Surface Water Balance in the Pecos River Basin

Pecos River, near Langtry, Val Verde County, Texas

Sedat Yalcinkaya

April 28, 2010

Surface Water Balance in the Pecos River Basin

Too much water but not when and where it is needed!

IPCC report “Climate Change and Water”, 2008

UN Millennium Development Goals “Food and Water Security”

The EU Water Framework Directive - Integrated River Basin Management for Europe

Water Resources Planning and Management

Surface Water Balance in the Pecos River Basin with ArcGIS

Runoff Analysis in the study area Application of WEAP

All the calculations were made for 1990 except runoff analysis

Study AreaLegend

Main_BASIN_Rivers

Orig_RioGrand_Total

Waterbody1

Watershed_Pecos

Basin_States<all other values>

NAME

CHIHUAHUA

COAHUILA

COLORADO

DURANGO

NEW MEXICO

NUEVO LEON

TAMAULIPAS

TEXAS

State_TX

Ü0 110 220 330 44055Miles

TEXAS

COLORADO

NEW MEXICO

CHIHUAHUA

COAHUILA

DURANGO

TAMAULIPAS

NUEVO LEON

WATERSHEDS (HUC_8) AREA (KM2)

13070001 6454.582529

13070003 2913.223075

13070004 5074.004481

13070005 1831.660091

13070006 3833.113807

13070007 16414.37423

13070008 4962.616022

13070009 2505.34438

13070010 1997.452143

13070011 2828.999238

13070012 2573.636942

TOTAL BASIN AREA 51389.006960

33.02 and 29.69 N Latitude104.65 and 101.14 W Longitude

Data Sources

CRWR Database NRCS, Geospatial Data Gateway NHDPlus NCDC NASA, Land Data Assimilation System

Processing the Climate Data

32 km cell size

Processing the Soil DataLayer Thickness Depth to Top

Depth to Bottom

1 5 cm (2 in) 0 cm (0 in) 5 cm (2 in)

2 5 cm (2 in) 5 cm (2 in) 10 cm (4 in)

3 10 cm (4 in) 10 cm (4 in) 20 cm (8 in)

4 10 cm (4 in) 20 cm (8 in) 30 cm (12 in)

5 10 cm (4 in) 30 cm (12 in) 40 cm (16 in)

6 20 cm (8 in) 40 cm (16 in) 60 cm (24 in)

7 20 cm (8 in) 60 cm (24 in) 80 cm (31 in)

8 20 cm (8 in) 80 cm (31 in) 100 cm (39 in)

950 cm (20 in)

100 cm (39 in)

150 cm (59 in)

1050 cm (20 in)

150 cm (59 in)

200 cm (79 in)

1150 cm (20 in)

200 cm (79 in)

250 cm (98 in)

First Bucket

Second Bucket

The resolution is 1/8 degree (~140 km2 per grid cell)

Simple Surface Water Balance with ArcGIS

outi QQEPdt

ds

P= PrecipitationE= EvaporationQ= Naturalized Flows

Precipitation and Evaporation

1307

0001

1307

0003

1307

0004

1307

0005

1307

0006

1307

0007

1307

0008

1307

0009

1307

0010

1307

0011

1307

0012

0

100

200

300

400

500

600

700

Sub Watershed

An

nu

al P

reci

pit

atio

n,

mm

Janu

ary

Febru

ary

Mar

chApr

ilM

ayJu

ne July

Augus

t

Septe

mbe

r

Octob

er

Novem

ber

Decem

ber

0

20

40

60

80

100

120

Months

Pre

cip

itat

ion

, m

m

1307

0001

1307

0003

1307

0004

1307

0005

1307

0006

1307

0007

1307

0008

1307

0009

1307

0010

1307

0011

1307

0012

0

50

100

150

200

250

300

350

400

Sub Watershed

An

nu

al E

vap

ora

tio

n,

mm

Janu

ary

Febru

ary

Mar

chApr

ilM

ayJu

ne July

Augus

t

Septe

mbe

r

Octob

er

Novem

ber

Decem

ber

0

10

20

30

40

50

Months

Eva

po

rati

on

, m

m

Water Balance

Janu

ary

Febru

ary

Mar

chApr

ilM

ayJu

ne July

Augus

t

Septe

mbe

r

Octob

er

Novem

ber

Decem

ber

0

1000

2000

3000

4000

5000

6000

Precipitation

Evaporation

Net Outflow

Months

Vo

lum

e, M

m3

Janu

ary

Febru

ary

Mar

chApr

ilM

ayJu

ne July

Augus

t

Septe

mbe

r

Octob

er

Novem

ber

Decem

ber

-1000

-500

0

500

1000

1500

2000

2500

3000

3500

4000

Months

Ch

ang

e in

Sto

rag

e, M

m3

It is likely that considerable amount of water was stored in the reservoirs exist along the basin.

Runoff Analysis

Janu

ary

Febru

ary

Mar

chApr

ilM

ayJu

ne July

Augus

t

Septe

mbe

r

Octob

er

Novem

ber

Decem

ber

0

10

20

30

40

50

60

Months

Vo

lum

e, M

m3

Rainfall vs Runoff

0 20 40 60 80 100 1200

0.2

0.4

0.6

0.8

1

1.2

1.4

f(x) = 0.241547965848808 exp( 0.0131780198918695 x )R² = 0.512639208424478

Rainfall, mm/month

Ru

no

ff,

mm

/mo

nth

For example; for a 40 mm rainfall can cause a 0.4 mm runoff

Hydrologic Modeling with WEAP

Adding Data to WEAP

WEAP Results0 \ Headflow 1 \ Catchment Inflow Node 12 \ Reach 3 \ tributary 7 Inflow4 \ Reach 5 \ tributary 6 Inflow6 \ Reach 7 \ tributary 5 Inflow8 \ Reach 9 \ Catchment Inflow Node 910 \ Reach 11 \ Tributary 4 Inflow12 \ Reach 13 \ tributary 3 Inflow14 \ Reach 15 \ Catchment Inflow Node 616 \ Reach 17 \ tributary 2 Inflow18 \ Reach 19 \ Tributary 1 Inflow20 \ Reach 21 \ Catchment Inflow Node 1122 \ Reach

Streamflow (below node or reach listed)Scenario: Reference, All months, River: Main River

Jan1990

Feb1990

Mar1990

Apr1990

May1990

Jun1990

Jul1990

Aug1990

Sep1990

Oct1990

Nov1990

Dec1990

Milli

on C

ubic

Met

er

3,800

3,600

3,400

3,200

3,000

2,800

2,600

2,400

2,200

2,000

1,800

1,600

1,400

1,200

1,000

800

600

400

200

0

Surface Runoff Precipitation Interflow Increase in Soil MoistureEvapotranspiration Decrease in Soil MoistureBase Flow

Land Class Inflow s and Outflow sScenario: Reference, All months

Jan1990

Feb1990

Mar1990

Apr1990

May1990

Jun1990

Jul1990

Aug1990

Sep1990

Oct1990

Nov1990

Dec1990

Milli

on C

ubic

Met

er

5,500

5,000

4,500

4,000

3,500

3,000

2,500

2,000

1,500

1,000

500

0

-500

-1,000

-1,500

-2,000

-2,500

-3,000

-3,500

-4,000

-4,500

-5,000

-5,500

Conclusion  1990 values in mm

  Precipitation Evaporation Runoff

Mean 35.4525 21.06 0.46

Max 107.9 43.92 1.2

Min 5.76 4.88 0.18 Most of the precipitation occurs in July,

August and September Precipitation gets the lowest level in winter Maximum evaporation occurs in August,

September and October Maximum runoff occurs in September and

October The water balance for 1990 indicates

shortage of water in May, June and December.

Questions??