development and application of the drainage and irrigation ... · polder drain inriver norm inriver...

Development and application of the drainage and irrigation module of polders in plain river network region

Zhengqing Lai, Shuo Li, Yang Deng, Guonian Lvlzq0129lzq@163.com

7/29/2016

2016 International SWAT Conference

Key Laboratory of Virtual Geographic Environment

Nanjing Normal University

What We Will Cover…

Introduce the Polder Overview of Existing Techniques Introduce the Polder Module Analysis of Results

─ Drainage and Irrigation─ Watershed Outlet

Conclusion Q & A

Introduction—What is Polder?

Bridge

Building

TreeDike

Pond

Pumping Station

River

Paddy

Introduction—What is Polder?

A Polder

Introduction—What is Polder?

A Polder

Bridge

Building

TreeDike

Pond

Pumping Station

River

Paddy

Introduction—What is Polder?

Features of the Polder In low-lying areas

Bridge

Building

TreeDike

Pond

Pumping Station

River

Paddy

Introduction—What is Polder?

Features of the Polder In low-lying areas Enclosed by dikes Surrounded by rivers/lakes

Bridge

Building

TreeDike

Pond

Pumping Station

River

Paddy

Introduction—What is Polder?

Features of the Polder In low-lying areas Enclosed by dikes Surrounded by rivers/lakes Connect with outside through manually...

Introduction—Why model Polders?

Dikes cut off the connection Drainage and Irrigation Management Large numbers of Polders

Introduction—Why model Polders?

Polders in Taihu Lake Basin (Yan and Gao, 2015)

Introduction—Why model Polders?

River Network in Taihu Lake Basin

Existing SWAT modeling Methods in Polder Areas

Ignore the dikes of polders Single polder simulation Virtual Reservoir

Existing SWAT modeling Methods in Polder Areas

Ignore the dikes of polders Single polder simulation Virtual Reservoir

(Xu and Wang, 2010)

Objective

Modeling the drainage and irrigation processes of polder areas with improved SWAT

Drainage and Irrigation Modeling

Outside River

Ditch

Pump

Paddy

Culvert

Pond

FenceIrrigation Sluice

Intake Sluice

Outlet Sluice

Intake Culvert

Dike

Irrigation Process

Drainage Process

Inside Outside

Inside River

Outlet Pond

How Polders Work?

Drainage and Irrigation Modeling

Outside River

Ditch

Pump

Paddy

Culvert

Pond

FenceIrrigation Sluice

Intake Sluice

Outlet Sluice

Intake Culvert

Dike

Irrigation Process

Inside Outside

Inside River

Outlet Pond

How Polders Work?

Drainage and Irrigation Modeling

Outside River

Ditch

Pump

Paddy

Culvert

Pond

FenceIrrigation Sluice

Intake Sluice

Outlet Sluice

Intake Culvert

Dike

Drainage Process

Inside Outside

Inside River

Outlet Pond

How Polders Work?

Drainage and Irrigation Modeling Drainage

After DrainageBefore Drainage

Normal Level

Upper Limit Level

Inside River

Inside River

Drainage and Irrigation Modeling Irrigation

Time(days)

Cro

p co

effic

ient

/ K

c

InitialCrop

development Mid-season Late season

Kc ini

Kc mid

Kc end

Time(Month/Da

y)

Irrigation regime

(water depth)

Crop coefficient（KC）

6/15–6/21 5-30mm 0.942

6/22–7/9 0-30mm 0.942

7/10–7/19 Drain out KC=0.0218t+0.396

7/20–8/30-30mm

(delay 3 days)KC=0.0218t+0.396

8/4–8/80-30mm

(delay 3 days)1.488

8/9–9/70-20mm

(delay 3 days)1.488

9/8–10/170-10mm

KC=-0.0219t+3.68

Irrigation regime

Crop coefficient (FAO)

Drainage and Irrigation Modeling Drainage and Irrigation Equations

lossirrdrainpcpinstore VVVVV −+−=

Drainage and Irrigation Modeling Drainage and Irrigation Equations

lossirrdrainpcpinstore VVVVV −+−=

>⋅⋅⋅≤⋅⋅−

=)(360024)(10)(

max

max6

VVqSVVSHH

Vdrainpolder

draininrivernorminriverdrain

310)( −⋅−⋅

+= lossinriver

polderinstoreinriver H

SSQ

HH

310⋅⋅= paddyirrirr SHV

Module Development Integrated with SWAT

subwatershed

Next subwatershed

ReservoirWater

transferIrrigation

Water use

Point source

Traspertation loss

Water loss or compensation

Remaining water

Module Development Integrated with SWAT

subwatershed

Next subwatershed

ReservoirWater

transferIrrigation

Water use

Point source

Traspertation loss

Polder regime

Water loss or compensation

Remaining water

Module Development Polder Input Files

Module Development—Program

Module Development—Program

Case Study—Study Area

Liyang Watershed

Case Study—Watershed Delineation

Sub-Watershed

Case Study—Parameters Definition

Case Study—Results

Drainage and Irrigation Simulation

0

50

100

150

200

250-15

-5

5

15

25

7/17 7/27 8/6 8/16 8/26 9/5 9/15 9/25 10/5 10/15

Prec

ipita

tion(

mm

)

Wat

er v

olum

e(m

3·10

4 )

Month/Day

Precipitation Observed

Drainage

Irrigation

Case Study—Results

Drainage and Irrigation Simulation

0

50

100

150

200

250-15

-5

5

15

25

7/17 7/27 8/6 8/16 8/26 9/5 9/15 9/25 10/5 10/15

Prec

ipita

tion(

mm

)

Wat

er v

olum

e(m

3·10

4 )

Month/Day

Precipitation Observed SWAT

Drainage

Irrigation

Case Study—Results

Drainage and Irrigation Simulation

0

50

100

150

200

250-15

-5

5

15

25

7/17 7/27 8/6 8/16 8/26 9/5 9/15 9/25 10/5 10/15

Prec

ipita

tion(

mm

)

Wat

er v

olum

e(m

3·10

4 )

Month/Day

Precipitation Observed SWAT Integrated SWAT

Drainage

Irrigation

Case Study—Results

Watershed Outlet Simulation

0

200

400

600

800

1000

12000

30

60

90

120

2010-01 2011-01 2012-01 2013-01

Prec

ipita

tion(

mm

)

Stre

am F

low

(m3/

s)

Year-Month

Precipitation Observed SWAT Integrated SWAT

Case Study—Results

Validation of the Results

Year

SWAT Integrated SWAT

R2 ENS R2 ENS

2010 0.68 0.65 0.83 0.69

2011 0.77 0.22 0.79 0.71

2012 0.67 0.45 0.78 0.74

2013 0.59 0.31 0.86 0.86

2010-2013 0.58 0.43 0.74 0.74

Conclusion

The new module is able to model the drainage and irrigation processes of polders

The integrated SWAT enhances the simulation accuracy of the streamflow of polder watershed

Benefit the distributed hydrological modeling in plain river network region

Thank You!

lzq0129lzq@163.com

Key Laboratory of Virtual Geographic Environment

Nanjing Normal University