Guidelines on Environmental Flows (EFlows) Assessments for the Western Indian Ocean (WIO) region i Check that this page complies with most recent approved UNEP format Published by the United Nations Environment Programme/Nairobi Convention Secretariat. Copyright © Nairobi Convention 2019. All rights reserved: The findings, interpretations and conclusions expressed herein are those of the authors and do not necessarily reflect the views of the Contracting Parties to the Nairobi Convention. Rights and Permissions: The information in this report is copyrighted, therefore, copying and/or transmitting portions of this report without permission of the Nairobi Convention may be a violation of applicable law. However, the Nairobi Convention encourages dissemination and use of the materials in this report. Disclaimer: This publication has been produced with the kind assistance of the various governments, United Nations Agencies, Non-Governmental Organizations, Civil Society Organizations, as well as of individuals with financial support from the Global Environment Facility (GEF). However, the report is copyrighted entirely to the Nairobi Convention. Compiled and prepared by: Cate Brown and Jackie King, with contributions from Lara Van Niekerk and Susan Taljaard. Citation: UNEP-Nairobi Convention/WIOMSA (2019). Guidelines on Environmental Flows (EFlows) Assessments for the Western Indian Ocean (WIO) region. UNEP, Nairobi, XXXpp. ISBN: XXXX ii Table of Contents 1 Introduction ................................................................................................................................................ 1 1.1 Rationale, mandate and process followed in the development of the guidelines .......................... 1 1.2 Structure of the guidelines ................................................................................................................. 2 1.3 Definitions............................................................................................................................................ 3 2 Environmental Flows .................................................................................................................................. 4 2.1 The need for EFlows ............................................................................................................................ 5 2.2 The effects of human developments on rivers and estuaries .......................................................... 6 2.3 Climate change and EFlows ................................................................................................................ 8 2.4 Negotiating objectives for river and estuarine ecosystem status .................................................... 9 2.5 An integrated river basin management approach .......................................................................... 10 3 EFlows Assessments ................................................................................................................................. 12 3.1 EFlows Assessment methods ............................................................................................................ 12 3.2 Trends in EFlows Assessments in the WIO region ........................................................................... 19 3.3 Information provided by EFlows Assessments ................................................................................ 21 3.3.1 EFlows information to support the sustainability of marine ecosystems .............................. 23 4 Undertaking an EFlows Assessment ........................................................................................................ 26 4.1 Nature of the assessment, budget, method and team ................................................................... 26 4.1.1 Purpose and scope .................................................................................................................... 26 4.1.2 Budget ....................................................................................................................................... 27 4.2 Select an appropriate EFlows Assessment method ........................................................................ 29 4.2.1 Supporting models .................................................................................................................... 31 4.2.2 Consideration for the selection of methods for WIO EFlows Assessments........................... 31 4.3 EFlows Assessment team .................................................................................................................. 32 4.4 Spatial and temporal units of assessment ....................................................................................... 34 4.4.1 Site selection ............................................................................................................................. 34 4.4.2 Time-scales for analysis ............................................................................................................ 35 4.4.3 Baseline conditions ................................................................................................................... 37 iii 4.5 Stakeholder engagement .................................................................................................................. 37 4.6 Scenarios ............................................................................................................................................ 39 4.7 Biophysical and social indicators ...................................................................................................... 40 4.7.1 Mapping indicator links ............................................................................................................ 41 4.8 Data requirements ............................................................................................................................ 42 4.8.1 Physical/chemical ...................................................................................................................... 46 4.8.2 Biology ....................................................................................................................................... 48 4.8.3 Social .......................................................................................................................................... 48 4.9 Field visits .......................................................................................................................................... 49 4.10 Set-up and calibrate EFlows models ................................................................................................ 49 4.11 Analyse the scenarios........................................................................................................................ 50 4.12 Reporting ........................................................................................................................................... 52 4.12.1 Other deliverables .................................................................................................................... 52 5 Managing data limitations ........................................................................................................................ 54 6 Mainstreaming the uptake of EFlows Assessments ................................................................................ 56 6.1 Deciding on EFlows allocations ........................................................................................................ 56 6.2 Harmonizing policies and working with government agencies ...................................................... 57 6.3 Building managerial and technical capacity in E-Flows Assessment .............................................. 58 6.4 E-Flows information systems ............................................................................................................ 59 6.5 Funding to support EFlows ............................................................................................................... 60 7 References................................................................................................................................................. 62 iv List of Tables Table 3.1 Commonly-used EFlows Assessment methods for rivers .......................................................... 15 Table 3.2 Commonly-used EFlows Assessment methods for estuaries ..................................................... 16 Table 3.3 Actions required for including the nearshore marine environment into an EFlows Assessments ....................................................................................................................................................... 18 Table 3.4 Definitions of the ecological condition categories ..................................................................... 22 Table 3.5 Strengths and weakness of categories of EFlows Assessment methods................................... 24 Table 4.1 Personnel time (days) for different resolution levels of flow assessments per river , excluding travel and stakeholder liaison time, and disbursements. These are estimates only. ............... 28 Table 4.2 Personnel time (days) for different resolution levels of flow assessments per estuary, excluding travel and stakeholder liaison time, and disbursements. These are estimates only. ............... 28 Table 4.3 Decision matrix for selection of a suitable EFlows Assessment method................................... 30 Table 4.4 Potential members of