Groundwater Resources Sustainability Indicators marzo...Total abstraction GW x100% Exploitable GW resources Exploitable GW resources - amount of water that can be annually abstracted

Groundwater Resources Sustainability Indicators

Working GroupUNESCO/IAEA/IAH/IGRAC

J. Vrba (Chairman), R.Hirata, J.Girman,N.Haie, A.Lipponen,

E.Lopez–Gun,B.Neupane, T.Shah, B.Wallin

IHP VI Project: Groundwater ResourcesSustainability Indicators

Theme 1:Global Changes and Water Resources+Focal Area 1.1: Global Distribution of Resources: Water Supply and Water QualityObjective: To develop improved techniques, indicators and data bases for integrated global water resources assessmentProject implementation: UNESCO / IAEA / IAH Working Group, from 2002 to 2006WWAP: Indicator-based Assessment of the State of the World‘s Water Resources

Groundwater indicators development

Simple indicators have been chosen to begin the process basedon sound scientific understandingProposed groundwater indicators are based on measurable data, provide information about the present status and trends in groundwater quantity and quality and are focused on social, economic and environmental attributes of groundwater resources planning, policy and management Groundwater indicators are based on a single data (variable) or an output value from a set of data (aggregation of variables). Some indicators are aggrgated into an index often acrrosdifferent measurement units and they results are dimensionless. Weighting and rating methods are applied to index construction.

GW indicators are based on Cause-Effect approach

DPSIR framework

Driving force indicator – shows the motivation of water use (agricultural development)Pressure indicator – human activities exert pressure on water (N-load on farms)State indicator – pressure causes a quality/quantity change in the state of water (nitrate in groundwater)Impact indicator – describes the effects of the pressure (nitrate in drinking water) Response indicator – social response to the changes, which are reflected in environmental policy (control of fertiliser use and manure production).

5toicdasiigws

Proposed indicatorsDependence on groundwater

Indicator Characteristics

Renewable groundwater resources / Inhabitants(m3/y/in)Evaluation of renewable GW resources is based on recharge+inflow + seepage- discharge -baseflow -outflow

Estimate the total amount of ground water for many uses that exist in the country. This is adriving force indicator of great significance to the planners, policy and decision makers and social and economic relevance.Indicator supports IWRM

Groundwater as a percentage of total use of drinking water on the country levelData are available in many countries, because use of drinking water is usually based on licences and is registered by water companies

It expresses how important is groundwater for drinking water supply in the country and reflectsthe social and economic conditions of the society, accessibility to water resources, and economic value of water

Share of groundwater in public water rupplies (%) exluding

Russian Federatin

Proposed indicatorsDependence on groundwater

Indicator Characteristics

Number of farmer dependenton GW for agricultural activities / Total population of the countryComplementary indicators:Population of the country / Number of people engaged in farming and stock rearing

Proposed indicator is designated to signify the importance of groundwater in the rural livelihood and household incomesIn the developing worth, the poor people have come to depend on groundwater use in far larger numbers than reservoir- based large surface water systems

Dependency of agricultural population on groundwater (%)

Proposed indicatorsGroundwater exploitation

Indicator CharacteristicsTotal GW abstraction x 100%GW rechargeTotal GW abstraction means total withdraw of water from a given GW body by wells, springs and other ways for the purpose of water supply and other usages. Indicator is calculated as a sum of licenced and unlicenced GW abstraction and GW natural discharge.Natural and induced recharge was applied for indicator construction

Excessive abstraction of GW without the understanding of recharge rates can cause problems, particularly depletion of the resourceThree scenarios are proposed: groundwater abstraction less than90% of recharge,groundwater abstraction = recharge, Groundwater abstraction more than 100% of recharge

Total abstraction GW x100%Exploitable GW resourcesExploitable GW resources - amount of water that can be annually abstracted under current socio-economic constrains and ecological conditions.

Three scenarios are proposed:groundwater abstraction less the 90% of exploitable amount, groundwater abstraction = exploitable amount, groundwater abstraction more than 100% of exploitable amount

Total groundwater abstraction as percentage of average groundwater recharge

Proposed indicatorsGroundwater exploitation

Indicator Characteristics

Total non renewable GW resources / Annual abstraction of non renewable GW resourcesNubian aquifer:exploitable groundwater reserves 6 500 km/3, current extraction /a 1,6 km/3, aquifer lifetime 4 062 year

Non-renewable groundwater - mean annual aquifer renewal is less than0,1% of the aquifer storage (average renewal period would be at least 1 000 years). The total calculated lifetime of the non-renewable aquifer should be calculated as a mean value of groundwater abstraction over a significant range of years

Groundwater depletionΣ area with GW depletion problemTotal area of studied aquifer

Declines in hydraulic head, associated to other issues (change of base flow, lost of springs, change of groundwater quality, origin and/or age, land subsidence) can reflect problems of groundwater depletion

Total exploitable non-renewable groundwater resources (m/3) –Annual

abstraction of non-renewable groundwater resources (m/3)

Proposed indicatorsGroundwater quality and vulnerabity

Indicator Characteristics

Groundwater vulnerability

Four classes of vulnerability are proposed:High, Moderate, Low, Negligible

GW vulnerability is a intrinsic property of a groundwater system that depends on the ability of that system to cope with human and natural impacts. Vulnerability variables: recharge, soil, unsaturated zone lithology and thickness, aquifermedia and hydraulic conductivity

Groundwater qualityΣarea GW natural quality problemTotal area of studied aquiferΣarea increase concentr of SVTotal area of studied aquiferSV: chloride, nitrate, and EC

Indicator informs about the present status and trends in groundwater quality. For anthropogenic problems, the indicator is restricted to diffuse sources (sanitation and agricultural practices)

Proposed indicatorsGroundwater quality and vulnerability

Indicator Characteristics

Groundwater treatment requirementsThree categories are proposed: Apt for use without treatment, Simple treatment (aeration, filtration,removal of iron by separation),Technologically demanding treatment (coagulation, floculation, biological methods, membrane methods., de-salinization)

This indicator describes whether groundwater can feasibly be made potable or usable for other purposes without or with treatment (e.g.drinking water, irrigation water, cooling water)

Case studies

Groundwater indicator case studies: Spain (Aquifer level - Sierra de Estepa, Sevilla)Nubian Aquifer (Transboundary aquifer level) Republic of South Africa (National level)Finland (National level)Brazil (São Paulo State level)

Conclusions

Indicators development is still in infancy We are only beginning to talk about indicator based resource planning, management and policy makingTo undrestand the interrelationships between different indicators need much more reflection, study, consultation and dataIntegrated approach to the generation of more complex groundwater indicators and their aggregation into water related indexes,which condensate wide range of information, is theurgent task for the near futureStep by step development of groundwater monitoring networks and programmes with the scope to fill up the gap of groundwaterdata has to be subsidized and implemented within national and international water policy and management plans

Conclusions

Participatory approach in indicators development based onobjectives and interests of different target groups and mode of communication between indicator developers and indicator users is important element in the process of grounwater resources sustainable indicators generation and implementationThe aim of this process is to improve groundwater resources assessment and sustainable management, to achieve social,economic and environmental benefits for the society and to support governance policy based on coordination of water actions between different territorial levels – local, national, regional,global