Kamuzu Barrage was commissioned in 1965 to regulate the water supply to meet water demand to downstream users including hydropower stations and protect them from aquatic weeds. After 2002 the invasion of water weeds became as severe that in floating weeds damaged the weed screens at Kamuzu and invaded hydropower stations downstream frequently caused forced shutdown of electricity generation and millions of dollar loss to economy. Since 2005, ESCOM started mechanical control of weeds procuring equipment but water weed problem remained as before due to ever increasing growth in the upstream. The government has undertaken weed management studies under the Shire River Basin Management Project of World Bank. Objective of the study is to envisage and recommend sustainable, economic and environment friendly management of weeds both pre-harvest (infestation, proliferation, invasion) and pro-harvest (collection, transportation and disposal convertible uses) situations. Consultants are responsible for recommending alternative weed control measures reducing their growth at source and economic / convertible uses of weeds after harvesting.
The Consultants provided following services:
• Review of the existing weed infestation problems and weed management system including method of collections, transportation, disposal/and use by communities
• Analysis of the pre-harvesting situation of infestations, proliferation and invasion at barrage and sub-sequent attacks to hydropower plants and suggesting pre-harvest control measures introducing biological and chemical control to reduce the rate of growth of weeds. Recommending biological control introducing weevils, etc. and use of herbicides where necessary taking all precaution
• Review of the MCA recommendations and analysis of the feasibility of improving existing weed management system strengthening mechanical control measures and enhancing efficiency of the system
• Review of the weed collection data and analysis of utilization methods of converting wastes into beneficial uses. The Consultants recommended production of biogas, organic manure and/or fuel briquette from weeds and their relative application and success. The project was funded by WB.
Client: Government of Malawi, Malawi, 2017