Browsing by Author "Tibebu Assefa"

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    Characteristics of Urban Recreational Parks and Visitation for Environmental and Social Benefits: The Case of Six Selected Parks in Addis Abab
    (Addis Ababa University, 2022-06-09) Tibebu Assefa; Aklilu Amsalu (Phd)
    Urban recreational parks have a role in providing environmental and social benefits. These benefits are not yet used due to lack of effective intervention that improve urban park characteristics which can attract the parks visitor’s interest as well as improve the environmental benefits. This study is aimed at investigating the role of park characteristics in providing environment and social benefits. For this, the study employed descriptive and inferential research design with mixed approaches. The data were collected from primary and secondary data sources. The primary data sources were a survey of 385 park visitors, three key informant interview, and researcher observation in the six recreational parks. The secondary data sources were from studies, government documents, online and off-lines materials. Sample recreational parks in the city were selected through a stratified purposive sampling basing the recreational park size and administrational level. The data were analyzed using descriptive and inferential analysis method. The qualitative data were analyzed using content analysis. Based on visitors’ response, it was found that recreational parks have environmental (78%) and social (65%) benefits. Among the park characteristics in the sampled parks, vegetation and climate comfort were the highest whereas accessibility, management and maintenance were ranked the lowest by park visitors. In addition, the findings indicated that better facilities, events in the parks and vegetation were among the major characteristics of park that attract visitors. Furthermore, it was found that 37.7% park visitors were visiting parks weekly. Moreover, 43.9% recreational park visitors usually spent 1 to 2 hours in recreational parks and about 82% of visitors preferred to come in weekends. The park visitors ranked the city parks and had set the criteria for ranking which is important to understand what attract visitors to visit a certain recreational parks. These findings indicated that the park characteristics has a relation with park visitation which has an impact in achieving environmental and social benefits from recreational parks.
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    Determining Ventilation Orientated Optimum Window Size for Urban Centers of Ethiopia
    (Addis Ababa university, 2020-11) Deriba Matias; Tibebu Assefa
    Natural Ventilation is an effective method for passive cooling, increase indoor air quality and minimize energy consumption of a building. Natural ventilation through window openings is an effective solution to bring air into internal spaces and improve indoor environmental condition. In urban centers, where the density is high and local wind is reduced, the geometry of a building and its opening has a massive role in natural ventilation. The current building codes and regulations of Ethiopia miss detailed guidelines for natural ventilation. On the code and regulation for windows are specified only in relation to the floor area regardless of orientation, height, location and climate. Since the country has different climate zone in different regions, the generalized building code and standard will lead to over or under ventilated rooms in both scenarios creates discomfort. The study attempt to determine ventilation-based window size for urban centers of Ethiopia on different façade orientation to increase the effectiveness of natural ventilation. As wind is the main driving force of natural ventilation, regionalizing of Ethiopia according to wind speed and wind direction (secondary-Inter cardinal direction) is presented in order to study the potential of natural ventilation at different regions in the country. The average wind speed is categorized using the Beaufort’s scale of wind speed. The data addresses the urban centers of Ethiopia and the urban centers are selected by density. Both scenarios (single side ventilation and cross-ventilation) are discussed in each zone. Appropriate opening size is determined, using the window orientation with respect to the wind flow direction and also best and worst window orientation is illustrated for each zone. The study verified that, the effectiveness of natural ventilation is associated with wind zone where the urban centers are located.
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    Improving the Thermal Qualities of the Existing Streets of Dire Dawa City by Using Urban Design Elements
    (Addis Ababauniversity, 2016-12) Asmamaw Ayele; Tibebu Assefa
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    Leveraging On-Site Rainwater Harvesting For Water Supply Challenges of High-Occupancy Mixed-Use Buildings In Addis Ababa; The Case of Crown Hotel 40/60 Condominium
    (Addis Ababa University, 2024-05-01) Ashenafi Belina Hunde; Tibebu Assefa
    Addis Ababa City Administrations has built different types of condominium housing since 2005 through its Housing Development Program. 40/60 condominium is one of the program schemes intends for higher middle income residents. However, most of these housing sites supplied water twice a week. This research aims to investigate the water supply demand gap as well as potential rooftop and surface runoff RWH for supplementary water supply and flood reduction in Crown Hotel 40/60 condominium site. Monthly water demand is projected from household survey data collected from 193 residential and commercial units; the current water consumption determined from six-month monthly water bill. Rooftop RWH potential of site is calculated by interpolating the mean monthly rainfall data of 15 rain gauge stations collected from National Meteorological Agency. As well as, the catchment hydrology is analyzed using rational methods; infiltration trench and basin is proposed for surface runoff harvesting in accordance to the catchment suitability criteria. The result indicates, the study site has a monthly water supply gap of 0.41m3 per housing units. Each buildings have rooftop RWH potential of 1190.2m3 annually, this amount can contribute 11 percent of the buildings annual water demand. The required size of infiltration trench and basin are 14.72m2 for trench and is 22.7m2 basin. These components have a potential of 22,511.28m3 surface runoff harvesting annually by infiltrating to ground soil. Both rooftop and surface RWH system can reduce 63 percentages of floods generated from the study site. Thus, practicing both surface and rooftop RWH systems are comprehensive to encounter the city water supply challenges and flood related problems caused by the combination of population growth, climate and land use change. Keywords: Water sensitive urban design, water; rooftop rainwater harvesting; surface runoff, stormwater, 40/60 condominium
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    Leveraging on-Site Rainwater Harvesting for Water Supply Challenges of High-Occupancy Mixed-Use Buildings in Addis Ababa; The Case of Crown Hotel 40/60 Condominium
    (Addis Ababa University, 2024-05-01) Ashenafi Belina Hunde ; Tibebu Assefa
    Addis Ababa City Administrations has built different types of condominium housing since 2005 through its Housing Development Program. 40/60 condominium is one of the program schemes intends for higher middle income residents. However, most of these housing sites supplied water twice a week. This research aims to investigate the water supply demand gap as well as potential rooftop and surface runoff RWH for supplementary water supply and flood reduction in Crown Hotel 40/60 condominium site. Monthly water demand is projected from household survey data collected from 193 residential and commercial units; the current water consumption determined from six-month monthly water bill. Rooftop RWH potential of site is calculated by interpolating the mean monthly rainfall data of 15 rain gauge stations collected from National Meteorological Agency. As well as, the catchment hydrology is analyzed using rational methods; infiltration trench and basin is proposed for surface runoff harvesting in accordance to the catchment suitability criteria. The result indicates, the study site has a monthly water supply gap of 0.41m3 per housing units. Each buildings have rooftop RWH potential of 1190.2m3 annually, this amount can contribute 11 percent of the buildings annual water demand. The required size of infiltration trench and basin are 14.72m2 for trench and is 22.7m2 basin. These components have a potential of 22,511.28m3 surface runoff harvesting annually by infiltrating to ground soil. Both rooftop and surface RWH system can reduce 63 percentages of floods generated from the study site. Thus, practicing both surface and rooftop RWH systems are comprehensive to encounter the city water supply challenges and flood related problems caused by the combination of population growth, climate and land use change. Keywords: Water sensitive urban design, water; rooftop rainwater harvesting; surface runoff, stormwater, 40/60 condominium
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    Mapping The Level of Active Frontage in Addis Ababa City, Ethiopia
    (Addis Ababa University, 2025-11-01) Ametu Mohammed Oumer; Tibebu Assefa
    Active frontages have high value for city development. However in Addis Ababa fence properties, blind walls and streets which make its frontage inactive and repressive for citizen, passersby and visitors. Blind walls or street frontages with few openings are deterring. The study aims to measure active frontage level of Addis Ababa city. Active frontage level in Addis Ababa city was identified on field observation and by applying Arc GIS software digitize and give attribute of each frontage level data obtained from field survey,(captured photos in walk-along), analyze, interpret, map out active frontage level map and rated active frontage level. Accordingly the city has been rated frontage level from A to E. Where frontage level A is full of widows and inviting and frontage level E is for passive frontage. The study investigated that the level of active frontage level in Addis Ababa city was depends on street type, building function, fence and building structure. The result showed that 85.6% of AA is passive while 14.4% % is active. The study found that from the total active street segments in Addis Ababa city 55.6% is both side active streets and 44.4% is one side active streets either right or left side. This shows that even the active streets in Addis Ababa city are not fully active. So the responsible body needs to take action by identifying potential active area by issuing relevant regulation and redistributing magnet buildings. Key words: - Active frontage, passive frontage, active frontage level map.
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    Pedestrian Energy Harvesting System from Walkway of
    (EiABC, 2018-08) Brook Workneh ; Tibebu Assefa
    Addis Ababa is a primate city that needs enormous amount of energy to up keep the socioeconomic development. The frequent black out are signs for looking other alternatives of energy. One of the on-site energy alternatives could be harvested from the pedestrian flow in the city. This flow could be used to harvest and augment its energy supply. Thus, in this work a mechanism that utilizes the dense pedestrian flow for energy generation has been sought for and tested at laboratory scale. After analyzing the pedestrian flow at Aratkilo, Piassa and Mexico and determining their number of pedestrian with in a specific set of time or the Pedestrian Level of Service (PLOS), a machine has been constructed. Parts of the selected streets with PLOS level ‘D’ (15-20) pedestrian foot per minute(PF/M) and ‘E’ (20-25 PF/M) were found to be fit for the system Since PLOS of “A”, “B” and “C” are not dense enough and “F” is too congested for the system.. Street vending, street furniture, queuing and platooning affected walking experience and speed of pedestrians as well as the feasibility of the system. The prototype has been tested and modified at the laboratory and the result has shown that an average of 0.21 (p=2.50954E-20) electric volt for the first group with weight range of 49 -78 kg and 0.2 (p= 1.1495E-25) for the second group of weight range of 54-76 kg has been harvested. This work has demonstrated that pedestrian flow in the main and secondary centers of the city if channeled properly could be a good source of on-site renewable energy for a city aspiring to be sustainable. It also indicates the need for integrated urban design solution for urban challenges. .
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    The Influence of Street Pattern Configuration on Road Traffic Accident in the Case of Two Cities: Dilla and Debre Birhan, Ethiopia
    (Addis Ababa University, 2024-06-01) Flagote Taye Yifru; Tibebu Assefa
    The purpose of this study is to find out, whether the variation of street pattern configuration impacts the incidence of Road traffic accident (R.T.A.). Dilla and Debre Birhan cities are selected due to their different street pattern configuration and approximate equal number of population. RTA, in Dilla city is the most common type of injury causes and it is responsible for higher percentage of death among suffering patients. Residents believe that, the cause of this accident is the city’s grid iron street pattern configuration. Debre Birhan in the other hand has mixed street pattern configuration and has relatively lower accident rate. In order to assess the influence, initially, identifying hotspot areas, then analyzing road maps of each city to get data about street configuration parameters, representing hotspots on each cities’ street maps as well as their parametric maps and selecting the most significant parameters to correlating the variables are followed respectively. Street maps of the cities are converted to axial map to analyze the configuration using tool of analysis, called space syntax via software depth map X. This data collaborating with accident risk rate, states their correlation one to another. Consequently, the study provided accident estimation models based on the parameters of street pattern configuration. For Dilla it is explainable by the predictors F (6, 4) = 19.03, p 0.05, R2 = 0.799. Adjusted R value brought the significance level’s explainablity of Dilla’s RTA by parameters to 91.5% and 33% for Debre Birhan. Finally it’s recommended to create awareness about space syntax for those having no prior experience and highlights the importance of considering space syntax while planning and designing road network, is important factor. Key Words: RTA, Space Syntax, Dilla city road network, Debre Birhan city road network.
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    The Policy Paradox of Metropolitan Compact Development: The Historical and Socio-Cultural Dimensions in Addis Ababa’s Modernization
    (Addis Ababa University, 2024-07-01) Matiyas Bekele Fantaye; Tibebu Assefa ; Liku Workalemahu
    The critiques of metropolitan modernization sideline the nexus of the global and national policy constraint for adapting socio-culturally sustainable and land scape based models in the context of capital city planning. Addis Ababa’s context is relevant due to its exemplary historical and contemporary cases: The earlier modernization endeavors fulfilled against the medieval model foundation of the traditional settlement have still continued devoid of a strong moral basis. This doctoral essay aims to argue that the Compact City policy intensified in the last two decades will have dire socio-cultural implications, owing to the city’s radical imagebuilding historical legacy as well as the global pressure. The criticism necessitated to meet three objectives: the first was to elaborate how the medieval traditions by which the city was formed resisted the early modernization trends (Westernization, capitalistic); whereas the second characterized the post-War architectural marvels from the international historical perspective. The third examined the current policy implications in relation to the previous two. For this purpose, a flexible multi-method and multiple case-studies research design was employed to generate the relevant data from primary and secondary sources, including historical documents, city plans, accessible (authoritative) evaluation reports, and site observations. The analogical induction between the main concern of the contemporarily adapted model of sustainability and the motives of the historical modernization policy infer the The Policy Paradox of Metropolitan Compact Development IV problematic position of the diplomatic, capital city, as pressured to ambitiously look modern. In conclusion, such radical urban transformation drives (i.e. city image building obsession devoid of the optimal development rate) will undermine the local community, urban heritage conservation-based development as well as institutional resilience (capacity building). The insight is significant for the debate on the Sub Saharan political economy of metropolitan modernity, suggesting the real intentions of the preference to certain types of ‘sustainability’ strategies, in addition to the predicaments of globalization (late capitalism) for equitable urban transition. Key: Metropolitan Modernization Sustainability, Historical-Institutional Challenges, Socio-Cultural Challenges, Addis Ababa City Plans, Urban Sustainability Models, Compact City Policy, Equitable Urban Transition
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    Urban Water Metabolism for Promoting Water-Sensitive Urban Planning Interventions in Adama City, Ethiopia
    (Addis Ababa University, 2025-01-01) Abraha Tesfay Abraha; Tibebu Assefa
    Urban metabolism quantifies resource flow within urban boundaries focusing on urban water, energy, nutrients and wastes. However, in developing nations,little research has been done to provide a quantitative picture of how water is consumed and transformed in urban landscape, as well as the water sensitive planning interventions needed to improve urban water security. This research was aimed to analyze the urban water metabolism of Adama city, Ethiopia as a foundation for evidence-based decision-making for water sensitive urban planning and enhance urban water security. The study employed a mixed-methods approach combining Material Flow Analysis (MFA) and urban water mass balance to track and trace water inflows, outflows and losses. Geo spatial tools were used to map water supply source locations, distribution networks, consumption patterns and water stress. Water security was quantified using the Integrated Urban Water Security Index (IUWSI). The study applied the Random Forest algorithm in R version 4.0.5. This algorithm was used to identify factors influencing residential water consumption. Key informant interviews and surveys were conducted to collect data on consumption and conservation behaviours across households, commercial, institutional and industrial water users. The data collection was conducted by combining both the bottom-up and top-down data collection systems. Findings indicated that Adama city is located in a water-stressed geographical location that receives less than 1700 m³ of water per person annually. The city's daily per capita water consumption is 69 liters falling short of Ethiopia's standard of 80 liters. The water distribution network covers only 45% of the area outlined in the master plan. The result also indicated a 38% gap between water demand and supply. Furthermore, nearly 30% of households receive water just at most three days a week. The centralized water supply accounts for 61% of the total consumption with 90% sourced from the distant Awash River indicating the city’s dependency on remote sources. Water conservation practices in Adama are limited. This reflects a linear take-make-use-dispose model that overlooks internal alternative water harvesting s. The urban water security index of 1.95 revealed that Adama lacks water sensitive planning and strategies to ensure the urban water security. The study also revealed that key factors influencing water consumption are family size, housing quality, income levels, the number of rooms, parcel legal status, supply reliability, climate and topography. In conclusion, Adama is experiencing significant urban water insecurity due to both economic and physical water scarcity along with limited water-sensitive interventions. Adama city is heavily dependent on a centralized water source which lacks internalization and diversification practices coupled with underdeveloped conservation practices. Another conclusion that can be drawn is that as long as the city’s business as usual water consumption practice doesn’t change, the water supply problem will worsen over time. Hence, to strengthen urban water security, Adama city should implement water-sensitive urban planning interventions and strategies that encompass community engagement, the adoption of water-saving technologies, water-sensitive urban land use planning and the establishment of a robust water sensitive legal framework to promote urban water security. Keywords: Metabolism, water mass balance, water stress, water security, water sensitive, Adama, Ethiopia