1. P R O V I D I N G E N G I N E E R E D S O L U T I O N S
June 1, 2015

2. ACTION INTERNATIONAL SERVICES
CORE SERVICES
 Groundwater Control (Dewatering) & Hydrogeological Investigation
 Industrial Services & Equipment Rentals
Saudi Arabia
United Arab Emirate
Qatar
OmanBahrain

3. DEWATERING CHALLENGES IN QATAR
1. High variation of Qatar geology & Hydraulics
2. Long procedure for permit
3. Lack of discharge facilities
4. Groundwater treatment & management

4. OVERVIEW OF QATAR GEOLOGY

5. QATAR GEOLOGY - AMC
Level(m,QNHD)
Reference: AMC-QDVC

6. HIGH VARIATION IN GEOLOGY/HYDRAULIC – AMC AS CASE STUDY
150m
Section Section A Section B
Excavation level
(m QNHD)
-20.675 -11.485
Horizontal Hydraulic conductivity
conductivity (m/s)
1.03E-4 4.61E-5
Flow (m3/h) 103 35

7. PRESENT & PROSPECTIVE GROUND INVESTIGATION
 Centered around Foundation with little or no dewatering consideration
Present Ground Investigation
Prospective Ground Investigation
1. Detailed Hydraulic test (vertical & horizontal Hydraulic conductivity)
2. Groundwater physical & chemical analysis
3. Geophysical test

8. APPROACH TO DEWATERING CHALLENGES
 Detailed Subsurface & Hydraulic Assessment
1. Historical Information & Site Experience
2. Review of soil investigation report
3. Analytical modelling based on 1 & 2
4. Numerical modelling (2D/3D) based on 1 & 2
5. Insitu Test (Pumping Test & Slug Test)
6. Recalibration of 3 & 4 based on 5.

9. APPROACH TO DEWATERING CHALLENGES
Step 1:
Visual Investigation/ Site
visit
Historical Data/Dewatering
Experience within location
Soil Investigation
Report
Numerical (2D/3D) &
Analytical Model
Step 2:
Pumping Test
Slug Test
Insitu Test
Model
recalibration

10. 3D MODEL FOR A METRO STATION IN QATAR

11. ADVANTAGES OF HYDRAULIC TEST – PUMPING TEST
I. Estimate hydraulic parameters (vertical & horizontal hydraulic conductivity) which
are important in designing cost effective dewatering system
II. It gives a wide range of aquifer properties on like Slug test and Percolation test
which are location specific.
III. It gives good estimate of expected flow, pump requirement for dewatering works
IV. It gives a better understanding of hydraulic behavior over a period of time
V. Analyses is more detailed with little uncertainty compared to other hydraulic test

12. GROUNDWATER MANAGEMENT PRACTICES
Sources of Water in Qatar
1. Desalination – 48%
2. Fresh water from Aquifer– 38%
3. Sewage water – 14%
Qatar is the second most water stressed in the world – Water stress index 2011
Conservation Practices
1. Onsite treatment & Reuse
2. Onsite treatment & Discharge to sewer system
3. Groundwater recharge practices
4. Optimized groundwater design for dewatering by performing relevant
hydraulic test
I. Sewer size due to discharge volume
II. Permit
III. Expected Treatment limit prior to discharge

13. GROUNDWATER DISCHARGE MANAGEMENT
1. Onsite treatment & Reuse
2. Onsite treatment & Discharge to sewer system
3. Groundwater recharge practices
4. Optimized groundwater design for dewatering by performing relevant hydraulic test
I. Sewer size due to discharge volume
II. Permit
III. Expected Treatment limit prior to discharge

14. WHERE WE CREATE VALUES
1. Project engagement
2. Understanding work program
3. Interpreting soil investigation report & geotechnical information for dewatering
design
4. Recommendation of relevant Insitu hydraulic test based on project
5. Dedicated team – Project Engineers & Hydrogeologist
6. Shared understanding of critical part & Risk
I. Soil contamination
II. Water quality & Required treatment
III. Potential cavities/sinkholes
IV. Excavation type– Open or Shored
V. Flow Estimate & Discharge options
Tender Stage

15. WHERE WE CREATE VALUES
Sub. Contractor Tender
1. Understanding work program
2. Recalibration of design/models and assumptions during the tender stage
3. Optimizing system to accommodate budget
Project Execution
1. Adherence to standard practise
2. Daily system monitoring (Automated & Manual) and performance reporting against
I. Lateral pressure (open excavation/shored system)
II. Uplift pressure
3. Dedicated Project & Site Engineers

16. WHERE WE CREATE VALUES
Tender Stage
Sub. Contractor Award
Contract Award
Sub. Contract Tender
Project Execution
1. Team continuity
2. Better program understanding
3. Good project management
Benefits

17. Thank You