1、BSI Standards PublicationBS ISO 26906:2015Hydrometry Fishpasses atflow measurement structuresBS ISO 26906:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 26906:2015. Itsupersedes BS ISO 26906:2009 which is withdrawn.The UK participation in its preparation
2、was entrusted to TechnicalCommittee CPI/113/2, Flow measurement structures.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapp
3、lication. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 81111 1ICS 17.120.20Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Commi
4、ttee on 30 November 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 26906:2015 ISO 2015Hydrometry Fishpasses at flow measurement structuresHydromtrie chelles poissons auprs des structures mesurant le dbitINTERNATIONAL STANDARDISO26906Second edition2015-10-15Refe
5、rence numberISO 26906:2015(E)BS ISO 26906:2015ISO 26906:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any mean
6、s, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214
7、 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 26906:2015ISO 26906:2015(E)Foreword vIntroduction vi1 Scope . 12 Normative references 13 Terms and definitions . 14 Symbols 25 Principle 46 Installation . 46.1 Requirements for gauging structure a
8、nd fishpass installations . 46.1.1 Selection of site . 46.1.2 Installation conditions 56.1.3 Upstream channel . 66.1.4 Separate channel 66.1.5 Downstream channel . 76.1.6 Flow measurement and fishpass structures 76.1.7 Maintenance 76.1.8 Measurement of head 86.2 Requirements specific to the fishpass
9、. 86.2.1 General 86.2.2 Guidelines for basic parameters of fishpasses . 96.2.3 Location and attraction flows . 96.2.4 Downstream entry/exit to fishpass . 96.2.5 Upstream exit/entry from fishpass 107 Fishpass performance 107.1 General 107.1.1 Types . 107.1.2 Fishpasses with interconnected pools .107.
10、1.3 Fishpasses with continuous energy dissipation 107.1.4 Calibration and discharge coefficient .117.2 Larinier super-active baffle fishpass with baffle sizes between 75 mm and 150 mm .117.2.1 Description .117.2.2 The following features apply to the range of baffle sizes from 75 mm to 150 mm .127.2.
11、3 Limitations . 137.2.4 Modular flow calibration . 147.2.5 Modular limit .157.3 Pool-type fishpass with V-shaped overfalls. 157.3.1 Description .157.3.2 Determination of discharge under free flow conditions 187.3.3 Modular limit .217.3.4 Determination of discharge under submerged flow conditions 227
12、.3.5 Limitations . 237.3.6 Scaling up to standard design 237.4 Dutch pool and orifice fishpass 237.4.1 Description .237.4.2 Determination of discharge . 257.4.3 Scaling up the standard design . 278 Computation of discharge 278.1 Principles 278.2 Details 289 Uncertainties in flow determination 28 ISO
13、 2015 All rights reserved iiiContents PageBS ISO 26906:2015ISO 26906:2015(E)9.1 General 289.2 Combining uncertainties . 299.3 Uncertainty in the discharge coefficient u*(CDe)68for the fish-pass .309.4 Uncertainty in the effective head . 309.5 Uncertainty budget. 309.5.1 General. 309.5.2 Compound str
14、uctures sources of uncertainty .3110 Example .3110.1 Installation . 3110.2 Flow conditions . 3210.3 Computation of discharge 3210.3.1 Modularity 3210.3.2 Flow over the flat-V weir 3210.3.3 Flow through the fish-pass. 3310.3.4 Total flow . 3310.3.5 Uncertainty in flow through the fish-pass 3310.3.6 U
15、ncertainty in flow over the flat-V weir .3410.3.7 Uncertainty in total flow 3410.3.8 Reduction in overall uncertainty if second head gauge were to be installed upstream of the fish-pass 34Annex A (informative) Introduction to measurement uncertainty .35Annex B (informative) Performance guide for hyd
16、rometric equipment for use in technical standards.44Bibliography .48iv ISO 2015 All rights reservedBS ISO 26906:2015ISO 26906:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing Inte
17、rnational Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison wi
18、th ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives
19、, Part 1. In particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).Attention is drawn to the possibility that some of
20、the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations
21、 received (see www.iso.org/patents).Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISO
22、s adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 113, Hydrometry, Subcommittee SC 2, Flow measurement structures.This second edition cancels and replaces the fir
23、st edition (ISO 26906:2009), which has been technically revised. ISO 2015 All rights reserved vBS ISO 26906:2015ISO 26906:2015(E)IntroductionFlow gauging structures are commonly used for the determination of open channel flows. To operate satisfactorily, these structures require a head difference to
24、 be generated between the upstream and downstream water levels. At structures designed to operate in the modular flow range, an upstream head measurement is used to interpret flow rates. At structures designed to operate in both the modular and drowned flow ranges, the upstream head measurement is a
25、ugmented by a second measurement which senses tailwater conditions. The former type tends to require higher head losses over the structure.In recent years, greater emphasis has been placed on environmental issues, including the free migration of fish in watercourses. It is acknowledged that flow mea
26、surement structures, with their requirement for a head loss between upstream and downstream conditions, that create high velocities may inhibit the movement of fish. It has become important, therefore, to consider ways of aiding fish migration without significantly affecting flow measurement accurac
27、y.vi ISO 2015 All rights reservedBS ISO 26906:2015Hydrometry Fishpasses at flow measurement structures1 ScopeThis International Standard specifies requirements for the integration of fishpasses with flow measurement structures. It identifies those fishpasses which have satisfactory hydrometric calib
28、ration data and gives methods for computing combined flows and uncertainties.NOTE Flow measurement structures and fishpasses have inherently different hydraulic performance criteria. Flow measurement structures perform better with uniform flow patterns; conversely, fish passage performance is improv
29、ed by the variability of the flow conditions that allow fish and other aquatic inhabitants to select the passage conditions that best meet their mode of movement. This International Standard does not suggest that the fishpasses discussed are the preferred methods of fish passage or that they are goo
30、d enough that passage performance can be sacrificed to obtain a single structure that meets both the fish passage and flow measurement requirements.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its applicatio
31、n. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 772, Hydrometry Vocabulary and symbolsISO 14139, Hydrometric determinations Flow measurements in open channels using structures Compou
32、nd gauging structures3 Terms and definitionsFor the purpose of this document, the terms and definitions given in ISO 772 and the following apply.3.1fish pass design rangerange of flows within which fish require passageNote 1 to entry: This may be defined on an annual or a seasonal basis, e.g. for sp
33、awning.Note 2 to entry: In some countries the design range is determined in terms of flow statistics. For example, the design range for coarse fish in the UK is usually between the estimated mean daily flow that is exceeded 95 % of the time and the mean daily flow that is exceeded 20 % of the time.
34、While for migratory salmonids including sea trout and salmon, it is 95 % and 90 % to 10 % respectively.INTERNATIONAL STANDARD ISO 26906:2015(E) ISO 2015 All rights reserved 1BS ISO 26906:2015ISO 26906:2015(E)4 SymbolsWhere a symbol applies to a particular type of fishpass, it is indicated as follows
35、.L indicates applicable to the Larinier super-active baffle fishpass (see 7.2)PT indicates applicable to the pool type fishpass with V-shaped overfalls (see 7.3)PO indicates applicable to the Dutch pool and orifice fishpass (see 7.4)D indicates distance between baffles in a Larinier Fish PassS indic
36、ates the Slope of the Larinier Fish Pass in degreesSymbol Term Unita height of baffle L mafpproportion of total flow through fish-pass Lb orifice width PO mb crest breadth measured at transverse section of upstream baffle L mbfmsproportion of total flow through flow measuring structure LB total widt
37、h of fishpass channel L mB pool width PT and PO mB2width of the non-aerated nappe PT mC characteristic discharge coefficient POCdedimensionless coefficient of discharge LCDcharacteristic discharge coefficient PTCVcoefficient for the approach velocity PTD longitudinal spacing of transverse baffles L
38、mD pipe diameter PO mg acceleration due to gravity All m/s2hmaxmaximum head mhvorifice height PO mh1upstream gauged head relative to transverse section of upstream baffle L mh1upstream head PT mh2downstream head PT mH1upstream total head relative to transverse section of upstream baffle L mH1upstrea
39、m total head PT mH1eeffective upstream total head relative to transverse section of upstream baffle Lm2 ISO 2015 All rights reservedBS ISO 26906:2015ISO 26906:2015(E)Symbol Term Unitkhhead correction factor taking into account fluid property effects L ml pool length PT mL crest length PT mL pool len
40、gth PO mL width of one unit of Larinier fishpass L mn number of partitions POnllength scale factor POnVflow velocity scale POnQdischarge scale POnscale factor for length dimensions PTP height of the top baffle above the upstream bed L mP pool depth PT mQ discharge All m3/sQddesign discharge PT and P
41、O m3/sS bed slope of fishpass PO and LU burst velocity of fish PO m/sv flow velocity PT and PO m/sv1velocity of approach at tapping location L m/sVmean flow velocity PO m/sWL1upstream water level PO mWL2downstream water level PO mX distance to h1measurement section PT mu*CDe68standard uncertainty in
42、 discharge coefficient CDL, PT and PO %u*buncertainty in the gauging structure breadth measurement L, PT and PO %u(E) absolute uncertainty in gauge/head zero L, PT and PO m or mmu*H1euncertainty in the total head measurement L, PT and PO %uh1absolute uncertainty in the measured upstream head L, PT a
43、nd PO m or mmU*fpoverall uncertainty in fish pass flow L, PT and PO %U*fmsoverall uncertainty in flow measurement structure L, PT and PO % ISO 2015 All rights reserved 3BS ISO 26906:2015ISO 26906:2015(E)Symbol Term UnitU*ccombined overall uncertainty in fish pass and flow measurement structure flows
44、 L, PT and PO%Yddownstream water depth, related to upstream bed level PO mY0upstream water depth, related to upstream bed level PO m angle of V-shape PT degherror in measurement of h1PT mh drop over the fishpass for modular flow PT mhhead drop per pool PO mhddesign head drop per pool PO mt pool drop
45、 PT m5 PrincipleThe discharge over a flow measurement structure is a function of the upstream head (plus a measure of the downstream head in the case of those structures designed to operate in the non-modular flow range). When a fishpass is placed alongside a flow gauging structure, an additional fl
46、ow path is created. In certain circumstances, where the fishpass has a well-defined hydrometric calibration, total flows and uncertainties may be calculated. Thus the fishpass becomes an integral part of the flow measurement system. This International Standard provides the necessary design and perfo
47、rmance information for this type of arrangement.6 InstallationNOTE General requirements of combined flow measurement structure and fishpass installations are given in the following clauses.6.1 Requirements for gauging structure and fishpass installationsNOTE Requirements for the installation of meas
48、uring structures are given in the appropriate International Standard (see Clause 2 and the Bibliography). There is much in common between the different structures and the requirements, which can also be applied to flow measurement structure and fishpass installations, and are summarized in the follo
49、wing clauses.6.1.1 Selection of site6.1.1.1 A preliminary survey shall be made of the physical and hydraulic features of the proposed site, to check that it conforms (or may be made to conform) to the requirements necessary for flow determination by a structure, or combination of structures.6.1.1.2 Particular attention shall be paid to the following features when investigating a site: at existing meas
