WATER RESOURCES PROTECTION POLICY IMPLEMENTATION

RESOURCE DIRECTED MEASURES FOR PROTECTION OF WATER RESOURCES

RIVER ECOSYSTEMS

Department of Water Affairs and Forestry

South Africa

REPORT NUMBER:N/29/99

STATUS:VERSION 1.0

DATE:24 SEPTEMBER 1999

SENIOR AUTHORS (in alphabetical order):

Dr A Bath, Ninham Shand Consulting Engineers

Dr CJ Kleynhans, Department of Water Affairs and Forestry

Ms MD Louw, IWR Environmental

Dr H MacKay, Department of Water Affairs and Forestry

Mr JN Rossouw, Ninham Shand Consulting Engineers

Published by

Department of Water Affairs and Forestry

Private Bag X313

Pretoria

0001

Republic of South Africa

Tel +27 (0)12 336 7500

ISBN X-XXXX-XXXX-X (Set)

ISBN X-XXXX-XXXX-X (Volume 5)

Copyright reserved

No part of this publication may be reproduced in any manner without full acknowledgement of the source

This document should be cited as:

Department of Water Affairs and Forestry (1999). Resource Directed Measures for Protection of Water Resources. Volume 3: River Ecosystems Version 1.0, Pretoria.

Senior Editor:

Dr H M MacKay, Department of Water Affairs and Forestry, South Africa

Produced by:

Institute for Water Quality Studies

Department of Water Affairs and Forestry

Private Bag X313

Pretoria 0001

This document is one of a series of 15 volumes comprising the set: Resource Directed Measures for Protection of Water Resources.

Volume 1:Resource Directed Measures - Summary of Policy (to be included in Version 1.1)

Volume 2:Resource Directed Measures - Integrated Manual

Volume 3:Resource Directed Measures - River Ecosystems

Volume 4:Resource Directed Measures - Wetland Ecosystems

Volume 5:Resource Directed Measures - Estuarine Ecosystems

Volume 6:Resource Directed Measures - Groundwater Component

Volume 7:Resource Directed Measures - Basic Human Needs (to be included in Version 1.1)

Volume 8:Resource Directed Measures - Classification System for Water Resources

Volume 9:Resource Directed Measures - Study Manager’s Manual (to be included in Version 1.1)

Volume 10:Resource Directed Measures - Implementation Strategy (to be included in Version 1.1)

Volume 11:Resource Directed Measures - Crocodile River Pilot Study 1998 (to be included in Version 1.1)

Volume 12:Resource Directed Measures - Pienaars River Pilot Study 1999 (to be included in Version 1.1)

Volume 13:Resource Directed Measures - Communication Strategy (to be included in Version 1.1)

Volume 14:Resource Directed Measures - Capacity Building Strategy (to be included in Version 1.1)

Volume 15:Resource Directed Measures - Project Management Summary (to be included in Version 1.1)

Resource Directed Measures for Protection of Water Resources: River Ecosystems

WATER RESOURCE PROTECTION AND ASSESSMENT POLICY IMPLEMENTATION PROCESS

RESOURCE DIRECTED MEASURES FOR PROTECTION OF WATER RESOURCES: RIVER ECOSYSTEMS COMPONENT

Report Number:N/29/99

Team Leaders:Ms MD Louw, IWR Environmental

Mr JN Rossouw, Ninham Shand Consulting Engineers

Senior Authors:Dr A Bath, Ninham Shand Consulting Engineers

Dr CJ Kleynhans, Department of Water Affairs and Forestry

Ms MD Louw, IWR Environmental

Dr H MacKay, Department of Water Affairs and Forestry

Mr JN Rossouw, Ninham Shand Consulting Engineers

Editor:Dr Heather MacKay, Department of Water Affairs and Forestry

Ms L Guest, Guest Environmental Management

Version:1.0

Date:24 September 1999-10-12

D:\..\f_rdm_october\rivers\version 1.0\riv_intro_version1.0.doc

Acknowledgements

The following persons and organisations are thanked for their contributions to this project.

PROJECT TEAM

Project Manager:

Dr H M MacKay, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Project Co-ordinator:

Mr D F Grobler, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Project Administration:

Ms O Shapo, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Ms C Nkwentsha, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Sub-Project Team Leaders:

Dr J B Adams, University of Port Elizabeth

Dr A Bath, Ninham Shand

Mr T Duma, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Mr A Duthie, Oryx Environmental

Ms S Fowkes, Metaplan

Ms T Greyling, Manyaka Greyling Meiring

Ms L Hill, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Ms M D Louw, IWR Environmental

Mr J N Rossouw, Ninham Shand

Mr D J Roux, Environmentek, CSIR

Mr R Parsons, Parsons & Associates

Ms C Thirion, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Ms B C Weston, Social and Ecological Services, Department of Water Affairs and Forestry

Specialist Team Members (River Ecosystems):

Dr P J Ashton, Environmentek CSIR

Dr A Bath, Ninham Shand Consulting Engineers

Dr A Birkhead, Streamflow Solutions

Dr J Day, University of Cape Town

Ms L Hill, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Mr B Hohls, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Mr G Huggins, IWR Environmental

Prof D Hughes, Institute for Water Research

Mr S Jooste, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Mr N Kemper, IWR Environmental

Ms V Kilian, Department of Water Affairs and Forestry

Dr C J Kleynhans, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Ms M D Louw, IWR Environmental

Dr H MacKay, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Prof J O’Keeffe, Institute for Water Research

Dr C G Palmer, Institute for Water Research

Ms L Rossouw, MetsiQual

Mr J N Rossouw, Ninham Shand Consulting Engineers

Dr D J Roux, Environmentek CSIR

Dr P-A Scherman, Institute for Water Research

Ms R Tharme, Southern Waters

Mr P van der Merwe, Department of Water Affairs and Forestry

Dr R Wadeson, IWR Environmental

STEERING COMMITTEE

Dr H R van Vliet (Chair), Chief Director: Scientific Services, Department of Water Affairs and Forestry

Mr J van Rooyen, Department of Water Affairs and Forestry

Mr H Karodia, Department of Water Affairs and Forestry

Mr M Warren, Department of Water Affairs and Forestry

Mr P Viljoen, Department of Water Affairs and Forestry

Dr S Mitchell, Water Research Commission

Mr G Cowan, Department of Environment Affairs and Tourism

Mr W S Rowlston, Department of Water Affairs and Forestry

Mr P van Niekerk, Department of Water Affairs and Forestry

Mr E Braune, Department of Water Affairs and Forestry

Mr E Nel, Department of Water Affairs and Forestry

Mr G McConkey, Department of Water Affairs and Forestry

Mr Kelvin Legge, Department Of Water Affairs and Forestry

EDITING TEAM

Dr H MacKay, Institute for Water Quality Studies, Department of Water Affairs and Forestry

Ms L Guest, Guest Environmental Management

Dr G Pegram, Pula Strategic Resource Management

Ms M de Lange, Socio Technical Interfacing

Ms B Weston, Social and Ecological Services, Department of Water Affairs and Forestry

Preface

This set of documents on Resource Directed Measures (RDM) for protection of water resources, issued in September 1999 in Version 1.0, presents the procedures to be followed in undertaking preliminary determinations of the class, Reserve and resource quality objectives for water resources, as specified in sections 14 and 17 of the South African National Water Act (Act 36 of 1998).

The development of procedures to determine RDM was initiated by the Department of Water Affairs and Forestry in July 1997. Phase 3 of this project will end in March 2000. Additional refinement and development of the procedures, and development of the full water resource classification system, will continue in Phase 4, until such time as the detailed procedures and full classification system are ready for publication in the Government Gazette.

It should be noted that until the final RDM procedures are published in the Gazette, and prescribed according to section 12 of the National Water Act, all determinations of RDM, whether at the rapid, the intermediate or the comprehensive level, will be considered to be preliminary determinations.

Version 1.0 of the RDM procedures is for internal use within the Department of Water Affairs and Forestry. It is a set of working documents which will be updated on a regular basis. This version retains editor’s comments in certain places in the text.

Version 1.1 is expected to be finalised and published in December 1999, and will be released for public comment and discussion.

All technical queries and comments related to Version 1.0 should be addressed to:

Dr H M MacKay

Department of Water Affairs and Forestry

Private Bag X313

Pretoria 0001

South Africa

Tel +27 12 336 8222

Fax+27 12 336 8678

email

Abbreviations

DWAF-Department of Water Affairs and Forestry

EMC -Ecological Management Class

IFR-Instream Flow Requirements

RDM-Resource Directed Measures

Table of Contents

Section A:Resource Directed Measures for River EcosystemsA2

A.1Different levels of RDM determinationsA2

A.2The generic RDM methodologyA3

Section B:Resource Directed Measures for River Ecosystems

(to be included in version 1.1)

Section C:Procedure for Desktop Estimate of the Water Quantity Component

of the Ecological ReserveC2

C.1What is in this sectionC2

C.2Desktop Estimate of the Ecological Management ClassC3

Section D:Procedure for Rapid Determination of RDM for River EcosystemsD2

D.1What is in this sectionD2

D.2IntroductionD2

D.3Determination of the ecological management classD3

D.4Quantification of the Water Quantity Component of the Ecological ReserveD4

D.5Quantification of the Water Quality Component of the Ecological ReserveD5

Section E:Procedure for Intermediate Determination of RDM for River EcosystemsE2

E.1What is in this sectionE2

E.2Overview of tasks in intermediate determination of RDME2

Section F:Methodology for Comprehensive Determination of RDM for river ecosystemsF2

F.1OverviewF2

Appendices

Appendix R1:Preliminary Ecoregion Classification System for South AfricaR1/2

Appendix R2:Stream ClassificationR2/2

Appendix R3:Desktop Level Estimate of the Present Ecological Status for use

in the National Water Balance ModelR3/2

Appendix R4:Intermediate Habitat Integrity Assessment

(for use in the rapid and intermediate habitat assessments)R4/2

Appendix R5:Habitat Integrity Assessment for the Comprehensive Determination

of the Ecological ReserveR5/2

Appendix R6:Procedure for assessing the present ecological statusR6/2

Appendix R7:Assessment of Ecological Importance and SensitivityR7/2

Appendix R8:Determination of the Social Importance of a Water ResourceR8/2

Appendix R9:Incorporation of Economic Consideration into the RDM Determination:

A Proposed Conceptual ApproachR9/2

Appendix R13:A Decision Support System for an Initial Low-Confidence Estimate

of the Quantity Component of the Ecological Reserve for RiversR13/2

Appendix R16:Providing Hydrological Information and Data Analysis Tools

for the Determination of Ecological Instream Flow Requirements

for South African RiversR16/2

Appendix R17:The Procedure for Generating Hydraulic Information and Intermediate

and Comprehensive Ecological Reserves (Quantity)R17/2

Appendix R18:Role of Geomorphology in Intermediate Ecological Reserve DeterminationR18/2

Appendix R19:The Procedure for Generating Riparian Vegetation Information for the

Comprehensive and Intermediate Reserve (Quantity)R19/2

Appendix R20:The Use of Ecological Information on Fish in the Specification

of the Flow Component of the Reserve (Desktop, Rapid, Intermediate

and Comprehensive DeterminationsR20/2

Appendix R21:The Procedure for Generating Aquatic Invertebrate Information

for the Intermediate and Comprehensive Ecological Reserve (Quantity)

for RiversR21/2

Appendix R22:Procedure for Selecting Sites in Intermediate and Comprehensive

Determination of the Ecological Reserve (Water Quantity Component)R22/2

Appendix R23:Resource Quality Objectives: Determination of Habitat Integrity ObjectivesR23/2

Appendix R24:Analysis of Previous IFR ResultsR24/2

Appendix R25:Giving Effect to the Reserve: Yield Modelling and Design

of System Operating RulesR25/2

Appendix R29:Using Ecological Management to derive integrated Resource Quality

Objectives and the Ecological Reserve for Water ResourcesR29/2

Appendix R30:Breakdown and Scheduling of Tasks for Intermediate RDM DeterminationR30/2

Appendix 31:Design of Post – RDM Monitoring ProgrammesR31/2

Figures

Figure A1:Generic procedure for determination of Resource Directed Measures

for aquatic ecosystemsA4

Figure C1:Procedure followed in the determination of the AEMCC4

Figure C2: Flow diagram indicating the sequence of steps proposed for the determination

of the attainable ecological management class in the determination of the WBDE.C7

Figure D1: Procedure followed in the determination of the AEMCD4

Figure E1: Task flow for intermediate RDM determinationE3

Figure E2: Output of the IFR model as a time seriesE22

Figure E3: Output of an IFR workshop illustrated as a FDC

(Note all numbers on axis are hypothetical and differ from river to river)E23

Tables

Table A1: Levels of RDM procedures for various levels of RDM determinationsA2

Table A2: Master table of differences/similarities between RDM levels, broken down by stepsA22

Table C1: Ecological importance and sensitivity categories.C9

Table C2: Biotic determinants (instream and riparian) for assessment of ecological importance

and sensitivity.C9

Table C3: Habitat (instream and riparian) determinants for assessment of ecological importance

and sensitivity.C11

Table C4: Confidence ratings for biotic and habitat determinants.C13

Table C5: Ecological importance and sensitivity categories. Interpretation of median scores

for biotic and habitat determinants.C14

Table C6: Default ecological management classes for rivers (adapted from Kleynhans 1996

and Kleynhans et al. 1998).C15

Table C7: The relationship between ecological importance and sensitivity categories and default

ecological management classes.C15

Table C8: Default ecological status classes (adapted from Kleynhans 1996).C16

Table C9: The relationship between default ecological management classes

and default ecological status classes.C16

Table C10: Attributes to be assessed for determination of present ecological status.C17

Table C11: Scoring and rating guidelines for present ecological status estimation

(adapted from Kleynhans 1996).C18

Table C12: The assessment of the restoration potential of different aspects of the present ecological

status class of rivers, as a basis for deriviation of the AEMC.C20

Table D1: Rapid present status assessment for total dissolved salts (TDS)D7

Table D2: Rapid present status assessment for pH in rivers.D8

Table D3: Rapid present status assessment for dissolved oxygen.D8

Table D4: Rapid present status assessment using the un-ionised ammonia concentration to assign

assessment categories for riversD9

Table D5: Rapid present status assessment based on orthophosphate as a percentage of the total

phosphorus contentD10

Table D6: Rapid present status assessment of nutrient content based on the N-P ratio

(using TIN and TP)D10

Table D7: Rapid present status assessment of nutrient status based on N-P ratio

(using only orthophosphate data)D10

Table D8: Documentation of present ecological status assessment – exampleD11

Table D9: Guide for rapid determination of the ecological Management Classes

(water quality component) based on the ecological management class for the biota. D12

Table D10: Matrix for determination of the ecological Reserve (water quality)for system variables.D13

Table D11: Allowable deviation from the baseline water quality for selected ecological

management classes (water quality)D13

Table D12: Nutrient water quality ranges for selected ecological management classes

(water quality).D14

Table E1: Generally applicable reference conditions for nutrientsE12

Table E2: Present status assessment categories for total dissolved salts (TDS)E13

Table E3: Present status assessment for pH in rivers.E14

Table E4: Present status assessment for dissolved oxygen.E14

TableE 5: Present status assessment for nutrients using the un-ionised ammonia concentrationE15

Table E6: Present status assessment of nutrients based on orthophosphate as a percentage

of the total phosphorus contentE15

Table E7: Present status assessment of nutrients based on the N-P ratio (using TIN and TP)E16

Table E8: Present status assessment of nutrients based on N-P ratio

(using only orthophosphate data)E16

Table E9: Documentation of present ecological status - exampleE17

Table E10: General assessment categories for ecological integrity.E18

Table E11: Tabulated output of the specialist workshop, providing the design IFRs.E21

Table E12: Guide for intermediate determination of ecological management classes

(water quality) based on the ecological management class assigned for the biota..E24

Table E13: System variable matrix for the assignment of the Reserve.E24

Table E14: Matrix for determination of the ecological Reserve (water quality) for pH

and dissolved oxygen.E25

Table E15: Allowable deviation from of water temperature and TSS from reference conditions

for selected ecological management classes (water quality).E25

Table E16: Nutrients water quality ranges for selected ecological management classes

(water quality).E26

References

Glossary

1

Department of Water Affairs and Forestry, South Africa

Version 1.0: 24 September 1999