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In Rwanda, 40% steep slope land and rapid growing urbanization increase susceptibility of land to stormwater runoff. The objectives were to analyze causal factors of stormwater runoff in the study area, to identify the extent to which the study area is susceptible to stormwater runoff, and to generate stormwater runoff susceptibility map of the study area. The study area is Nyabugogo catchment which crosses the districts of the Eastern Province (Kayonza, Rwamagana, and Gatsibo), the Northern Province districts (Gicumbi and Rulindo), and other districts of Kigali city (Kicukiro, Nyarugenge, and Gasabo districts). The authors employed secondary datasets collected from the United States Geological Survey (USGS), ranging between 2017 and 2020. Six triggering factors: Land Use and Land Cover (LULC), Rainfall, the duration of photosynthetic activity (NDVI), soil texture, Elevation, and the Slope were analyzed. The results indicated that poor land use and land management ranked 36.10%, rainfall 28.70%, and NDVI which ranked 16.40% are the main triggering factors. The results proved that Moderate, High and Very High Susceptibility to storm water runoff at large extent are recorded in Rulindo and Gicumbi districts of Northern Province, a large part of Gasabo and Nyarugenge districts in Kigali City, and parts of Gatsibo and Rwamagana districts, in Eastern province. It was concluded that if Best Management Practices (BMPs) are applied, flooding and erosion along with pollution can be minimized. The policy makers are recommended to consider the prone areas identified by this study and assign them the priority for stormwater runoff management plan.

The reduction of landslide losses requires appropriate method to reveal prone areas, causal factors and future occurrence likelihood. This study compared the effectiveness of the Statistical Index ...

— Smallholder farmers across the world and particularly in developing countries have been facing a problem of food insecurity and slow rate of livelihoods improvement because of climate-induced droughts and lack of effective use of modern agricultural techniques. Rainfall patterns have become more unpredictable and inconsistent with the traditional farming seasons and practices. Faced with such challenges, together with the rising population growth and its pressure on natural resources as well as strategies to eradicate hunger, many governments adopted irrigation systems and wetlands development for agriculture to improve food security and welfare of farmers and community in general. This study aims to analyse whether and the extent to which the development of Rwinkwavu marshland and introduction of irrigation system for rice growing in the area have been impacting on the community’s livelihoods improvement since the development of the marshland in 2014. Among the methodological approaches and tools used, a comprehensive desk review to explore available related research works in order to trace the gaps, field visit for researcher’s own observation and collection of information on site and available data in different institutions, exploration of satellite imagery of the study area and combination of primary and secondary data to allow the comparison of land use and cover changes before and after the marshland development, questionnaire and focused group discussions were used to collect the farmers and community’s view on the role of marsland transformation in livelihoods improvement. In addition, GIS was used to analyse and process spatial data of the land use/cover change of the area while collected data on community’s view were processed in Microsoft Excel and analyzed using SPSS. The findings indicate that the Rwinkwavu marshland reclamation and transformation to modern rice growing area has highly and positively contributed to community livelihoods improvement. It was recommended further researches in other reclaimed areas countrywide in order to allow decision makers to have enough data that help to compare the efforts and investments made in the sector with the impacts on population. Further researches to compare and balance the benefits from transformation made with the benefits from on natural ecosystem services as well as the impacts on natural habitat are also recommended.

— The problem caused by agricultural sector to Water Quality pollution remains a big challenge for Rwanda Government. The general objective of the study was to assess the potential effect of agricultural activities on water quality in Nyagatare District. Specifically, the study assessed agricultural activities in around Muvumba River, examine the level of water quality pollution in Muvumba River, and reveal the relationship between agricultural activities and water quality from Muvumba River. Data collected through interview, and laboratory tests of water samples applied once per month in three points sampling of Muvumba River. The action starting from 19th March 2019 up to 20th March 2020. To determine the correlation between agricultural input and Water Quality data at all selected physic-chemicals parameters, by Linear Regression Model using SPSS statistics with 95% confidence interval. The results indicated that agricultural activities on surrounding of Muvumba River, are presented by the existence of different type of crops, non-protection of anti-erosions, non-wetland margins, the farmers using chemical fertilizers and pesticides, the results revealed also that all selected parameters have not addressed positive relationship or pollution, but many of them did, as per to Rwanda Standards Board guidelines. For sampling point one has taken as baseline because it is upstream of Muvumba river at Nyagatare District, in sampling point 2, the parameters that presented pollution were; turbidity (r=0.193), nitrites (r=0.393), iron(r=0.122), manganese (r=0.008); for the sampling point3: were pH (r=0.319); turbidity (r=0.212); nitrites (r=0.143); nitrates (r=0.618); nitrogen ammonia (r=0.441); Iron(r=0.889); manganese (r=0.269); agricultural activities in surrounding of Muvumba River have significantly contributed to the water quality pollution of Muvumba River, through substances of chemical fertilizers, crop residues, and soil sediments that are transported into the River by erosion. Conclusion of the study that creation of anti-erosions in a surrounding Muvumba River areas, protection of buffer zones, performing vegetation covers, inducing water management bodies at cells level, introducing awareness of farmers how ecosystem functions.

— Hospitals produce relatively huge amount of wastewater containing pathogenic microorganisms, toxic, laboratory and pharmaceuticals residuals, disinfectants, biodegradable, polluters and radioactive contaminants that are potentially threats to population health and the components of environment when they are discharged without proper treatment. The purpose of the study was the assessment of water quality effluent from CHUK wastewater treatment plant (CHUK WWTP) by analyzing physico-chemical and bacteriological parameters. Sampling has been take place at different points and time better understanding of how hospital unit operations affect the effluent quality. A sum of twelve (12) samples were collected in three (3) trials at four (4) different points in Nyarugenge, Gitega and at the border with Kimisagara sector especially Mpazi stream where CHUKWWTP’s effluents are discharged. Samples collection, conservation, preparation and measurement took place at university of Rwanda-college of science and technology (CST) laboratory. The obtained results at WWTP outlet, at point of meeting with Mpazi stream, Mpazi stream and mixture of Mpazi stream with CHUK effluent were Cu (0.06, 0.07, 0.05 and 0.07mg/l); Fe (0.13, 0.037, 0.037 and 0.034mg/l); Pb (0.021, 0.024, 0.024, and 0.027mg/l); Hg (0.0015, 0.003, 0.003 and 0.004 mg/l) respectively. pH (7.25, 812,7.74 and 7.4); COD (215.5, 122.4, ,145.5 and 187.2mg/l); BOD5 (29.3, 30.85, 29.4 and 27.3 mg/l); TN (3.29, 2.97,3.2 and 3.46 mg/l); TP (1.05, 0.91, 0.92 and1.05mg/l); NH4+(7.46, 8.5,7.5and 8.8 mg/l); TSS (77, 56.5,62.8 and 69.1mg/l); fecal (282, 263,270, and 273 CFU/ml) and TC (233, 213, 224 and 210 CFU/ml). These parameters are prescribed within the reference limits of Rwanda Standard Board (RSB) and World Health Organization (WHO) standards, thus they have no negative side impact and effects on the receiving environments and their components.

— A challenge of linking agricultural sector with water quality in order to combat water pollution remains worrying for the Government of Rwanda. The general objective of the study was to assess the potential impacts of agricultural practices on water quality in NYANZA District. Specifically, the study assessed agricultural practices in Bishya wetland, analyzed the level of water pollution in Bishya wetland, and demonstrated the correlation between agricultural practices and water quality from Bishya wetland. Data were obtained through questionnaires, observation, and laboratory analysis of water samples taken twice per month in six sampling points of bishya dam situated in bishya wetland starting from 4th March 2019 up to 20th August 2019. The Linear Regression Model using SPSS statistics with 95% confidence interval was used to demonstrate the correlation between agricultural inputs and water quality data for all selected physico-chemical parameters. Findings revealed that agricultural practices in Bishya wetland and surrounding areas are characterized by the presence of different crops, ineffective anti-erosions, absence of wetland margins, ineffective drainage of wetland, use of organic manures and chemical fertilizers, as well as the presence of different types of rocks and soils. Findings revealed also that all parameters have not manifested pollution, but some of them did according to Rwanda Standard Board guidelines. In sampling point1, the parameters that presented pollution were nitrites (r=0.047), phosphates(r=0.384), iron (r=0.11), and manganese(r=0.018); in sampling point2, were nitrites(r =0.010), iron (r=0.059), and chemical oxygen demand(r=0.012); in sampling point 3, were pH (r=0.048), nitrites(r =0.086), and phosphates (r=0.329); in sampling point 4, were nitrites (r =0.123), iron(r=0.182), and manganese (r=0.051); in sampling point 5,were turbidity (r=0.080), nitrites (r=0.095), phosphates(r=0.188),iron(r=0.093), manganese(r=0.051), and chemical oxygen demand(r=0.017), and in sampling point 6, the parameters that presented pollution were nitrites(r=0.046), phosphates(r=0.277), iron(r=0.106), and manganese(r=0.190). Finally, findings revealed that agricultural practices in Bishya wetland and surrounding areas, have contributed to the pollution of water quality of Bishya dam through substances of organic manures, chemical fertilizers and pesticides, crop residues, and soil sediments that are transported into the dam by erosion. The study concluded that an effort to create anti-erosions in all areas surrounding wetland, respectful of buffer zones, improving vegetation covers, creating water management bodies at cells level, increasing awareness of population about ecosystem functions, and capturing rain water from houses may effectively contribute to water quality in Bishya wetland.