Agricultural development in the Central Ethiopian Rift valley: A desk-study on water-related issues and knowledge to support a policy dialogue Huib Hengsdijk1 & Herco Jansen2 1 Plant Research International, Wageningen 2 Alterra-ILRI, Wageningen Plant Research International B.V., Wageningen January 2006 Note 375 © 2006 Wageningen, Plant Research International B.V. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, without the prior written permission of Plant Research International B.V. Plant Research International B.V. Address : Droevendaalsesteeg 1, Wageningen, The Netherlands : P.O. Box 16, 6700 AA Wageningen, The Netherlands Tel. : +31 317 47 70 00 Fax : +31 317 41 80 94 E-mail :
[email protected] Internet : www.pri.wur.nl Alterra-ILRI Address : Droevendaalsesteeg 3, 6708 PB WAGENINGEN, The Netherlands P.O. Box 47, 6700 AA Wageningen, The Netherlands Tel. : +31 317 4 74700 Fax : +31 317 419000 E-mail :
[email protected] Internet : ww.alterra.wur.nl Table of contents page Summary 1 1. Introduction 3 2. Physical setting 5 2.1 Location and topography 5 2.2 Climate 7 2.3 Land use 7 2.4 Surface water 8 2.5 Groundwater 9 2.6 Ecology 10 3. Water resources assessment 13 3.1 Lake Ziway 13 3.1.1 Water quantity 13 3.1.2 Water quality 13 3.2 Lake Abyata 14 3.2.1 Water quantity 14 3.2.2 Water quality 14 3.3 Groundwater 15 4.