IMPACTS OF AGRICULTURAL WATER MANAGEMENT INTERVENTIONS ON THE HYDROLOGY OF THE WHITE VOLTA RIVER...

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IMPACTS OF AGRICULTURAL WATER MANAGEMENT INTERVENTIONS ON THE HYDROLOGY OF THE WHITE VOLTA RIVER BASIN: THE CASE OF DAMS AND DUGOUTS. Joachim A. Abungba 1 , Samuel N. Odai 1 , Frank O. Annor 1,2 , 3 Maxwell Boateng-Gyimah and Geoffrey Anornu 1 Abstract The reduction of flows into the White Volta is not only due to evaporation but also other factors such as continuous development of reservoirs and dugouts, although some of these reservoirs have problems with construction and boring of dam walls by crocodiles which leads to seepage. Results show a significant reduction in flow between 2017 and 2028 and beyond 2031. Specific irrigation schemes like Tono and Vea will record the highest unmet demand of about 0.00045Mm 3 between 2038 and 2039. More reservoir development should be coordinated and targeted at improving the existing ones before any new development. Conclusions Small reservoirs are a major component of the people’s farming activities with over 239 of such reservoirs dotted across the length and breadth of the region. About eighty-five percent (85%) of reservoirs from the study are in good condition and are therefore supporting agricultural production through dry season irrigation in the area. Both Tono irrigation scheme in the Nawuni catchment will be hard hit in terms of unmet water demands especially from the year 2032 to 2040. Pictures CGIAR Challenge Program on Water and Food P.O. Box 2075,127 Sunil Mawatha Pelawatta, Battaramulla, Sri Lanka T: +94 11 288 0143 F: +94 11 278 4083 E: [email protected] www.cgiar.org www.waterandfood.org 1 Civil Engineering Department Kwame Nkrumah University of Science and Technology Kumasi, Ghana September 2013 Background and Purpose Agriculture is the main economic activity in the White Volta River Basin with agricultural water management activities contributing significantly to food security and income. Current situation: Agricultural water management practices such as the use of shallow wells with buckets/ water pumps, dugouts, small reservoirs with lined or earth canals, stone and earth bunds and water pumps in rivers and wells in river beds have become a growing phenomenon in the Basin (Laube et al., 2008). Uncertainty: Unfortunately no long-term data and projections on the impacts of further development of agricultural water levels are available (Martin and Van de Giesen, 2005). Main objective of our research is, to assess the Impacts of Agricultural Water Interventions on the Hydrology of the White Volta River Basin. Findings About CPWF The CGIAR Challenge Program on Water and Food was launched in 2002. CPWF aims to increase the resilience of social and ecological systems through better water management for food production (crops, fisheries and livestock). CPWF currently works in six river basins globally: Andes, Ganges, Limpopo, Mekong, Nile and Volta. CPWF is a member of the CGIAR Water, Land and Ecosystems Research Program. The program focuses on the three critical issues of water scarcity, land degradation and ecosystem services, as well as sustainable natural resource management. CGIAR is a global agriculture research partnership for a food secure future. Its science is carried out by the 15 research centers who are members of the CGIAR Consortium in collaboration with hundreds of partner organizations. Methodology Kwame Nkrumah University of Science and Technology, Ghana Desk Study Field Measurements of Reservoirs, Communities and institutional interactions. Calibration and Validation of the Model (WEAP) Application of Calibrated model and Analysis Report Measurement of reservoirs Model - impacts of AWMI Evaluate the state of Small Reservoirs N i ave obs i obs N i i est i obs Q Q Q Q 1 2 . . 1 2 . . ) ( ) ( 1 SR area Measurements District No. of SR Total Area (Ha) Bolgatanga & Talensi Nabdam 30 205.94 Kasena/ Nankana East & West 81 2277.35 Bawku West 17 187.65 Bawku Municipal, Binduri & Garu 67 632.94 Builsa 27 149.76 Bongo 17 549.2 TOTAL 239 4002.84 State of Small Reservoirs (Very good & Good- no seepage, no trees, less siltation); Fair- very poor (serious seepage, siltation, presence of trees) 0 10 20 30 40 Very good Good Fair Poor Very Poor N u m b e r o f S R ( s ) Condition Presence of trees on reservoir wall Silted reservoir Surface water Availability Reference Streamflow (below node or reach listed) Year: 2010, All months (12), River: White Volta River 3 \ Withdrawal Node 2 13 \ Withdrawal Node 10 31 \ Red Volta River Inflow 39 \ Sissili River Inflow 43 \ Nawuni GS Billion Cubic Meter 11.0 10.0 9.0 8.0 7.0 6.0 5.0 4.0 3.0 2.0 1.0 0.0 Mean runoff in the White Volta is estimated at 11.5 billion m 3 Very good reservoir Pre and Post Impact of Reservoirs (Pwalugu) 0 50 100 150 200 250 300 350 400 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015 Stream flow (cums) Year August Unmet water demands Kwame Nkrumah University of Science and Technology, Ghana Specific Catchment Water Availability Acknowledgement The author wish to thank the V1 project of the Challenge Program on Water and Food (CPWF) for the support with funds for the studies and fieldwork. Special thanks goes to Dr. Jennie Baron of SEI for her support. Upper East Region Country boundary White Volta Sub-basins Volta Sub-basins 2 Faculty of Civil Engineering and Geosciences Water Resources Section Delft University of Technology, Delft, Netherlands 3 Water Resources Commission Accra, Ghana Contact: [email protected]

description

Final Volta Basin Development Challenge Science Workshop, September 2013

Transcript of IMPACTS OF AGRICULTURAL WATER MANAGEMENT INTERVENTIONS ON THE HYDROLOGY OF THE WHITE VOLTA RIVER...

Page 1: IMPACTS OF AGRICULTURAL WATER MANAGEMENT  INTERVENTIONS ON THE HYDROLOGY OF THE WHITE  VOLTA RIVER BASIN: THE CASE OF DAMS AND  DUGOUTS.

IMPACTS OF AGRICULTURAL WATER MANAGEMENT INTERVENTIONS ON THE HYDROLOGY OF THE WHITE

VOLTA RIVER BASIN: THE CASE OF DAMS AND DUGOUTS.

Joachim A. Abungba1, Samuel N. Odai1 , Frank O. Annor1,2, 3Maxwell Boateng-Gyimah and Geoffrey Anornu1

AbstractThe reduction of flows into the White Volta is not only due to evaporation but also

other factors such as continuous development of reservoirs and dugouts, although

some of these reservoirs have problems with construction and boring of dam walls

by crocodiles which leads to seepage. Results show a significant reduction in flow

between 2017 and 2028 and beyond 2031. Specific irrigation schemes like Tono and

Vea will record the highest unmet demand of about 0.00045Mm3 between 2038

and 2039. More reservoir development should be coordinated and targeted at

improving the existing ones before any new development.

Conclusions Small reservoirs are a major component of the people’s

farming activities with over 239 of such reservoirs dotted

across the length and breadth of the region.

About eighty-five percent (85%) of reservoirs from the

study are in good condition and are therefore supporting

agricultural production through dry season irrigation in the

area.

Both Tono irrigation scheme in the Nawuni catchment will

be hard hit in terms of unmet water demands especially from

the year 2032 to 2040.

Pictures

CGIAR Challenge Program

on Water and Food

P.O. Box 2075,127 Sunil Mawatha

Pelawatta, Battaramulla, Sri Lanka

T: +94 11 288 0143

F: +94 11 278 4083

E: [email protected]

www.cgiar.org www.waterandfood.org

1 Civil Engineering Department

Kwame Nkrumah University of Science and Technology

Kumasi, Ghana

September 2013

Background and PurposeAgriculture is the main economic activity in the White Volta River Basin

with agricultural water management activities contributing significantly to

food security and income.

Current situation: Agricultural water management practices such as the use

of shallow wells with buckets/ water pumps, dugouts, small reservoirs with

lined or earth canals, stone and earth bunds and water pumps in rivers and

wells in river beds have become a growing phenomenon in the Basin

(Laube et al., 2008).

Uncertainty: Unfortunately no long-term data and projections on the

impacts of further development of agricultural water levels are available

(Martin and Van de Giesen, 2005).

Main objective of our research is, to assess the Impacts of Agricultural

Water Interventions on the Hydrology of the White Volta River Basin.

Findings

About CPWF

The CGIAR Challenge Program on Water and Food was launched in 2002. CPWF aims to increase the resilience of social and

ecological systems through better water management for food production (crops, fisheries and livestock). CPWF currently works in six

river basins globally: Andes, Ganges, Limpopo, Mekong, Nile and Volta.

CPWF is a member of the CGIAR Water, Land and Ecosystems Research Program. The program focuses on the three critical issues

of water scarcity, land degradation and ecosystem services, as well as sustainable natural resource management. CGIAR is a global

agriculture research partnership for a food secure future. Its science is carried out by the 15 research centers who are members of the

CGIAR Consortium in collaboration with hundreds of partner organizations.

Methodology

Kwame Nkrumah University

of Science

and Technology, Ghana

Desk Study

Field Measurements of Reservoirs, Communities and institutional interactions.

Calibration and Validation of the Model (WEAP) Application of Calibrated model and Analysis Report

Measurement of reservoirs

Model - impacts of AWMI

Evaluate the state of Small Reservoirs

N

iaveobsiobs

N

iiestiobs

QQ

QQ

1

2..

1

2..

)(

)(1

SR area Measurements

District No. of SR Total Area (Ha)

Bolgatanga & Talensi Nabdam 30 205.94

Kasena/ Nankana East & West 81 2277.35

Bawku West 17 187.65

Bawku Municipal, Binduri &

Garu

67 632.94

Builsa 27 149.76

Bongo 17 549.2

TOTAL 239 4002.84

State of Small Reservoirs(Very good & Good- no seepage, no trees, less siltation); Fair- very poor (serious seepage, siltation, presence of trees)

0

10

20

30

40

Very good Good Fair Poor Very Poor

N

u

m

b

e

r

o

f

S

R(

s)

ConditionPresence of trees on reservoir wall

Silted reservoir

Surface water Availability

Reference

Streamflow (below node or reach listed)Year: 2010, All months (12), River: White Volta River

3 \

With

draw

al N

ode 2

13 \ W

ithdr

awal

Nod

e 10

31 \ Red

Vol

ta R

iver

Inflo

w

39 \ Si

ssili

River

Inflo

w

43 \ Naw

uni G

S

Billio

n C

ub

ic M

ete

r

11.0

10.0

9.0

8.0

7.0

6.0

5.0

4.0

3.0

2.0

1.0

0.0

Mean runoff in

the White Volta

is estimated at

11.5 billion m3

Very good reservoir

Pre and Post Impact of Reservoirs (Pwalugu)

0

50

100

150

200

250

300

350

400

1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005 2010 2015

Stre

am f

low

(cu

ms)

Year

August

Unmet water demands

Kwame Nkrumah

University of Science

and Technology, Ghana

Specific CatchmentWater Availability

AcknowledgementThe author wish to thank the V1 project of the Challenge Program on

Water and Food (CPWF) for the support with funds for the studies and

fieldwork. Special thanks goes to Dr. Jennie Baron of SEI for her support.

Upper East Region

Country boundary

White Volta Sub-basins

Volta Sub-basins

2 Faculty of Civil Engineering and Geosciences

Water Resources Section

Delft University of Technology, Delft, Netherlands

3 Water Resources Commission

Accra, GhanaContact: [email protected]