been revised, and each of them has been made an independent chapter.

The main content of the water conservancy computation for pumped storage power stations and for tidal power stations has been revised.

The former subject runoff regulation of cascade hydropower stations and cross-basin compensation regulation calculation has been revised into runoff regulation calculation for jointly operated hydropower projects.

The former subject water conservancy computation for projects with other water use tasks has been revised into water conservancy computation for projects with multiple purposes.

A clause on scour and deposition calculation in the downstream river channel has been added.

The content relating to water conservancy computation for timber floating tasks has been deleted.

This code is under the administration of the National Energy Administration. The China Renewable Energy Engineering Institute has proposed this code and is responsible for its routine administration, while the Standardization Technical Committee for Hydropower Planning and Reservoir Environmental Protection of the Energy Sector is responsible for the interpretation of its specific technical content.

Comments and suggestions arising during implementation should be sent to the China Renewable Energy Engineering Institute, at No. 2 Liupukang Beixiaojie, Xicheng District, Beijing, postcode 100120.

Chief development organization: PowerChina Northwest Engineering Corporation Limited.

Participating development organizations: PowerChina Huadong Engineering Corporation Limited and PowerChina Zhongnan Engineering Corporation Limited.

Chief drafters: Li Ping, Feng Li, Wang Sheliang, Wang Fei, Zhou Tiezhu, Song Zhen, Zhang Ping, Ren Zaimin, Zhao Song, Yang Zhongmin, Li Jianhua, Rui Defan, Sun Li, Ji Jinhua, Wang Xinjin, Hu Xiaoli, Yang Ting and Ju Bin.

Chief examiners: Wan Wengong, Ma Dengqing, Wang Zhaoyang, Fan Guofu, Zhao Zenghai, Yang Baiyin, Yang Dequan, Chen Senlin, Zhong Ping'an, Guo Yunfeng, Zhang Jianhua, Chen Zhenhong, Zhang Danqing, Zeng Zhaofang, Yang Lifeng, Chen Shouhai, Xu Min, Zhou Lin, Zhao Yi and Li Shisheng.

Publication and approval data

This code is an energy sector standard of the People's Republic of China, numbered NB/T 10083-2018 and titled Code for Water Conservancy Computation of Hydropower Projects. Its Chinese title is printed on the cover as Shuidian Gongcheng Shuili Jisuan Guifan, and the code replaces DL/T 5105-1999.

The cover carries the international classification ICS 27.140, the Chinese standard classification code P 59, and the record number J15-2018. The mark NB in the upper right corner identifies the standard as belonging to the energy sector series administered by the National Energy Administration.

The standard was issued on 29 October 2018 and came into force on 1 March 2019, as printed on the cover in the form 2018-10-29 issued and 2019-03-01 implemented. The issuing body named on the cover is the National Energy Administration.

The title page states that the chief editing department is the China Renewable Energy Engineering Institute (Hydropower and Water Resources Planning and Design General Institute), that the approving department is the National Energy Administration, and that the effective date is 1 March 2019.

The standard was published by China Water and Power Press in Beijing in 2019.

The approval act is reproduced in the front matter as Announcement of the National Energy Administration, 2018 No. 12. Pursuant to the Notice on Issuing the Measures for the Administration of Standardization in the Energy Sector (Trial) and its implementing rules (Guo Neng Ke Ji [2009] No. 52), and following examination, the National Energy Administration approved 204 sector standards, comprising 54 energy standards (NB), 8 petrochemical standards (NB/SH) and 142 petroleum standards (SY), and issued them with that announcement dated 29 October 2018.

In the annexed catalogue of sector standards this document appears under serial number 38, with standard number NB/T 10083-2018, title Code for Water Conservancy Computation of Hydropower Projects, superseded standard DL/T 5105-1999, approval date 29 October 2018 and implementation date 1 March 2019.

Structure of the document

The body of NB/T 10083-2018 is organized in twelve chapters, followed by the explanation of wording, the list of quoted standards and the explanation of provisions. The page numbers below are those printed in the official English Contents of the standard.

Chapter 1, General Provisions, begins on page 1, and Chapter 2, Terms, on page 2.

Chapter 3, Basic Data, begins on page 3 and is divided into 3.1 General Requirements (page 3), 3.2 Hydrological Data (page 3), 3.3 Topographical and Geological Data (page 4), 3.4 Socioeconomic and Project Data (page 4) and 3.5 Multipurpose Data (page 5).

Chapter 4, Flood Routing Calculation, begins on page 6 and is divided into 4.1 General Requirements (page 6), 4.2 Principle and Content (page 6), 4.3 Flood Routing Calculation for Reservoir (page 7) and 4.4 Flood Routing Calculation for Cascade Reservoirs (page 9).

Chapter 5, Runoff Regulation Calculation, begins on page 10, and Chapter 6, Runoff Regulation Calculation for Jointly Operated Hydropower Projects, on page 13.

Chapter 7, Preparation of Reservoir Operation Graphs, begins on page 15, and Chapter 8, Initial Filling Calculation for Reservoir, on page 17.

Chapter 9, Sediment Scour and Deposition Calculation for Reservoir, begins on page 19, and Chapter 10, Backwater Calculation for Reservoir, on page 21.

Chapter 11, Calculation for Hydropower Project with Multiple Purposes, begins on page 23 and is divided into 11.1 Tasks and Principle (page 23), 11.2 Calculation for Project with Irrigation Purpose (page 23), 11.3 Calculation for Project with Water Supply Purpose (page 24) and 11.4 Calculation for Project with Navigation Purpose (page 24).

Chapter 12, Other Particular Calculations, begins on page 25 and is divided into 12.1 Downstream Unsteady Flow due to Hydropower Plant Daily Regulation (page 25), 12.2 Scour and Deposition in Downstream River Channel (page 26), 12.3 Dam-Break Flood (page 26) and 12.4 Ice Flood Control (page 28).

The back matter comprises the Explanation of Wording in This Code on page 29, the List of Quoted Standards on page 30 and the Addition: Explanation of Provisions beginning on page 31.

The front matter of the printed standard is numbered in Roman figures and contains the announcement of approval, the catalogue entry, the foreword, the Chinese contents and the official English Contents, which is reproduced word for word in the table of contents of this record.

1 Scope

NB/T 10083-2018 is the Chinese code for the water conservancy computations of a hydropower project, replacing DL/T 5105-1999. These are the calculations that turn a hydrological record into the numbers a scheme is designed around: how large the reservoir must be, how much energy it will produce in a dry year, how high the flood will rise behind the dam and how far upstream the backwater will reach. The code sets the general provisions, the defined terms and symbols, and the data and design standards on which the computations rest. It then covers flood regulation - the routing of the design and check floods through the reservoir and the determination of the flood control levels - and runoff regulation, with the firm and average output, the energy computation, and the reservoir operation charts that govern day to day running. Sedimentation and its effect on useful storage, the backwater profile upstream, and the water level and discharge relationships downstream follow. The code also addresses multi-purpose operation where irrigation, water supply, navigation and environmental flow share the reservoir with power, the cascade operation of several plants on one river, the dam break wave computation, and the ice regime where winter conditions demand it. Presentation of results and the report close the document. It applies at every design stage of Chinese hydropower projects.

1.0.1 This code is formulated in order to unify the principles, the working content, the depth and the technical requirements to be followed in the water conservancy computation of hydropower projects.

1.0.2 This code applies to the water conservancy computation of hydropower projects.

1.0.3 Water conservancy computation shall be carried out on the basis of the development tasks and the project conditions, in combination with the requirements of ecological and environmental protection and of the comprehensive utilization of water resources, with overall consideration and rational arrangement, and shall take the maximization of the overall benefit as its objective.

1.0.4 Water conservancy computation shall attach importance to the collection, sorting, evaluation and re-examination of the data.

1.0.5 Water conservancy computation shall attach importance to the analysis of the mutual influence between the project and other relevant projects, and shall coordinate the relations among them in an overall manner.

1.0.6 Water conservancy computation shall select the computation model rationally and determine the parameters, and shall carry out a rationality analysis of the computation results.

1.0.7 In addition to complying with this code, the water conservancy computation of hydropower projects shall also comply with the provisions of the relevant current national standards.

2 Terms

Chapter 2 of the code defines four terms, each given in Chinese with its official English equivalent followed by the definition. The terms are static storage capacity, dynamic storage capacity, overall output factor and flood regulation mode.

2.0.1 Static storage capacity: the storage capacity below the horizontal water surface corresponding to a given water level.

2.0.2 Dynamic storage capacity: the storage capacity below the water surface corresponding to a given moment in time.

2.0.3 Overall output factor: the factor used to calculate the generating output of a hydropower station, obtained by taking comprehensive account of turbine efficiency, generator efficiency, gravitational acceleration, the mode of operation and the other factors that affect generation losses.

2.0.4 Flood regulation mode: the reservoir impounding and discharging rule prescribed in the flood routing calculation.

3 Basic data

3.1.1 Water conservancy computation shall collect data on hydrology, topography, geology, socioeconomic conditions, ecological and environmental protection and the state of the power system, together with the requirements of comprehensive utilization and the present state and planning of the relevant water resources and hydropower projects.

3.1.2 The data collected shall be sorted and subjected to a rationality analysis.

3.2.1 Meteorological data shall include the statistical results for the main meteorological elements such as precipitation, air temperature, evaporation, wind speed and wind direction, together with the results of the analysis of the seasonal variation pattern of rainstorms and of their regional distribution characteristics.

3.2.2 Runoff data shall include annual, monthly, ten-day and daily runoff series, statistical data on annual runoff, and the results of the analysis of the intra-annual distribution and inter-annual variation of runoff, of the annual dry period and of continuous dry periods over several years. Hydropower projects with annual or multi-year regulation performance shall collect annual and monthly runoff data; projects with seasonal regulation shall collect ten-day and daily runoff data; projects with daily regulation, weekly regulation or run-of-river operation shall collect daily runoff data.

3.2.3 The length of the runoff series adopted in the computation shall not be less than thirty years.

3.2.4 For the runoff regulation calculation of a group of hydropower stations, runoff data covering the same period for each of the stations shall be collected.

3.2.5 Flood data shall mainly include the statistical parameters of flood peak and of flood volume for different durations, the measured typical flood hydrographs and the design values of floods of the various frequencies, the design flood hydrographs, the temporal distribution pattern of floods, the regional composition of floods and the flood routing parameters.

3.2.6 For hydropower projects that undertake downstream flood control tasks, flood data for the control sections of the downstream flood control objects and for the intervening areas shall be collected.

3.2.7 For the joint flood routing calculation of a group of reservoirs, data shall be collected on the floods of the relevant projects, on the floods of the intervening areas and on the corresponding regional composition of the floods.

3.2.8 Where floods show a marked seasonal character, data shall be collected on the division of the year into periods and on the corresponding staged design floods.

3.2.9 Stage-discharge relation curves shall include the natural stage-discharge relation curves for the dam site of the hydropower project, the powerhouse tailwater section, the flood control section, the control sections of the reservoir backwater area and the relevant sections of the downstream river channel, as well as the stage-discharge relation curves that take account of the backwater effect of completed or under-construction water projects downstream, of scour and deposition in the river channel and of construction effects.

3.2.10 Sediment data shall mainly include the sources and composition of the sediment, the suspended sediment concentration, the sediment transport rate, the results of the particle size grading analysis, the bed load transport rate, the sediment retaining and sediment regulating effect of the upstream projects, and the observation and analysis data on sedimentation in similar completed reservoirs.

3.2.11 Ice regime data shall mainly include the icebound river reach, the ice thickness, the ice volume, the dates of freeze-up and of break-up, the causes of the formation of ice jams or ice dams and the relevant investigation data.

3.2.12 Tidal data shall mainly include the tidal characteristics such as tidal range, tidal level and the times of rising and falling tides, together with storm surges, long tidal series or representative tides, typical tidal levels, design tidal levels and tidal process lines.

3.3.1 Topographic data shall include the topographic map of the reservoir area, the measured longitudinal and cross sections of the reservoir area and of the relevant downstream river reaches, and the plan location maps. The scale of the topographic map of the reservoir area shall not be smaller than one to ten thousand, and for the reservoir areas of pumped storage stations and tidal power stations the scale should not be smaller than one to five thousand. A unified coordinate system and a unified elevation system shall be adopted.

3.3.2 Geological data shall mainly include the investigation and analysis data on bank collapse in the reservoir area, on landslides, on debris flows, on leakage, on the groundwater level and on inundation.

3.4.1 Socioeconomic data should include the present state and the development planning of the national economy of the relevant areas upstream and downstream of the project, mainly including the gross domestic product, industry, agriculture, forestry, animal husbandry, transport, population, land, mineral resources and cultural relics and historic sites.

3.4.2 The data on the development and utilization planning of the river basin and of the river reach should mainly include the comprehensive basin plan, the basin flood control plan and the hydropower plan, together with the requirements placed on the operation of the river and of the hydropower plants by water environment improvement, ecological protection, water resources allocation and the power system.

3.4.3 Power system data shall mainly include the present state and the development planning of the power system that the designed hydropower station is part of, the composition of the power sources and the load characteristics of the system.

3.4.4 Environmental protection data shall mainly include the discharge flows required by the downstream ecology and by landscape needs, together with the requirements as to the periods of ecological regulation of the reservoir and the permissible intra-day water level fluctuation.

3.4.5 Data shall be collected on the characteristics of the completed, under-construction and planned water resources and hydropower projects existing within the design horizon year.

3.5.1 Hydropower projects that also undertake flood control tasks shall collect the flood control planning data of the area in which they are located, mainly including the present state and the planning of flood control in the corresponding flood control area, the flood control standard of the protected objects, the safe discharge of the control sections, the flood control measures, the requirements placed on the designed hydropower project, and the extent of the area affected and the losses suffered by the protected objects under different flood discharge conditions.

3.5.2 Hydropower projects that also undertake irrigation tasks shall collect the irrigation planning data of the corresponding irrigation districts, mainly including the near-term and long-term scale and distribution of the irrigation districts, the irrigation water demand and its process, the design assurance rate, the extent to which and the manner in which water supply may be reduced in the dry years falling outside the assurance rate, the mode of water withdrawal, and the elevation and position of the intake.

3.5.3 Hydropower projects that also undertake industrial and municipal water supply tasks shall mainly collect the near-term and long-term water supply quantities, their intra-annual distribution, the water supply assurance rate and the data on the position and elevation of the intake.

3.5.4 Hydropower projects that also undertake navigation tasks shall mainly collect the near-term and long-term passenger and freight traffic volumes, the direction of traffic, the waterway grade, the navigable time and its assurance rate, the maximum daily and hourly water level fluctuation, and the other data on the requirements placed on the designed hydropower project by navigation.

3.5.5 Hydropower projects that also undertake ice flood control tasks shall mainly collect data on the position and extent of the ice flood reach, on the timing requirements of ice flood control, on the general socioeconomic situation of both banks, on the investigation of ice disasters and on the requirements placed on the designed hydropower project.

4 Flood routing calculation

4.1.1 The maximum discharge released by the reservoir after the flood routing calculation shall not be greater than the maximum flow of the flood process concerned.

4.1.2 Flood routing calculation shall be carried out for the different combination schemes, and the results of the most unfavourable scheme shall be adopted.

4.2.1 The starting water level for regulation, the flood regulation principle and the computation method shall be established, and the reservoir water level, the discharge process and the characteristic values shall be presented for the floods of each standard.

4.2.2 The flood characteristics of the basin in which the project is located and of the areas related to the flood protection objects shall be analysed and studied, including the regional composition of the floods, their seasonal variation, the rise and fall of water levels, and flood routing in the river channel.

4.2.3 The design flood process of the dam site section shall be adopted. For reservoirs in which the conditions of runoff generation and concentration change markedly after the reservoir is formed, and where the difference between the design flood of the dam site section and the reservoir inflow design flood is large, the reservoir inflow design flood process should be adopted. Where the design flood process of the dam site section is adopted, static storage capacity shall be used in the flood routing calculation; where the reservoir inflow flood process is adopted, dynamic storage capacity or an unsteady flow method shall be used in the flood routing calculation.

4.2.4 A flood regulation mode that is simple, feasible and operable shall be established on the basis of the flood control task, the flood characteristics, the flood control standard, the permissible discharge of the downstream flood control section and the discharge capacity of the project works.

4.2.5 Where flood routing calculation is carried out by controlling the discharge in grades, it shall proceed in order from the smaller floods to the larger floods. The regulation calculation for the floods of each frequency shall adopt a unified flood regulation rule.

4.2.6 For the regulation calculation of the design flood and of the check flood of each structure, the code states that it is not advisable to take flood conditions of a certain kind into account; the sentence continues on the following page of the standard, which lies outside the part reproduced in this preview.