linking groundwater flow and transport models, gis technology, satellite images and uncertainty...

05/02/2023Elfeki, Ewea, & Al-Amri -ICWRAE 2010

LINKING GROUNDWATER FLOW AND TRANSPORT MODELS, GIS TECHNOLOGY, SATELLITE IMAGES AND UNCERTAINTY QUANTIFICATION FOR DECISION MAKING:

BURAIMAN LAKE CASE STUDY, JEDDAH, SAUDI ARABIA

Amro Elfeki, Hatem Ewea, and Nassir Al-Amri

Dept. of Hydrology and Water Resources Management ,Faculty of Meteorology, Environment & Arid Land Agriculture, King

Abdulaziz University , P.O. Box 80208 Jeddah 21589 Saudi Arabia


OUTLINE Objective of the Research Site Map and Data Acquisition Methodology Results Conclusions Outlook


OBJECTIVES OF THE RESEARCH Developing a methodology for linking

flow and transport models, satellite images, GIS technology and uncertainty quantification for decision making.

Case Study: Prediction of the fate of the sewage plume released form Buraiman lake, Jeddah, KSA


METHODOLOGY The methodology is an integration of

Flow and Transport Models.

Satellite Images.

GIS Technology.

Uncertainty Quantification (Monte-Carlo Method). For providing a risk map for decision making

. 0h

C C Ct

v Dx x x

k

2

Uncertainty in Conceptual Models. 0

. 0

Uncertainty in hydraulic conductivity, k

h

h

k

k

GISMonte-Carlo

Method


CLASSIFICATION OF UNCERTAINTYConceptual Model Uncertainty: Darcy’s and Fick’s Laws. Confined versus Unconfined aquifers

Geological Uncertainty: Connectivity and disconnectivity of the layers, geological sequence, boundaries between geological units.

Parameter Uncertainty: Hydraulic Conductivity porosity.

Hydro-geological Uncertainty: Constant head boundaries, impermeable boundaries, Plume boundaries, source area boundaries.

0 50 100 150 200 250Horizontal Distance between W ells (m )

-50

0

Dept

h (m

)

W ell 1 Well 2

? K(x,y,z)?

(x,y,z)?

C(x,y,z)?H=?

H=?

?

???

? ?

?

?

?


SEWAGE LAKE: GENERAL LOCATION

A B

Satellite Images

Buraiman Lake (Musk Lake) located in the east of Jeddah highway.

Location: ~25 Km to the east of Red Sea coast.

~ 50,000 m3 /day are discharged into the lake.

Volume is more than 10 million m3

No outflow.Mohorjy and Khan(2006) Preliminary Assessment of Water Quality along the Red Sea Coast near Jeddah, Saudi Arabia, Water International, vol 31(1), pp 109-115 Basamed (2002). Hydrochemecal study and bacteriological effect on groundwater in the northern part of Jeddah district, MSc. Faculty of Earth Sciences, kau.


BURAIMAN LAKE (SITE VISIT)


CONCEPTUAL MODEL•The contaminant source starts from the dam lake.•The shape is approximated by a rectangle. •The leachate and ambient groundwater are connected.


DIRECTION OF GROUNDWATER FLOW AND GWL

About 20 degrees with the Horizontal

Al-Sefry and Sen (2006) Groundwater Rise Problem and Risk Evaluation in Major Cities of Arid Lands—Jeddah Case in KSA, Water Resou. Management 20:91-108


SEWAGE WATER DATA

Liptak, B. G. , (1974), Environmental Engineers’ hand book: Vol.1: Water pollution. Chilton book company, Radnor, Pennsylvania.

Wastewater Constituents 0 SOLIDS 0 SUSPENDED

125DISOLVED

150 DBOD 60 NITROGEN

100CHLORIDS

100 ALKALINITY SUM 535 MG/L 0.535 G/L M3=1000L 535 G/M3 0.535 KG/M3 TRUCK 20 TON 20 M3MASS OF WASTE= 10.7

KG/TRUCK

# TRUKS/DAY 800 8560 KG/DAY 3.124E+09 G/YEAR 2.57E+08 g/month 3124400 kg/year


1-D GW SURFACE PROFILES

1 21

h hh h x

L

2 2

1 221

h hh h x

L


ANALYTICAL SOLUTION OF TRAVEL TIME (CONFINED AQUIFER)

1 21

1 2

1 2

0 1 2

L

h hh h x

Lh hdhq K K

dx Lh hq Kv

n n Ldx dxv dtdt v

dxth hK

n L

2

1 2

nLtK h h


ANALYTICAL SOLUTION OF TRAVEL TIME (UNCONFINED AQUIFER)

2 21 22

1

2 21 2

2 21 22

1

2 21 2

2 21 22

1

2 21 22

12 201 2

2

2

2 L

h hh h x

Lh h

dh Lq K Kdx h h

h xL

h hq K Lvn n h h

h xL

dx dxv dtdt v

h hnt h x dxLh h

KL

3

2 21 2 2

1

32 2

1 22 31 12

2 21 2

2 ( )3

,

4

3

ax bax bdx

ah h

a b hL

h hnt h hLh h

KL


TRAVEL TIME FOR CONFINED AND UNCONFINED AQUIFERS

t = 37 years

t = 49 years

2

1 2

nLtK h h

3

2 21 22 3

1 122 2

1 2

4

3

h hnt h hLh h

KL

R = 0m/dayk = 120m/dayL = 21800mh1 = 73mh2 = 0m n 0.25-


GROUNDWATER LEVELS


VARIABILITY IN HYDRAULIC CONDUCTIVITY

120 /302 /

500

( )

Log-

k

K m daym daym

ss Exp

K Normal Distribution

Alquhtani, M.B. and W.M. Shehata, 2003, Vulnerability map of the groundwater rise in Jeddah, Saudi Arabia: 12th Asian regional conf. on soil mechanics and geotechnical engineering, 4-8 August, 2003, Singapore, chapter 3-3, pp 357,

Estimated Parameters


2-D GROUNDWATER MODELS

Un-Confined Aquifer

0h hK Kx x y y

2 2

0h hK Kx x y y

Confined Aquifer


GWL CONTOUR OF A SINGLE REALIZATION


TRANSPORT MODEL Governing equation of solute transport :

C is concentration Vx and Vy are pore velocities, and Dxx , Dyy , Dxy , Dyx are pore-scale dispersion coefficients

x y xx xy yx yyC C C C C C CV V D D D Dt x y x x y y x y

* - i jmij ijL L TVV

D V DV

*mDij

L

T

is effective molecular diffusion,

is delta function,is longitudinal dispersivity, andis lateral dispersivity.


RANDOM WALK METHOD 1 22 2xy yxx xp p x L T

D VD VX t t X t V t Z V t Z V tx y V V

1 22 2yx yy y xp p y L T

D D V VY t t Y t V t Z V t Z V tx y V V

The displacement is a normally distributed random variable, whose mean is the advective movement and whose deviation from the mean is the dispersive movement.

EFFECTIVE POROSITY 0.3 LONGITUDINAL DISPERSIVITY 2m TRANSVERSE DISPRSIVITY 1m ∆x 100m ∆y 100m LENGTH OF AQUIFER 21800m DEPTH OF AQUIFER 20m SOURCE DIMENSIONS 100x100 m ∆t 30.14days INJECTED MASS 2.57E+08grams/monthNUMBER OF PARTICLES 1000


PLUMES ENVELOPE AND SINGLE PLUME

Confined

Un-Confined


SINGLE PLUME AND ENSEMBLE PLUMES (C/U)ConfinedUn-

Confined

t = 37 yearst = 49 years


CONCLUSIONS GW and transport models can be connected with GIS

and satellite images to visualize the flow pattern and pollution transport.

The Monte-Carlo methodology together with GIS and satellite images are useful tools to account for uncertainty and providing maps of uncertainty (Envelop).

Well data showed quasi linear aquifer response when compared with quadratic aquifer response. A point that needs in depth investigation in arid zones.


OUTLOOK Perform elaborated study with more

reliable data. Validation of the results by collecting

samples from locations indentified by this study and check for the level of pollution.

Check the validity of the aquifer response in arid zones (linear versus quadratic response).

linking groundwater flow and transport models, gis technology, satellite images and uncertainty...

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