Physical & Quality Groundwater Monitoring Information for effective management

1. Physical & Quality Groundwater Monitoring Information for effective management Groundwater Management for Hygiene and Sanitation IWSD – Harare June 2011

2. GROUNDWATER STATUS QUO • Millions of m3 pumped every year: Monitored? Who? How? • 100’s of thousands of users: Registered? Controlled? • 10’s of thousands of wells/boreholes: Registered? Maintained? Info. about location, abstraction levels, water levels, water quality, formation, etc – • 1000’s of sources of pollution: Location, nature & quantity of pollutants? aquifer vulnerability? • Many governing departments/institutions: Joint management ? Coordination / cooperation?

3. MONITORING: WHO? • Who requires/requests for monitoring? • Who determines priorities and expected outcomes? • Who pays? • Who implements the monitoring? • Who owns/ shares the data?

4. GROUNDWATER USE AND QUALITY MONITORING • Principles of groundwater monitoring • Monitoring cycle and tools • Monitoring resource use and aquifer response • Groundwater quality monitoring • Effectiveness, cost and quality control • Examples

5. WHAT IS MONITORING NOT? PROVIDING IRRELEVANT INFORMATION TO ILL DEFINED QUESTIONS

6. WHAT IS GROUNDWATER MONITORING? Groundwater monitoring comprises the collection, analysis and storage of data on a regular basis to provide information for effective groundwater management to a variety of stakeholders. Monitoring makes groundwater visible, if…….

7. Groundwater Monitoring Systems by Function

8. Purpose and function of monitoring Pollution source Impact monitoring Object of protection Early warning Impacts Risks Risks Impacts Trend monitoring Groundwater abstraction Compliance /management + early warning monitoring

9. Groundwater is invisible

10. RECHARGE ESTIMATES MAPUTO Maputo 1984 Recharge estimations So = 40 mm Rainfall: 800-850 mm/year Recharge: 165-185 mm/year

11. MONITORING: DIFFERENT PURPOSE <> SAME DATA

12. WHY IS GROUNDWATER MONITORING IMPORTANT? Groundwater is a hidden resource to which we have no direct access Contrary to surface water, changes in groundwater quality and quantity are slow processes which cannot be determined by snap shot monitoring Changes in groundwater quality are often irreversible

13. GROUNDWATER USE AND QUALITY MONITORING Principles of groundwater monitoring Monitoring cycle Monitoring resource use and aquifer response Groundwater quality monitoring Effectiveness, cost and quality control Examples

14. THE MONITORING CYCLE Trends and changes Impacts and risks Compliance Management question and monitoring objectives Definition of information needs Groundwater specific Water use Supporting data Collection of static and dynamic data Data storage, interpretation and dissemination Management information and actions Information > data > information

15. WHAT DATA DO WE COLLECT?

16. HOW DO WE MONITOR ? • Monitoring networks • Network density (hydrogeological and hydro-chemical heterogeneity/complexity) • Location observation points (existing used wells, abandoned wells, new observation wells, climate, surface water, water use) • Monitoring parameters • Measuring and sampling frequency (instruments, budget, monitoring program) • Satellite images and airborne surveys • Statistics Factors determining design • Budget, • Monitoring objectives

17. MONITORING POINTS Groundwater Wadi Flows Water use Climate River water

18. GROUNDWATER USE AND QUALITY MONITORING Principles of groundwater monitoring Monitoring cycle and tools Monitoring resource use and aquifer response Groundwater quality monitoring Effectiveness, cost and quality control Examples

19. AQUIFER REPONSE: WATER LEVELS Example: Water saving to reduce aquifer depletion • Historic data • Baseline data (reference) • Monitoring data

20. MONITORING FOR RESOURCE USE & AQUIFER RESPONSE Monitoring of groundwater levels and groundwater use is needed to verify the predicted aquifer response for management scenarios. Important issues: • knowledge of the reference situation: historic and baseline data • groundwater flow is related to the groundwater levels • water level response is related to the use But: There remains always a certain uncertainty

21. HYDROGRAPHS: NYAMANDLOVU SST AQUIFER

22. MONITORING GROUNDWATER USE • Direct monitoring - metering and regular inspection • Indirect monitoring • energy consumption and average pumping rates • pumping hours and average pumping rate - population estimates and random tests (drinking water) - use of remote sensing information (irrigation water use)

23. GROUNDWATER USE AND QUALITY MONITORING Principles of groundwater monitoring Monitoring cycle and Monitoring resource use and aquifer response Groundwater quality monitoring Effectiveness, cost and quality control Examples

24. MONITORING FOR GROUNDWATER QUALITY Sampling of production wells • cheap but often unreliable/not representative • useful to determine the reference situation Sampling of purpose- drilled monitoring wells: • Reference monitoring for natural water quality /natural recharge • Offensive monitoring of pollution sources • Defensive monitoring for groundwater supplies • Evaluation monitoring for sites of known aquifer contamination

25. MONITORING STRATEGIES Offensive monitoring Early detection of incipient aquifer contamination by known pollution sources Defensive monitoring Provide warning of pollution plumes threatening potable well fields or individual wells

26. WHERE TO LOCATE MONITORING POINTS ?

27. MONITORING FOR GROUNDWATER QUALITY Physical parameters (indicators) • Electric conductivity /temperature • pH • DO • Manuel and automatic recorders Water sampling and analysis parameters selected in the light of the quality objective and pollution hazard assessment: quality assurance and control

28. GROUNDWATER USE AND QUALITY MONITORING Principles of groundwater monitoring Monitoring cycle and Monitoring resource use and aquifer response Groundwater quality monitoring Effectiveness, cost and quality control Examples

29. HOW ARE RESPONSIBILITIES SHARED ? Legal and regulatory basis required through water rights / water allocation plan /permitting system etc Typical division of responsibilities • National level: basic reference networks/ climate stations • Regional level/RBA/AMOR: regulation control + protection • Contractors: contractual obligation for well testing • Large abstractors: monitoring requirements in permit • Local water users: self monitoring / awareness + Data collected by other agencies

30. QUALITY ASSURANCE AND QUALITY CONTROL Prevention (assurance) is better than cure (control) • Starts with the observer: cross checks, keep your eyes open • Guidelines: follow procedures (e.g. for sampling) • Keep copy of field readings • QA/AC on chemical analysis • QC procedures for data entry in MIS • QC control in data processing

31. HOW ENSURE THAT MONITORING IS COST EFFECTIVE? Monitoring is considered expensive because the return on investment is generally not visible in the short run • Monitoring by objectives • Include cost-benefit analysis in project design • Promote cost effectiveness and reliability by: • Defining clear information needs • Use of data already collected in other programs • Use of existing wells (abstraction wells and abandoned wells) • Use of indicators: water level/temperature /EC (divers) • Promoting self monitoring and self regulation • Effective QC and QA system

32. GROUNDWATER USE AND QUALITY MONITORING Principles of groundwater monitoring Monitoring cycle and Monitoring resource use and aquifer response Groundwater quality monitoring Effectiveness, cost and quality control Examples

33. BANGKOK: REGULATION AND GROUNDWATER FUND • Regulatory and economic measures • Imposed based on monitoring information Tariff 8.5 Bht Tariff 3.5 Bht Groundwater fund used for: • Monitoring • Research • Training & manpower dev.

34. CONCLUSION Monitoring makes groundwater visible if it: • addresses well-defined management information needs (demand driven), is • cost-effectively implemented providing • reliable information WHAT IS THE HEIGHT OF THAT TOWER IN METERS ? I HAVE MEASURED IT WITH TWO DIFFERENT MEASURING TAPES AND THE HEIGHT IS 26 +/- 2 METERS. Thank you

35. Exercise: 3 Groups 1 Monitoring a dune infiltration system to protect a drinking water well field against seawater intrusion 2 Monitoring plan for an industrial site to prevent spreading of possible contaminants through the groundwater 3 Monitoring system for trend monitoring in a sedimentary shallow aquifer in river basin

36. Exercise: 3 Groups • Define the monitoring objectives and basic design parameters • What are the main benefits and who are the main beneficiaries of the monitoring • Suggestions to make the monitoring plan cost effective • How to assure sustainable financing? • Who will implement the monitoring and how is the monitoring information handled to address the management objectives

37. HYDROCHEMISTRY: QA and QR !!! Field measurements (EC and pH) Sampling procedures Ion balance Extreme values (high and low) Use certified labs Contra expertise (5% of the samples)

38. GROUNDWATER SAMPLING