WHAT ARE ENVIRONMENTAL FLOWS?Background and rationale

Jay O’Keeffe

WWF Professor of Freshwater Ecosystems

UNESCO-IHE,

Delft, The Netherlands

PURPOSE OF THE NEXT DAY AND A HALF

• To introduce the concept of environmental flows• To describe some of the assessment methods• To identify different regional requirements• To discuss the role of WWF in promoting

environmental flows

Environmental flows workshop, 11-12th March11th March, Morning09:00 What are environmental flows? Background and rationale (O’Keeffe, McClain)

10:00 Assessment methods for rivers (O’Keeffe)

11:00 Tea/coffee

11.15 Policy, legislation and social context for environmental flows (v d Heydon, Ombara)

12.30 Case study – Rio Conchos (Arias, Barajas)

13.30                    Lunch 

11th March, Afternoon15:00 Case studies – Mara River,Kafue River (Ombara, McClain, Leenen)

16.00 Tea/coffee

16.15 Case study – Rio Grande (Bardwell)

16.45            Discussion – the need for environmental flows in different

regions, appropriate methods and implementation (O’Keeffe, facilitator)

17:30 Close.

 

12th March, Morning 09:00 Practical assessment: Small groups apply the BBM to a site on the Rio Conchos

11.15 Tea/coffee

11.30 Discussion: Identify priorities for implementing

environmental flows in different river basins.

Training needs and the role of WWF (Pittock/Kuiper, facilitators)

12:30 Close

About 0.3 m3sec-1

WHAT ARE ENVIRONMENTAL FLOWS?

The quality, quantity and distribution of water required to maintain the components, functions and processes of aquatic ecosystems on which people depend.

The process of assessing an EWA will require a societal judgement about the state in which an ecosystem should be maintained.

The quality, quantity and distribution of water required for any aquatic ecosystem will depend on the environmental objectives set for that system.

WHAT ARE ENVIRONMENTAL FLOWS?

The quality, quantity and distribution of water required to maintain the components, functions and processes of aquatic ecosystems on which people depend.

The process of assessing an EWA will require a societal judgement about the state in which an ecosystem should be maintained.

The quality, quantity and distribution of water required for any aquatic ecosystem will depend on the environmental objectives set for that system.

Water quantityand quality

Rivers

Estuaries Wetlands

Groundwater

Lakes

COMMON MISCONCEPTIONS

Environmental flow allocation:• is water wasted water on bugs and fish• is water for “The Ecology” in competition with water

for “Beneficial Uses”• costs a lot to implement• is designed to maintain rivers in a natural condition

Environmental flows are all about balancing

sustainable use and protection of water resources

  

Economic gain

Environmental degradation

% MAR abstracted 0100

%

0

100

Large gains

Low env. costs

First 30%

Very small gains

Very rapidIncrease

Last 30%

COMMERCIAL FOREST

HEALTH ISSUES

ALIEN PLANTS & ANIMALS

SEWAGE

IRRIGATION

CHANNEL MODIFICATION

WATER ABSTRACTION

WATER QUALITY

TEMPERATURE

SEASONAL CHANGES

SENSE OF PLACE

RECREATION & TOURISM

MINING

INDUSTRY

URBANCULTURAL/RELIGIOUS

FLOOD CONTROL

HISTORICAL

GOODSSUBSISTENCE

WATER SUPPLY

GOODS & SERVICES

MEDICAL PLANTS

SELF-PURIFICATION

1O PRODUCTION

Natural

Good Fair

Poor

Protected Unacceptable

Good Fair

 

WATER RESOURCE CLASSIFICATION

Questions that have to be answered to provide realistic Environmental Water

Requirements:“What was the system like?”

Reference Conditions“What is it like now?”

Present Ecological State“What condition would we like it to be in?”

Classification and Objectives“What flows and water quality are necessary to make or keep it as we

would like it to be?”Assessment of EWA

“How important is it?” (to achieve the environmental objectives)

Ecological Importance and Sensitivity“How much will it cost if the environmental

objectives are not met?”Cost/benefit Analysis

“How can the required flows be provided?”Implementation

“How will we know whether the objectives are being achieved?”

Monitoring

How do you go about assessing the water quantity necessary

for a river?

SEDIMENT

LOCAL SCALE PROCESSES

RIPARIAN ZONE

ORGANIC INPUTS

DEPTHSEEPAGE

FLOODPLAIN

WETLANDS

VELOCITY

HYPORHEOS

WETTED PERIMETER

1° PROD & DECOMPOSITION

COVER

TEMPORAL VARIATION

WET SEASON

VEGETATIONDRY SEASON

SEDIMENTATION &

SCOURING

DROUGHT

FLOOD

ENCROACHMENT

ONE YEAR

Natural flows

Environmental flows

FLOW

A) RIVER FLOWING THROUGH A CONSERVATION AREA

ONE YEAR

Natural flows

Environmental flows

FLOW

B) RIVER FLOWING THROUGH AN URBAN AREA

ONE YEAR

Natural flows

Environmental flows

FLOW

C) A SPRING-FED RIVER (LESS VARIABLE FLOW)

Natural flows

Environmental flows

ONE YEAR

FLOW

D) A TEMPORARY RIVER (NO FLOW IN THE DRY SEASON)

GENERIC TYPES OF ASSESSMENT

METHODOLOGY• Hydrology-based/Look-up table approaches• Extrapolation approach• Hydraulic rating methodologies• Habitat simulation methodologies• Holistic methodologies• “See what happens” method• “Upside down” instream flows approach• Burden of proof (Impairment of the public trust)

HYDROLOGYFlows in m3/sec

ECOLOGYHabitat types

Ecological processes

Indicator species

The Engineer The Ecologist

HYDRAULICSVelocity, Depth,

Substrate

Balance user and Balance user and environmental functionsenvironmental functions

Set environmental Set environmental objectives/limitsobjectives/limits

Learn to judge how far Learn to judge how far water resources can be water resources can be used before those limits used before those limits are exceeded are exceeded

Increase efficiency of water Increase efficiency of water supply and sanitationsupply and sanitation

Value ecosystem functionsValue ecosystem functions

Some Lessons:

http://www.waterandnature.org/flowlaunch.html

http://www.rivers.gov.au/publicat/research.htm Then click on:Environmental water allocation: principles, policies and practices

King JM; Tharme R; De Villiers MS (2000)Environmental flow assessments for rivers: Manual for the building block methodology. TT131/00.From: The Water Research Commission,

Private Bag X03, 0031 Rietfontein, Pretoria, South Africa  

Contact Numbers: Telephone: +27-12-330-0340Fax: +27-12-331-2565

For all three of these reports, go to ftp.ihe.nl.The username and password are both ftpftp.Open folder Jay and download the reports.

THANK

YOU

Wet Season Dry Season

Look-up Table

                

Figure 2 Flow requirements for drought years for all ecological categories

Hydrological Index302520151050

An

nu

al T

ota

l Re

qu

ire

me

nt

(% M

AR

) 25

20

15

10

5

0

 

Extrapolatio

n

Approach

Habitat

Simulatio

n

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

Ele

vatio

n (m

)

10 20 30 40 50 60 70Chainage (m)

IFR 2 : SKIETDRIFT - 1.48 m3/S

I FR 14 : Lower Buff alo 0.68 m3/S

Provide resourceeconomic consequences

Cost/Confidenceanalysis

Projectscope

Reserve ComponentsRivers, Groundwater,Estuaries, Wetlands

1. INITIATE RDM STUDY- STUDY AREA- RDM LEVEL & COMPONENTS- STUDY TEAM

RDM protocols

RDM levelRapid I, II, IIIIntermediateComprehensive

?

2. DEFINE RESOURCE UNITS

System operation

Select IFR sites

Geomorphologicalzonation

Ecoregions

3. DEFINE ECOLOGICALCATEGORIES (EC) AND

RECOMMEND

EC ClassificationReference conditionsPresent Ecological StateTrajectories of changeEcological Importance and SensitivitySocio/Cultural ImportanceConstraints(EC specialist meeting)

Stakeholder ProcessCapacity buildingEmpowering

4. QUANTIFY ECOLOGICALWATER REQUIREMENT(EWR) SCENARIOS

Apply Process(BBM, Stressor Response, DRIFT)(IFR specialist meeting)

Data OrganisationCollate existing dataCollect additional infoAnalyse info

5. ECOLOGICALCONSEQUENCES OF

OPERATIONAL SCENARIOS(quantity & quality)

YIELD CONSEQUENCES OFRESERVE

Define operationalscenarios

CatchmentSystem Analysis

Integration BHN &Reserve

components

Yield & stakeholderrequirements,

operational constraints

Stakeholder processScenario implications &

assessment

6. DWAF MANAGEMENTCLASS DECISION MAKING

PROCESS

Information on categoriesother than Ecological, i.e.domestic use, irrigation,

recreation etc

7. RESERVE SPECIFICAIONEcospecs (ecologicalcomponent of RQO)

Implementation methodsand operating rules for

Reserve

Monitoring protocolsMonitoring DSS, Baseline,Compliance monitoring

8. IMPLEMENTATIONDESIGN

IMPLEMENT &MONITOR

RQO

Provide resourceeconomic consequences

Cost/Confidenceanalysis

Projectscope

Reserve ComponentsRivers, Groundwater,Estuaries, Wetlands

1. INITIATE RDM STUDY- STUDY AREA- RDM LEVEL & COMPONENTS- STUDY TEAM

RDM protocols

RDM levelRapid I, II, IIIIntermediateComprehensive

?

2. DEFINE RESOURCE UNITS

System operation

Select IFR sites

Geomorphologicalzonation

Ecoregions

3. DEFINE ECOLOGICALCATEGORIES (EC) AND

RECOMMEND

EC ClassificationReference conditionsPresent Ecological StateTrajectories of changeEcological Importance and SensitivitySocio/Cultural ImportanceConstraints(EC specialist meeting)

Stakeholder ProcessCapacity buildingEmpowering

4. QUANTIFY ECOLOGICALWATER REQUIREMENT(EWR) SCENARIOS

Apply Process(BBM, Stressor Response, DRIFT)(IFR specialist meeting)

Data OrganisationCollate existing dataCollect additional infoAnalyse info

5. ECOLOGICALCONSEQUENCES OF

OPERATIONAL SCENARIOS(quantity & quality)

YIELD CONSEQUENCES OFRESERVE

Define operationalscenarios

CatchmentSystem Analysis

Integration BHN &Reserve

components

Yield & stakeholderrequirements,

operational constraints

Stakeholder processScenario implications &

assessment

6. DWAF MANAGEMENTCLASS DECISION MAKING

PROCESS

Information on categoriesother than Ecological, i.e.domestic use, irrigation,

recreation etc

7. RESERVE SPECIFICAIONEcospecs (ecologicalcomponent of RQO)

Implementation methodsand operating rules for

Reserve

Monitoring protocolsMonitoring DSS, Baseline,Compliance monitoring

8. IMPLEMENTATIONDESIGN

IMPLEMENT &MONITOR

RQO