THE WAMI RIVER INITIAL ENVIRONMENTAL FLOW ASSESSMENT Synthesis Report, June 2008 WAMI RIVER INITIAL ENVIRONMENTAL FLOW ASSESSMENT TEAM Project leaders: Mr. Julius Sarmett Dr. Elizabeth Anderson Basin Water Officer Deputy Director Wami-Ruvu Basin Water Office Global Water for Sustainability Program Tanzania Ministry of Water Florida International University, USA Ms. Appa Mandari WADA project coordinator Tanzania Coastal Management Partnership Scientific experts: Wami-Ruvu Basin Water Office: Mr. Mligo Cosmos, Riparian Specialist Mr. Ernest Lema University of Dar es Salaam Project Coordinator Ms. Pendo Hyera, Sociologist Eng. M.D. Rukiko Wami-Ruvu Basin Water Office Project Coordinator Dr. Phillip Mwanukuzi, Geomorphologist Eng. Misigaro Kigadye University of Dar es Salaam Project Coordinator Dr. P. M. Ndomba, Hydraulic Engineer Mr. Ebbo Makalinga University of Dar es Salaam Project Assistant Dr. Rashid Tamatamah, Aquatic Ecologist University of Dar es Salaam Project Assistant: Catherine McNally Dr. Patrick Valimba, Hydrologist Doctoral Student University of Dar es Salaam University of Rhode Island, USA ii TABLE OF CONTENTS FOREWORD................................................................................................................. IV ACKNOWLEDGEMENTS............................................................................................... V LIST OF TABLES.......................................................................................................... VI LIST OF FIGURES........................................................................................................ VI EXECUTIVE SUMMARY.................................................................................................1 CHAPTER 1: INTRODUCTION.......................................................................................2 CHAPTER 2: THE WAMI RIVER SUB-BASIN: PAST AND PRESENT .........................10 CHAPTER 3: RESULTS OF FIELD STUDIES (2007) AT ENVIRONMENTAL FLOW ASSESSMENT SITES.......................................................................................25 CHAPTER 4: THE WAMI INITIAL ENVIRONMENTAL FLOW ASSESSMENT: PROCESS AND PRODUCTS............................................................................57 CHAPTER 5: CONCLUSIONS AND THE FUTURE OUTLOOK FOR THE WAMI RIVER SUB-BASIN .......................................................................................................70 REFERENCES..............................................................................................................75 APPENDIX 1: RECOMMENDED ENVIRONMENTAL MANAGEMENT CATEGORIES FOR EFA STUDY SITES...................................................................................77 APPENDIX 2: DATA UNCERTAINTIES AND RESEARCH PRIORITIES FOR FIVE STUDY SITES IN THE WAMI RIVER SUB-BASIN ............................................84 APPENDIX 3: FLOW ASSESSMENT FORMS FROM DECEMBER 2007 WORKSHOP ..........................................................................................................................90 iii FOREWORD Environmental Flow Assessment (EFA) is a new concept in Tanzania, but the role it plays in enabling integrated management of water resources is vital and should not be underestimated. The overall objective of an EFA is to develop quantitative guidelines for management of flows in rivers. An EFA is a tool used to draw the line between the amount of water that can be withdrawn from a river for human uses and the amount of water that the river needs to sufficiently maintain ecosystems. The emergent product is a quantitative estimate of the flow needs of the river and, in some cases, a consideration of the different human uses of water. Tanzania’s new water policy, by according the environment second priority as a user of water, provides the necessary legal backing for the EFA process. However, to date few rivers in Tanzania have been subjected to this detailed assessment. As described in this document, the Wami project is a pioneering EFA effort as a Tanzanian-led project and a proactive approach to management. It falls alongside other notable EFA efforts in the country, such as those in the Pangani, Mara, and Rufiji (Ruaha) river basins. With this initiative the Country has substantively benefited in terms of the findings that have accrued out of this project and the experience gained by our staff who were involved in the study. It is recommended therefore that water resources experts should spend some time exploring this report and make use of the findings to establish a study similar to this one for river systems in the entire country. I also urge the policy makers to make use of EFA findings as a decision-making tool for sustainable development of the society which depends on water resources as a source of livelihood. We should not wait until when all rivers have gone dry and the ecosystem collapse, since it is difficult, costly and time consuming to reverse the process, even if we would wish doing it. Julius D. Sarmett Wami/Ruvu Basin Water Officer 4 June 2008 iv ACKNOWLEDGEMENTS The Wami River Initial Environmental Flow Assessment (Wami IEFA) project was a process-based approach to determining flow requirements of the Wami River and its related ecosystems, as a means for enabling more sustainable water management in the Wami River Sub-Basin. This project would not have been possible without the dedication, hard work, and strong collaborative spirit of the Wami IEFA team. In particular, the scientific experts should be acknowledged for the energy and professionalism that they brought to the project and the entire team benefited from their generosity in sharing their knowledge. Special thanks go to the University of Dar es Salaam for permitting their involvement. The staff of the Wami-Ruvu Basin Water Office (WRBWO) should also be recognized for their enthusiasm and support to the project, and for facilitating access to valuable information about the Wami River Sub-Basin, without which the flow assessments would not have been possible. It is hoped that the WRBWO staff have increased their knowledge of river ecosystems through participation in this project, and that the scientific experts now have a greater understanding of the decisions facing water managers in Tanzania following their collaboration with the WRBWO. Logistical and administrative support in Tanzania was provided by the Wami-Ruvu Basin Water Office, as well as the Tanzania Coastal Management Partnership (TCMP). The staff members of TCMP deserve acknowledgements for their efforts to offer guidance on the Wami IEFA project (Jeremiah Daffa, Baraka Kalangahe), to coordinate the Wami IEFA project with other related activities (Appa Mandari), and to assist with management funds for the project (Esther Kapinga). The drivers and other support staff of TCMP also provided needed assistance to the Wami IEFA project. Special thanks go to the Tanzanian Ministry of Water, in particular Washington Mutayoba, Elizabeth Nkini, and Saidi A. Faraji, for their support of the Wami IEFA initiative from beginning to end. It is hoped that this project and the lessons learned from the Wami IEFA provide an example for other basin water offices in Tanzania. Thanks also go to Saadani National Park, in particular the park ecologist, Halima Ramadhani, who lent valuable support as a voice for the park and the Wami River estuary. Funding for this project was provided by the US Agency for International Development (USAID) and the Coca-Cola Company, as a component of the Tanzania Water and Development Alliance (WADA). We are grateful to the Coastal Resources Center at the University of Rhode Island, in particular Don Robadue and Jim Tobey, for the initial invitation to work with the Tanzania WADA program and for continued support throughout the project. The USAID Global Water for Sustainability Program, based at Florida International University, was also instrumental in providing complementary financial and administrative support, as well as technical guidance on the project. Special thanks go to Andrea Lamelas and Dr. Michael McClain at Florida International University. Dr. Jay O’Keeffe of the UNESCO-IHE was helpful with ideas on how to approach the Wami River project during its planning phases. Amanda Subalusky and John Stiefel provided valuable editorial assistance in the preparation of documents. We also would like to specially acknowledge Michael McClain, Jeremiah Daffa and Jim Tobey, who provided the initial impetus and idea for this project following a May 2006 visit to the Wami River, and who supported the Wami IEFA team throughout the project. v LIST OF TABLES Table 1.1. The Wami/Ruvu Basin Water Office: Vision, Mission, Core Values, and Main Responsibilities....................................................................................................5 Table 1.2. The Steps Process for the Wami Initial Environmental Flows Assessment .....7 Table 2.1. Major rivers of the Wami River Sub-Basin. ...................................................12 Table 2.2. Number of endemic vertebrate and tree species in Eastern Arc Forests in the Wami River Sub-Basin (Source: Burgess, 2005) ...............................................17 Table 2.3. Fishes reported from the Wami River and its tributaries, based on collections by Bernacsek 1980, Eccles 1992, and Tamatamah 2007. ........................................19 Table 2.4: Distribution of population by some districts in Wami River ............................22 Table 2.5. River resource use in the Wami River