Feasibility & Health Risk Assessment of Groundwater Recharge by TSE in the Kingdom of Bahrain

Transcription

1 The Arab Regional AGU Feasibility & Health Risk Assessment of Groundwater Recharge by TSE in the Kingdom of Bahrain Aqeel Ahmed, Waleed Al-Zubari, Alaa El-Sadek, and Mubarak A. Al-Noaimi WSTA 1 th Gulf Water Conference, Water in the GCC the Water-Energy-Food Nexus, Doha, April, 212

2 Overview Introduction Groundwater Resources in Bahrain and Groundwater Development Impacts Agriculture, Groundwater, and Tertiary TSE Feasibility of Groundwater Recharge by Tertiary TSE Methodology Results Conclusion and Recommendations

3 Introduction Groundwater (Dammam Aquifer) is the only natural water resource in Bahrain Part of an extensive regional aquifer (the Eastern Arabian aquifer), recharged by underflow GDC, 198

4 meters below sea level Dammam Formation Two Aquifer units (A & B zones) Cont., Introduction Adjacent to seawater on the east and brackish water (C zone) from the bottom A Bahrain main island Sitra island A' Geological Units A B C Neogene Formation + Recent deposits Alat Member Orange Marl Member Khobar Member 14 Sharks Tooth Shale M Limestone (Aquifer) A Rus Formation (+anhydrite & shales) 22 Shale and marl (Aquitard) A' Anhydrite (Aquitard) Underflow from Saudi Arabia aquifers Umm Er Radhuma Formation 32

5 Million cubic meters Cont., Introduction Significant increase in water demands in past four decades, met mainly by groundwater abstraction Total Water Requirements in Bahrain, industrial municipal agriculture

6 Million Cubic meters Heavy reliance on groundwater and unplanned utilization Prolonged over-exploitation Potentiometric level decline & Quality deterioration 3 Development of Dammam Aquifer in Bahrain Cont., Introduction 25 Water taken from GW Storage Safe Yield Wells Abstraction 5 Natural Springs Discharge

7 Cont., Introduction Potentiometric Levels Decline of the Dammam Aquifer in Bahrain Al-Shaikh Al-Safahiyah Al-Rahah Al-Qusaibi, 1997

8 Cont., Introduction Quality Deterioration of the Dammam Aquifer (Salinity) Salinity mg/l Historical salinity (1965)

9 Agriculture, Groundwater and TSE Agricultural Water Consumption, in Mm 3 (Groundwater &TSE) 2 15 Groundwater Tertiary TSE 1 5

10 Cont., Agriculture, Groundwater and TSE TSE Dynamics in Bahrain (Tubli Wastewater Treatment Plant) Inlet Tubli (Mm3/year) TSE Production (Mm3/year) TSE consumption (Mm3/year) Sea Overflow (Mm3/year) Partially treated or untreated

11 Drivers Rapid population growth High consumption patterns System Analysis of the Problem of Tubli Bay Pollution by Wastewater in Bahrain MAR? Cont., Agriculture, Groundwater and TSE Pressures 1 Increasing rates of municipal water consumption & Increasing rates of wastewater generation Pressures 2 Increasing inflow rates to Tubli treatment plant (centralized wastewater system & limited capacity) Response Increasing wastewater treatment capacity Decentralization Clean up Proposed tariff on Wastewater! Impacts State Increasing carryover rates and pollution Health, Environmental, Ecological, Aesthetics, Financial, economical, political, social losses

12 Feasibility of GW Recharge by TSE MAR using Tertiary TSE represents a promising and potential option in the management of water resources in the Kingdom of Bahrain (hydraulic benefits: water levels and salinity) However, associated health risks need to be assessed thoroughly (among other less concerns) before the implementation of such a scheme Objective: to evaluate the hydrogeological and environmental feasibility of recharging groundwater with surplus tertiary treated wastewater

13 Methodology Site selection by GIS and Criteria Matrix Cont., Feasibility of GW recharge Using geospatial data to select the best location for artificial recharge (geometry, transmissivity, quality of groundwater, water supply wells location, TSE distribution network and main reservoirs with possible surplus)/ GIS Simulation Modeling and Analysis of selected sites Develop a groundwater mathematical model for the surrounding areas of the selected sites; simulate artificial recharge using several scenarios, evaluate the hydraulic efficiency and benefits, and identify the most suitable site for MAR/ MODFLOW and MT3DMS simulation Health Risk Assessment Use simulation modeling to assess health risks of artificial recharge/ PMPATH and MT3DMS

14 Results Site selection by GIS & Criteria Matrix 1. Treated wastewater reservoirs tanks locations and capacity 2. Dammam Aquifer Transmissivity (T) 3. Domestic Water wells locations 4. Agricultural areas 5. Aquifer salinity 6. Treated wastewater emergency wells Two Selected Sites Malikya and Dumistan Cont., Adaptation Options ABUSAIBA MAQABA ADARI _2 _1 ABUSAIBA MAQABA ADARI _2 _1 JANABYHA JASRA ABUSAIBA MAQABA HAWARAT A'ALI A'ALI _2 _1 ADARI _2 _1 JANABYHA ABUSAIBA JASRA MAQABA HAMALA _1 BOURI _2 BUHAIR _1 _2 HAWARAT A'ALI A'ALI _2 _1 ADARI _2 _1 Hamad Town(Control JANABYHA Reservoir) DUMISTAN JASRA ABUSAIBA HAMALA _1 BOURI _2 BUHAIR _1 MAQABA _2 HAWARAT A'ALI A'ALI _2 _1 ADARI _2 _1 Hamad Town(Control JANABYHA Reservoir) ABUSAIBA DUMISTAN JASRA MAQABA HAMALA _1 BOURI _2 BUHAIR _1 _2 HAWARAT A'ALI A'ALI _2 _1 ADARI _2 _1 MALIKIYA Hamad Town(Control DUMISTAN JANABYHA Reservoir) HAMALA JASRA BOURI _2 _1 BUHAIR _1 _2 SADAD HAWARAT A'ALI A'ALI _2 _1 MALIKIYA Hamad Town(Control JANABYHA Reservoir) DUMISTAN JASRA HAMALA BOURI _2 _1 BUHAIR _1 _2 SADAD HAWARAT A'ALI A'ALI _2 _1 ZALLAQ MALIKIYA Hamad Town(Control Reservoir) DUMISTAN HAMALA BOURI _2 _1 BUHAIR _1 _2 ZALLAQ SADAD MALIKIYA Hamad Town(Control Reservoir) DUMISTAN SADAD ZALLAQ MALIKIYA ZALLAQ SADAD MALIKIYA SADAD ZALLAQ ZALLAQ Treated wastewater emergency wells Criteria Reservoirs Locations The 287 comparison aquifer salinity criteria Treated wastewater emergency wells Dammam Reservoirs Agricultura Outcrop Locations Areas Criteria Contour line (C.I=5) Rus Outcrop Dammam Domestic Reservoirs Water Outcrop Wells Locations Locations Criteria 286 Source: Water Resources Agricultural Directorate (28) areas Rus Outcrop Dammam Reservoirs Outcrop Locations 286 Salinity source: Water Resource Transmissivity Domestic Directorate.(26) 285 Water wells Criteria Rus Outcrop Dammam Reservoirs Outcrop Locations Source: 1 TSE AlShowaiey Contour Reservoirs 46 line (25) (C.I=1) Criteria Rus Outcrop Dammam Reservoirs Outcrop Locations Source: Swar (22) Rus Outcrop Dammam Outcrop Source: Water Resource Directorate.(28) Rus Outcrop Source: Ministry of Works

15 million cubic meters Cont., Results Cont., Adaptation Options Simulation modeling and analysis of the two selected sites Abstraction wells Proposed injection locations Constant head 8 7 Actual Years Prediction Years TSE Production TSE Consumption TSE Surplus Max Production Water levels Year Salinity

16 Cont., Feasibility of GW recharge Cont., Results Six scenarios are developed National strategic water storage plan scenario: [2, m 3 /day average daily consumption] / 2 = 77 Mm 3 (38.5 Mm 3 per location) Surpluses storage Scenario: 7 Mm 3 /year = 35 Mm 3 (17.5 Mm 3 per well) Inject all the quantities from scenario 1 (77 Mm 3 ) in one well only: (3a: Dumistan, 3b: Malikiya) Inject all the quantities from scenario 2 (35 Mm 3 ) in one well only: (4a: Dumistan, 4b: Malikiya).

17 Water Level (m) Water Level (m) Water Level (m) Water Level (m) Water Level (m) Water Level (m) Water Level (m) Water Level (m) Water Level (m) Cont., Results Cont., Feasibility of GW recharge Simulation modeling and analysis of selected sites (water levels) Malikiya Water Level A Observation Well 2 Hamala Water Level 1 Sadad Water Level Dumistan Water Level Zallaq Water Level Observation 1 Water Level Time (day) -8 Observation 2 Water Level Without 18 Recharge With Recharge 72(scenario 9 1) 18 With Recharge 126 (scenario 2) With Recharge 18 (scenario 3a)Dumistan With Recharge (scenario 4a) Dumistan With Recharge (scenario 3b) M alikiya" With Recharge (scenario 4b) M alikiya Observation Water 54Level 72 9 Time 18 (day) Time (day) Without Recharge With Recharge (scenario 1) With Recharge (scenario 2) With Recharge (scenario 3a)Dumistan With Recharge (scenario 4a) Dumistan With Recharge (scenario 3b) Malikiya With Recharge (scenario 4b) Malikiya Observation 4 Water Level Without Recharge With Recharge (scenario 1) With Recharge (scenario 2) With Recharge (scenario 3a)Dumistan With Recharge 36 (scenario 4a) Dumistan With Recharge (scenario 93b) Malikiya With Recharge (scenario 144 4b) Malikiya Time (day) Without Recharge With Recharge (scenario 1) With Recharge (scenario 2) With Recharge (scenario 3a)Dumistan -2-5 Time (day) -2 With Recharge (scenario 4a) Dumistan With Recharge (scenario 3b) Malikiya With Recharge (scenario 4b) Malikiya Without Recharge With Recharge (scenario 1) With Recharge (scenario 2) With Recharge (scenario 3a)Dumistan -3 With Recharge (scenario 4a) Dumistan With Recharge (scenario 3b) Malikiya With Recharge (scenario 4b) Malikiya Time (day) Without Recharge With Recharge (scenario 1) With Recharge (scenario 2) With Recharge (scenario 3a)Dumistan -7 Time (day) With Recharge (scenario 4a) Dumistan With Recharge (scenario 3b) Malikiya With Recharge (scenario 4b) Malikiya -5-8 Without Recharge With Recharge (scenario 1) With Recharge (scenario 2) With Recharge (scenario 3a)Dumistan With Recharge (scenario 4a) Dumistan With Recharge (scenario 3b) Malikiya With Recharge (scenario 4b) Malikiya -9 Time (day) Without Recharge With Recharge (scenario 1) With Recharge (scenario 2) With Recharge (scenario 3a)Dumistan With Recharge (scenario 4a) Dumistan With Recharge (scenario 3b) Malikiya With Recharge (scenario 4b) Malikiya Time (day) Without Recharge With Recharge (scenario 1) With Recharge (scenario 2) With Recharge (scenario 3a)Dumistan With Recharge (scenario 4a) Dumistan With Recharge (scenario 3b) Malikiya With Recharge (scenario 4b) Malikiya

18 Cont., Results Cont., Feasibility of GW recharge Simulation modeling and analysis of selected sites (Salinity) scenario 1 scenario 2 scenario 3a (Dumistan) scenario 3b (Malikiya) scenario 4a (Dumistan) scenario 4b (Malikiya)

19 Cont., Results Cont., Feasibility of GW recharge Health Risk Assessment (Pathogens) using PMPATH scenario 1 scenario 2 scenario 3a (Dumistan) Hamala dometic wellfield Hamala dometic wellfield Hamala dometic wellfield Farrmers wells Farrmers wells Farrmers wells scenario 3b (Malikiya) scenario 4a (Dumistan) scenario 4b (Malikiya) Hamala dometic wellfield Hamala dometic wellfield Hamala dometic wellfield Farrmers wells Farrmers wells Farrmers wells

20 Cont., Results Cont., Feasibility of GW recharge Health Risk Assessment (Nitrates) Using MT3DMS (S 3b)

21 Concentration (mg/l) Concentration (mg/l) Concentration (mg/l) Cont., Results Health Risk Assessment (Nitrates) Cont., Feasibility of GW recharge North of Malikiya Distance from Malikiya Location (m) West of Malikiya 5 Year Simulation of scenario 3b (about 4 Km) Distance from Malikiya Location (m) South of Malikiya Distance from Malikiya Location (m)

22 Conclusion and Recommendations Groundwater artificial recharge/storage enhancement using surplus tertiary TSE is a viable option for Bahrain at a certain location in western Bahrain, where maximum hydraulic benefits and minimum health risks can be achieved Field pilot study for artificial recharge using tertiary TSE at the selected location to further evaluate the feasibility of artificial recharge and validate the modeling results is a pre-requisite for such plans MAR should be looked at as a major component of national water resources management and planning in Bahrain To develop a 3D simulation model for Bahrain aquifer system (including C zone), that can be used in the management of groundwater, including the evaluation of artificial recharge

23 THANK YOU!