Assefa Gudina Muleta ^1* Dagne Getachew Woldemedhin ² Aseffa Seyum Wodajo ³ Feyera Senbeta Wekijira ³ Engdawork Assefa Tilahun ³ Afework Alemayehu Awasho ⁴

• ¹ Eastern Nile Technical Regional Office, Nile Basin Initiative, Addis Ababa, Ethiopia
• ² Salale University, College of Agriculture and Natural Resource, Fiche, Ethiopia
• ³ Addis Ababa University, College of Development Studies (CDS), Addia Ababa, Ethiopia
• ⁴ Urban development and transformation cluster, Training Institute, Ethiopian Civil Service University, Addis Ababa, Ethiopia

Water hyacinth spans extensive geographic areas in tropical and semi-tropical regions. Its impact on livelihoods is connected to the production of crops, fish, livestock, and other activities that influence costs and returns for rural smallholders. This invasive weed affects crop production by invading farm land adjacent to the lakes and has also an impact on livestock by covering grazing land meant for animal feed. Although several studies have been conducted in Ethiopia, the livelihood impact of water hyacinth has been scarcely analyzed, quantified, and documented. This study evaluates the adverse effects of water hyacinth, particularly on crop production, livestock management, fish harvesting, and other off-farm incomes by comparing groups of respondents' proximity to lakelake lake Koka and Demel in the Central Rifty-valley of Ethiopia before and after a specified period. Data were collected from 348 sample households based on the nearness of farm lands' to the lakes both adjacent to (≤ 300m) and distant from invaded lakes, six focus group discussions, six key informant interviewstre and field observations to assess the impact using Propensity Scores, Difference-in-Differences, and Weighted Least Squares methods. The result of Difference-in-Differences shows a decline in the total annual income by 823 ETB, income from crop production by 329 ETB per year, and income from offfarm activities by 6952 ETB per year for those living adjacent to the invaded lakes. Although the impact varies according to the intensity of the water hyacinth infestation, it adversely affects rural livelihoods by reducing crop yields and returns from off-farm activities. The study did not find any significant impact on livestock production and harvested fish. Other control variables such as education, experience, and interactions like dependency-age, experience-education, and land-lake also influenced the livelihood impact. As hypothesized, water hyacinth has caused differences in on-farm and off-farm incomes between groups of respondents. Further research is suggested to investigate the fish species favored and affected by this invasive weed. Ultimately, the impact of water hyacinth is of significant interest to affected communities, regional offices, policymakers, and scientists.