Upload
barry-bradford
View
223
Download
0
Tags:
Embed Size (px)
Citation preview
Groundwater ModelingGroundwater ModelingStudy case : Study case : Central Plain of ThailandCentral Plain of Thailand
Werapol BejranondaDepartment of Geohydraulics and Engineering Hydrology
University of Kassel, Germany
December 16, 2009December 16, 2009
ContentsContentsStudy Area / Groundwater hydro.Study Area / Groundwater hydro.
MethodologyMethodology
Groundwater ModelingGroundwater Modeling
Application of the modelApplication of the model
Study AreaStudy Area
GW BasinsGW Basins
Upper Central GW Basinof great central basin
•Agricultural
*The first upper centralregional GW Model
Lower Central GW Basinof great central basin
•Industrial•Agricultural
Bangkok(Capital)
Hydrogeological map ofupper central GW basin
Geological Map of Thailand
Study AreaStudy AreaStudy Area Boundary
Surface WaterSurface Water
4 Main Streams-Yom Rive-Nan River-Ping River-Sakaekrang River
cover 5 main surface-water basins
N
EW
S
žºØÃÕ
µÒ¡
àÅÂ
ªÑÂÀÙÁÔ
ÅÓ»Ò§
¹¤ÃÃÒªÊÕÁÒ
á¾Ãè
ºØÃÕÃÑÁÂì
ÍØÃÒ¹Õ
ྪúÙóì
¢Í¹á¡è¹
¾ÔɳØâÅ¡
áÁèÎèͧÊ͹
žºØÃÕ
ÊØ⢷ÑÂ
ÍصÃÔµ¶ì
¹¤ÃÊÇÃäì
ÍØ·ÑÂÒ¹Õ
ÅÓ¾Ù¹
¡ÓᾧྪþÔÔµÃ
ªÑ¹ҷ
˹ͧºÑÇÅÓÀÙ
ÍèÒ§·Í§ÊÔ§ËìºØÃÕ
50 0 50 100 150 200 Kilometers
400000
400000
450000
450000
500000
500000
550000
550000
600000
600000
650000
650000
700000
700000
750000
750000
800000
800000
850000
850000
900000
900000
1700000 1700000
1750000 1750000
1800000 1800000
1850000 1850000
1900000 1900000
1950000 1950000
2000000 2000000
¢Íºà¢µÑ§ËÇѢͧâ¤Ã§¡ÒÃ
Study AreaStudy Area
Project study area covers 6 Provinces
47,000 km2
KPP
SKT
UTD
PSL
PCT
NKS
Existing Conjunctive UseExisting Conjunctive Use•Irrigation areaIrrigation area•Rainfed areaRainfed area•Personal GW pumpsPersonal GW pumps
Study flowchart
Math-Model Design
Review Conjunctive Use in study area
Conceptual Groundwater Model
Calibration and Verification
Modeling Result
GW Use Pattern Analyze
Space Dimension- Irrigation Area- Surface Basins- Aquifer Types
Time Dimension- Water Situations- Seasons
Groundwater Uses
Surface Water Balance Analysis Result
Surface Water Uses
Surface Water Shortage
Industrial/Private Use
Agricultural Use
Domestic Use
Questionnaires
- Groundwater Levels- Hydraulics Properties- Recharge
Field Investigationand
Literature Review
Applications
GW use ??GW use ??Field data collectionField data collection ( (pumping behaviorpumping behavior))
area crops/year season pumping/crop day/pumping hours/day
irrigation 2.5dry 6.0 2.6 19.3
wet 3.8 2.3 19.3
rainfed 2.0dry 6.5 3.1 22.0
wet 3.1 2.1 16.0
pilot area(irrigation)
2.3dry 5.4 4,9 20.4
wet 3.5 4.5 23.8
Layer ClassificationLayer Classification
Flood Deposit & Low Terrain
High Terrain
GW Model(MODFLOW)
2 Layers Conceptual Model
Upper Layer (Semi-confined)
Lower Layer (Confined)
10 km. 10
km Upper : 320 grids
Lower : 346 grids
Upper Layer
Lower Layer
Recent Flood Plain Deposits
Rock
Low Terrace Deposits
High Terrace Deposits
thickness 100-300 m.
thickness 40-100 m.
Calculation MethodCalculation Method1.1. Steady Calibration : 2003Steady Calibration : 20032.2. Transient Calibration : 1993-2003Transient Calibration : 1993-20033.3. Model Verification :2003-2005Model Verification :2003-2005
1.Steady Statefor Hydraulic Conductivity
2.Transient State for Specific Storage
1993 2003
3.Verification
2005
Calibration Calibration & &
VerificationVerification15
20
25
30
35
40
45
50
55
60
15 20 25 30 35 40 45 50 55 60
Computed vs. Observed ValuesH e a d
Co
mp
ute
d
Observed
10
20
30
40
50
60
70
80
10 20 30 40 50 60 70 80
Computed vs. Observed ValuesTra ns. H e a d
Co
mp
ute
d
Observed
Calculation
Average Error (m)
Root Mean Square Error(m)
Calibration Calibration (Steady)(Steady)
-0.-0.9797
27.27.55
Calibration Calibration (Transient)(Transient)
3 .83 .833
45.45.33
VerificationVerification
(Transient)(Transient)17.17.77
53.53.44
Steady
Transient
Watersituation
water demand : SW : GW(all in dry season)
Wet 1 : 0.49 : 0.27
Normal 1 : 0.32 : 0.36
Dry 1 : 0.47 : 0.52
Drought 1 : 0.63 : 0.68
Aquifer typespump yield
GW useto demandM3/hr
flood deposits 10-20 17%
Low terrace deposits 5-12 7%
high terrace deposits 1-10 2%
Basinwater demand : SW : GW
Irrigation area rain-fed area
Ping 1 : 0.54 : 0.08 1 : 0.83 : 0.17
Yom 1 : 0.90 : 0.01 1 : 0.87 : 0.13
Nan 1 : 0.53 : 0.30 1 : 0.97 : 0.03
Chaophraya 1 : 1.00 : 0.02 1 : 0.99 : 0.01
Sakaekrang 1 : 0.83 : 0.01 1 : 0.99 : 0.01
all basins 1 : 0.62 : 0.17 1 : 0.93 : 0.07
Irrigation condition water demand : SW : GW (all in wet year)
rainy season dry season whole year
irrigation area 1 : 0.74 : 0.05 1 : 0.50 : 0.29 1 : 0.66 : 0.13
rain-fed (no irrigation) 1 : 0.98 : 0.02 1 : 0.54 : 0.46 1 : 0.94 : 0.06
GW UseRatios
Space Dimension
Time Dimension
Conjunctive Use Patterns
0%
5%
10%
15%
20%
25%
30%
35%
40%
Wet Dry Wet Dry Wet Dry Wet Dry Wet Dry Wet Dry Wet Dry Wet Dry Wet Dry Wet Dry
1996 1997 1998 1999 2000 2001 2002 2003 2004 2005
Ra
tio
of
Gro
un
dw
ate
r U
se t
o T
ota
l w
ate
r d
ema
nd
(%
)
400
600
800
1000
1200
1400
1600
1800
2000
2200
2400
1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Wa
ter
Use
(Mil
lio
n m
3 /yea
r)
Surface Water Use
Ground Water Use
Surfaceand
GroundwaterUse
Ratio ofGroundwater Use
to total water demand
Different GW Level from Different GW Level from Calculation ApproachCalculation Approach
33
34
35
36
37
38
39
40
2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 Year
Gro
un
dw
ate
r L
ev
el
(m M
SL
)
gw level with conjunctive pattern approach
gw level with average pumping rate approach
gw level with 0.7% growth-rate approach(3) conjunctive patern
(1) average pumping rate(2) 0.7% increasing pumpinge rate
Groundwater Level in Mae Nam Yom basin
17
19
21
23
25
27
29
2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025
Gro
un
dw
ater
Lev
el (
m.M
SL
)
Groundwater Level
Moving average12-month moving average
Application#1 : GW Level in pilot areaApplication#1 : GW Level in pilot area GW yield awareness
Simulated asDrought year
Agricultural well yield
Application#2 :Application#2 :Regional GW tableRegional GW table
2005 2018
Simulated groundwater table using conjunctive use ratio
Questions & AnswersQuestions & Answers