Water hyacinth (Eichhornia crassipes) is a potential accumulator of water pollutants in aquatic ecosystems, and its presence in water systems can affect water quality. This study used different field measurements and laboratory tests of lake water to determine the impact of water hyacinth phytoremediation capacity. A total of eight sampling stations were used for the two lakes: Lake Koka and Lake Ziway, Ethiopia. Sampling stations were selected from sites infested with water hyacinth (low, medium, and high) and non-water hyacinth aquatic plants during wet or rainy and dry or non-rainy seasons to compare the effects of plants on water quality in the two lakes. All the sampled stations had various human interventions. The water samples were tested for the selected physico-chemical properties, namely, phosphate, nitrate, pH, electrical conductivity (EC), the five-day biological oxygen demand (BOD₅), water temperature, and heavy metals (Chromium (Cr), Lead (Pb), Cadmium (Cd), Zinc (Zn), and Copper (Cu)). These water quality variables were compared by means of ANOVA. Despite the chemical oxygen demand (COD) of Lake Ziway, this study found no significant (p > 0.05) variation in the concentrations of Cu, EC, pH and water temperature between wet and dry seasons in either lake. Variations in Zn concentration and other physico-chemical parameters (EC, BOD₅, COD, nitrate, phosphate) between low, medium, and high levels of water hyacinth were significant in both lakes (p < 0.05). Water hyacinth has shown significant phytoremediation nature during wet and dry seasons. The lowest average heavy metal, phosphate, and nitrate concentrations; and significant pH and temperature variations were observed in Lakes Koka and Lake Ziway, among water hyacinth and other grass-infested sites. These findings suggest water hyacinth plant as a promising nature-based solution for removing undesirable chemicals from contaminated water bodies.

The water hyacinth is categorized among the world’s top ten worst invasive plant species of aquatic ecosystems. This study assessed changes in the spatiotemporal distributions of the water hyacinth in Lake Koka and Ziway of the Upper Awash River basin during the peak growth season of the plant. Household questionnaires and key informant interviews along with Landsat images for 2013, 2017, and 2021 were collected to identify the past, present, and future potential distributions of the invasive plant in the two lakes. Household surveys and key informant interviews were prepared using the Kobo Toolbox which monitors data collection online. A total number of 413 households were sampled and the data were analyzed through descriptive statistics. For Landsat images, a supervised classification technique was applied to classify the land use classes using the maximum likelihood algorithm. The survey results showed increased water hyacinth expansion in the area since the year 2011. The water hyacinth expansion affected 285 households’ livelihoods by invading 69.0% of their farmlands which caused 97.6% food scarcity in the study districts. The results of the Landsat image indicated that the water hyacinth invasion in Lake Koka occupied 1.48% in 2013, and this increased to 7.13% in 2021, while the water body decreased from 75.94 to 69.90%, respectively. However, the area of the other vegetation is nearly identical between the years 2013–2021. Likewise, water hyacinth covered 4.66% of Lake Ziway in 2013, and this was raised to 8.42% in 2021. At Lake Ziway water hyacinth invasion affected the area of other vegetation coverage as it decreased from 16.19 to 10.67% but the area of the water body remained almost the same during the years. Between 2013 and 2025, the amount of water hyacinths increased in both Lake Koka and Lake Ziway. According to LULC data, the water hyacinth's rate of spread was 0.56% in Lake Koka and 0.95% in Lake Ziway. The results of this study revealed the signals of LULC change due to water hyacinth invasion in the Upper Awash Basin which is considered an important aspect for future water resources planning and management.

Invasive alien plant species cause severe socio-economic and environmental damage. In particular, the water hyacinth ( Eichhornia crassipes ) is an aggressive alien aquatic macrophyte that affects the socio-hydrologic and social environment in many parts of the globe. This study assessed the socio-economic and ecological impacts of the water hyacinth (WH) in Koka and Ziway Lakes in Ethiopia and recommends novel management practices. Purposive sampling design method was used to select households using systematic random sampling. The household sample size was determined with 95% confidence level. Data were collected through key informant interviews, focus group discussion and household surveys, prepared using the Kobo Toolbox which monitors data collectors online. A total of 413 households were sampled and the data were analysed through descriptive statistics and the ANOVA statistical package. At Lake Koka districts that the WH has caused 51% food insecurity by reducing food productivity, and 98.5% health distress through exposure to vector disease. At Lake Ziway districts it caused 81.6% food insecurity and 99.5% health distress. At both lakes, the WH affected the fishing industry by almost 100%. In terms of crop production, maize was significantly affected at Koka, ᵡ ² (1, = 413) = 117.01, p<.001 and cabbage was significantly affected at Ziway, ᵡ ² (1, N= 413) =6.36, p<.001. There was a statistically significant difference in annual income level, age of the household leader, and cost of recovery at household family size, F (9, 623.18) =14.38, p<.001; Wilk’s Λ=.632, partial η2=.14. Therefore, 195 (99.5%) households at Lake Koka and 215 (99.1%) at Lake Ziway illustrated the need for intervention to reduce health impacts and food insecurity. Despite the negative impact, at Lake Koka districts, 86.7% of the plant is used as cattle feed and 28.1% as fertilizer. At Lake Ziway, 42.9% of the plant is used as forage and 39.2%, as a fertilizer.

The water hyacinth is categorized among the world’s top ten worst invasive plant species of aquatic ecosystems. This study assessed changes in the spatiotemporal distributions of the water hyacinth in Lake Koka and Ziway of the Upper Awash River basin during the peak growth season of the plant. Household questionnaire and key informant interview along with Landsat images for 2013, 2017, and 2021 were collected to identify the past, present, and future potential distributions of the invasive plant in the two lakes. Household surveys and key informant interview prepared using the Kobo Toolbox which monitors data collection online. A total number of 413 households were sampled and the data were analyzed through descriptive statistics. For Landsat images a supervised classification technique was applied to classify the land use classes using the maximum likelihood algorithm. The survey result shown in increased water hyacinth expansion in the area since the year 2011. The water hyacinth expansion affected 285 households livelihood by invading 69.0% their farm lands that caused 97.6% food scarcity on the study districts. The results of Landsat image indicated that the water hyacinth invasion in Lake Koka occupied 1.48% in 2013, and this raised to 7.13% in 2021, while the water body decreased from 75.94–69.90%, respectively. However, the area of the other vegetation is nearly identical between the years 2013–2021. Likewise, water hyacinth covered 4.66% of Lake Ziway in 2013, and this was raised to 8.42% in 2021. At Lake Ziway water hyacinth invasion affected the area of other vegetation coverage as it decreased from 16.19–10.67% but the area of the water body remained almost the same during the years. Between 2013 and 2025, the amount of water hyacinths increased in both Lake Koka and Lake Ziway. According to LULC data, the water hyacinth's rate of spread was 0.56% in Lake Koka and 0.95% in Lake Ziway. The results of this study revealed the signals of LULC change due to water hyacinth invasion in the Upper Awash Basin that to be considered as important aspect for future water resources planning and LULC management.