The Okavango River Basin Challenges Opportunities OKACOM 2003

The Okavango River Basin – Challenges & Opportunities. OKACOM, 2003, Corvallis Several slides compiled by Dr Peter Ashton – CSIR (2002)

MAKGADI CATCHMENT ANGOLA N Cuando R. ZAMBIA Cuito R. Zambezi R. Cubango R. Kavango R. Okavango Delta Chobe R. ZIMBABWE Okavango Basin Nata R. Boteti River basin Omatako R. Lake Ngami Map sourced from GEF Report on Okavango Delta Study Sowa Pan basin Okwa R. NAMIBIA Ntwetwe Pan basin Deception Pan basin 100 km BOTSWANA R. S. A.

RAINFALL DISTRIBUTION ANGOLA 20° E M. A. P. (mm) 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 ZAMBIA 15° S Cuando R. Zambezi R. Cubango R. Cuito R. Kavango R. NAMIBIA Chobe R. Rundu Zambezi R. ZIMBABWE Savuti R. OKAVANGO DELTA 20° S Omatako R. Boteti R. L. Ngami Maun L. Xau BOTSWANA Makgadi Pans Nata R.

VARIABLE ANNUAL INFLOWS AT MOHEMBO (1933 - 2001) 180 Percentage of mean annual inflow 160 Max. : 16, 145 x 106 m 3 Mean: 9, 863 x 106 m 3 Min. : 5, 321 x 106 m 3 5 -year Moving average 140 120 100 80 60 40 1930 1940 1950 1960 1970 Time (Years) 1980 1990 2000

Outflow (106 m 3) Rainfall (mm) Inflow (106 m 3) TIMING OF DELTA RAINFALL INFLOW AND OUTFLOW Inflow Volume (Mohembo) 1000 500 0 Rainfall (Average of Shakawe plus Maun) 100 50 0 Outflow Volume (Thamalakane) 40 20 0 J J A S O N D J F M A M J J A S O N D J F M

DELTA WATER BALANCE RIVER INFLOWS + 76 % DIRECT RAINFALL + 24 % RIPARIAN SOILS & GROUNDWATER - 13 % DIRECT EVAPOTRANSPIRATION - 84 % OUTFLOW -3%

PROJECTED WATER NEEDS IN OKAVANGO BASIN Anticipated total water requirement = 300 million m 3 / year in 2020

RATIFIED INTERNATIONAL CONVENTIONS Treaty / Protocol Ratification Date Country Ramsar Angola UNCCD UNCSW UNFCCC 01/04/98 30/06/97 N/P 17/05/00 Botswana 09/12/96 12/10/95 11/09/96 N/P 27/01/94 N/P 19/05/95 Namibia N/P UNCBD 23/08/95 16/05/97 N/P = Not yet party to Treaty / Protocol

RAMSAR SITE LOCATION 15° E ANGOLA 20° E 15° S Cuando R. Zambezi R. Cubango R. Kavango R. NAMIBIA ZAMBIA Cuito R. Chobe R. Rundu Zambezi R. ZIMBABWE Savuti R. OKAVANGO DELTA 20° S Nata R. Boteti R. Omatako R. Maun L. Ngami Boundary of the Okavango Delta RAMSAR site L. Xau BOTSWANA Makgadi Pans

MOSAIC OF HABITATS The Okavango Delta has an enormous variety of different habitat types and a diverse array of aquatic and terrestrial species

OKAVANGO – CUITO CONFLUENCE Kavango River Cuito River ANGOLA NAMIBIA