Browsing by Author "Mutua, Benedict"

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  • Publication
    Publication
    Access to Water in Kenya’s Coast Region: A Challenge to Community Development and Poverty Alleviation in Lamu County
    (Kenya Aquatica Journal, 2018-11-30) Ignatius, David O.; Hassan, Farida A.; Morara, George N.; Osore, Melckzedeck K.; Mutua, Benedict; Kitaka, Nzula K.
    Water is considered a basic commodity and essential for life - living on planet earth is dependent on it. However, access to water has been and will continue to be a dilemma for a majority of the residents at the coast of Kenya. A close look at the window on “Coastal Resources and People” reveals that water is a key resource but despite its immense importance, many people especially in the rural areas and the Vulnerable and Marginalized Groups (VMG’s) do not have adequate access to potable, reliable and convenient sources of water. Lamu, currently considered among water scarce counties in Kenya as per the Lamu County Integrated Development Plan (http://lamu.go.ke/wp-content/uploads/2016/03/LAMU_CIDP-Revised.June_2014-1.pdf), faces serious challengeof provision of potable water to its residents. With the influx of people from other parts of the country as a result of the implementation of the Kenya Vision 2030 flagship project - Lamu Port Southern Sudan Ethiopia Transport Corridor (LAPSSET), the current water stresses is only expected to worsen. The Lamu County Government plans to address the ever-increasing demand for access to water but resources to actualise these plans are yet to be consolidated. To complement this situation, Kenya Coastal Development Project (KCDP), a World Bank funded project is working with local communities in Lamu in thedevelopment and implementation of community-led water projects targeting to increasing access to water at household level.This paper will focus on community-based approaches to understand the water-web in Lamu East Sub-County to provide an assessment of opportunities, challenges and sustainability implications. Primary data is used on surveys, Social Assessment (SA) Vulnerable and Marginalised Group Plan (VMGP), observations and recommendations from the Lamu CIDP. It further proposes that of direct usage of saline water, seawater or brackish water, for sanitation purposes could alleviate the freshwater shortage.
  • Publication
    Publication
    Analysis of spatial and temporal drought variability in a tropical river basin using Palmer Drought Severity Index (PDSI)
    (Acadamic Journals, 2017-08-31) Wambua, Raphael; Mutua, Benedict; Raude, James
    Analysis of spatial and temporal drought variability in the upper Tana River basin using Palmer Drought Severity Index (PDSI) was conducted. The drought is critical for formulation of mitigation measures in the river basin. A monthly temporal and 90-m spatial resolution was applied. This was achieved within ArcGIS environment. Climatic data for 1970 to 2010 was used for computation of the PDSI while the missing data sets were filled using Artificial Neural Networks (ANNs). The results of PDSI for dry and wet seasons at meteorological stations indicate that the time series plots for the PDSI values for dry season are generally lower than those for the wet seasons. The PDSI values for meteorological stations located at the lower elevation of the basin are lower than those located at higher elevation. On the other hand, spatially distributed drought severity based on PDSI show that the ranges of maximum and minimum drought severity values in 1970 are -0.868 to -0.804 and -0.675 to -0.610 respectively. These values of drought severity occur respectively in the north-western and south-eastern areas of the basin. PDSI values increased from the range -0.675 to -0.610 in 1970 and from -1.087 to 0.957 in 2010 for the north-eastern areas of the upper basin. The south eastern areas of the basin are more prone to drought risks than north-western parts. Use of the PDSI reflects the spatial heterogeneity and temporal variability of drought across the basin. The drought assessment offer technical approach for comprehensive understanding of drought for effective drought-induced disaster mitigation and its management, with a view to reducing adverse effects on livelihoods.
  • Publication
    Publication
    The Effect of Climate Change on Loss of Lake Volume: Case of Sedimentation in Central Rift Valley Basin, Ethiopia
    (MDPI, 2018-12-11) Takele, Gadissa; Nyadawa, Maurice O.; Fiseha, Behulu; Mutua, Benedict
    Evaluating the impact of climate change on sediment yield has become one of the major topics in climate research. The purpose of this study was to investigate sediment yield contribution to lake volume change under changing climatic conditions in the Central Rift Valley Basin. The ensemble mean of five regional climate models (RCMs) in the coordinated regional climate downscaling experiment (CORDEX)-Africa was considered for the purpose of this study. The climate variables (precipitation, minimum and maximum temperatures) in RCMs were bias corrected against observed data (1985–2016) using linear scaling (LS), power transformation (PT), variance of scaling (VS), and quantile mapping (QM). Two emission scenarios, the Representative Concentration Pathways, RCP4.5 and RCP8.5, were considered for the future scenario period (2041–2070). Better results were obtained when the ensemble values of the bias correction methods were used. Hence, the projected values of climate variables after bias correction were used in the Soil and Water Assessment Tool (SWAT) hydrological model to estimate the sediment yield contribution to lake volume change due to climate change. The results show that the average projected precipitation will decrease by 7.97% and 2.55% under RCP4.5 and RCP8.5, respectively. On average, the maximum temperature will increase by 1.73 °C and 2.36 °C under RCP4.5 and RCP8.5, respectively, while the minimum temperature will increase by 2.16 °C and 3.07 °C under RCP4.5 and RCP8.5, respectively. The average annual sediment yield contributions to Lake Ziway were 431.05 ton/km2 and 322.82 ton/km2 for the Meki and Ketar rivers, respectively, in the historical period (1985–2010). The study also reveals that the annual sediment yield that was estimated for the Meki River was 323 ton/km2 and 382 ton/km2 under RCP4.5 and under RCP8.5, respectively. The sediment estimations for the Ketar River were 157 ton/km2 and 211 ton/km2 under RCP4.5 under RCP8.5, respectively. This will decrease the rate of volume change in Lake Ziway by 38% under RCP4.5 and by 23% under RCP8.5. The results show that the life expectancy of the lake is likely to increase under climate change scenarios. This will help water resources managers make informed decisions regarding the planning, management, and mitigation of the river basins.