ISO INTERNATIONAL STANDARD 11657 First edition 2014-07-01 Hydrometry - Suspended sediment in streams and canals Determination of concentration by surrogate techniques Hydrométrie-Sédiments en suspension dans les cours d'eau et dans les canaux -Détermination de la concentration par des techniques desubstitution Reference number IS0 11657:2014(E) ISO @ IS0 2014 I without license from IHS Not for Resale IS0 11657:2014(E) COPYRIGHTPROTECTEDDOCUMENT @ IS0 2014 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, 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 ISO's member body in the country of the requester. ISO copyright office Case postale 56:CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyright@iso.org Web www.iso.org Published in Switzerland @ IS0 2014 - All rights reserved No reproductic networking permited without license from IHS Not for Resale IS0 11657:2014(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. ..1 2 Normative references ..1 3 Terms and definitions ..1 4 Measuring principles .2 4.1 Transmission .2 4.2 Scattering. .2 4.3 Transmission - Scattering .3 4.4 Diffraction .3 5 Properties of sediment of importance for sediment surrogate techniques .3 5.1 General 3 5.2 Particle size .4 5.3 Particle colour 4 6 Methods for determination of suspended sediment concentration by surrogate techniques .4 6.1 General. 4 6.2 Bulkoptics .4 6.3 Laser diffraction (LD) .5 6.4 Acoustic back scatter (ABS) .5 7 Calibration and validation .6 Annex A (informative) Determination of the concentration of suspended sediment by optical techniques .9 Annex B (informative) Determination ofthe concentration of suspended sediment by laser diffraction technique. .12 Annex C (informative) Determination of the concentration of suspended sediment by acoustic backscatter .14 Bibliography .18 iii se with IS nout license from IHS Not for Resale