Design Of Hydraulic Structures For Sustainable Runoff Control In Kinamba Sub-Catchment, Rwanda

Tharcisse TWIZEYIMANA, Prof. Dr. Muthiah Sankaranarayanan

Abstract


The process of urbanization is among the causes of the continuous increase of flood hazard events and the associated losses worldwide; mainly due to the increasing impervious surfaces and the exposure of people and their wealth. (Muis et al., 2015)  In Rwanda, mainly in Kigali City, heavy rainfall events cause rapid surges in the flow of rivers and drainage systems leading to floods in the downstream. It has been identified that inadequate drainage system in Kinamba sub-catchment located in Nyabugogo catchment is the major cause of flooding in the downstream of that area.The aim of this study was to design hydraulic structures for sustainable runoff control in Kinamba Sub-catchment. Daily rainfall data for 30 years have been collected from Gitega meteorological station. The peak runoff water discharge has been calculated by using the rational method and its prediction in 30 years by using the linear model. In this research ArcGis played a key role while analyzing spatial data.The results showed that the two existing culverts are capable of carrying water discharges at 91.168 m3/ sec while the estimated current peak runoff discharge is 108.73 m3/sec while considering daily maximum rainfall of 98mm. The population growth rate increase compelled to estimate the future area to be covered for facilitating human settlement. It was found that in next 30 years, all easily usable area will be covered by population leaving around 6.5% area. The remaining catchment area would be covered by houses and roads  with a predicted discharge rate of 118.41m3/sec during next 30 years.Based on the needs, a trapezoidal channel of designed 14.27 m2 cross section has been recommended along with a rectangular  box culvert with 6 boxes of 2.8m depth and 2m width with a discharge carrying capacity of 118.41 m3/sec. It is also recommended to have household level water harvesting and management of catchment area by keeping balance in housing and open area while respecting Rwanda housing policy.


Keywords


Sustainable runoff control, Sub-catchment, Hydraulic structures

Full Text:

PDF

References


Apel,H, Thieken,A.H.., Merz,B& Bloschl,G.2004.Flood risk assessment and associated uncertainty. Natural hazards and Earth system sciences. 4, 295-308.

Bizimana J. P; Schilling M.; 2010; Geo-Information Technology for Infrastructural Flood Risk Analysis in Unplanned Settlements: Informal Settlement Flood Risk in the Nyabugogo Flood Plain, Kigali City, Rwanda (6-12).

Bouwer, L. M. 2010. Have Disaster Losses Increased Due to Anthropogenic Climate Change? Bulletin of the American Meteorological Society, 92, 39-46.

Butler, D. and Davies, W.J., 2004. Urban Drainage, 2nd Edition, Spon Press, 11 New Fetter Lane, London.

Chow, V.T., Maidment, D.R. and Mays, L.W., 1988. Applied hydrology, McGraw-Hill, Singapore, (99-126).

CIV 246; 2009; Water resources technology; the elements of hydrology and hydraulic systems, Mountain Empire Community College.

De Laat, P.J.M., Savenije, H.H.G., 2002. Hydrology. Lecture notes. UNESCO-IHE Institute for Water Education, Delft, The Netherlands.

European flood alert system; 2009. Statistical skill assessment of probabilistic and deterministic operational forecasts, 24-26.

HEC 15, April 1988; Design of Roadside Channels with Flexible Lining, Metric Version. (Page: 132).

Hollis, G. E. 1975. Effect of urbanization on floods of different recurrence interval. Water Resources Research, 11, 431-435.

Kirpich, Z.P., 1940. Time of concentration of small agricultural watersheds. Civil Engineering, 10(6), 362. The original source for the Kirpich equation.

Langousis, A., 2005. The Area Reduction Factor (ARF): a multifractal analysis. Massachusetts, Institute of technology, Cambridge.

MIDIMAR; 2012; Identification of disaster higher risk zones on floods and landslides in Rwanda.( 8-9,21-25).

Muis.S.Guneralp,B.., Jongman,B.., Aerts,J.C.J.H&Ward, P.J.2015. Flood risk and adaptation strategies under climate change and urban expansion. A probabilistic analysis using global data. Science of the total environment, 538, 445-457.

Munyaneza o. et al ;2014; Influence of Urbanization on Hydrology and Infrastructure in the Kabuga Town, Rwanda (5,7-9).

Munyaneza O.; 2013), Hydraulic Structures Design for Flood Control in the Nyabugogo Wetland, Rwanda, Nile Basin Water Science & Engineering Journal, Vol.6, Issue 2, 2013 (12-14).

Munyaneza O.; 2014; Space-time variation of hydrological processes and water resources in Rwanda; focus on the Migina catchment; UNESCO-IHE, Institute for Water Education for the Degree of Doctor (27,29,32).

Nhapi; Wali U.G., Uwonkunda B. K., Nsengimana, H., Banadda, N., and Kimwaga, R.; 2011; Assessment of Water Pollution Levels in the Nyabugogo Catchment. (page 41).

Nsengiyumva,J.B.2012.Disaster high risk zones on floods and landslides. Kigali: MIDIMAR.

Olson, N. C., Gulliver, J. S., Nieber, J. L. & Kayhanian, M. 2013. Remediation to improve infiltration into compact soils. Journal of Environmental Management, 117, 85-95.

Randrup, T. B. & Dralle, K. 1997. Influence of planning and design on soil compaction in construction sites. Landscape and Urban Planning, 38, 87-92.

Rick Burnett et al; 2012; California natural resources agency-Department of water resources.( 9-12).

South African National Road Agency; 2013; Drainage manual application guide; sixth edition.(152-158).

USAID; 2011; Flood Control Structures; addressing climate change impact on infrastructure in Iloilo, Philippines.( 1-3).




DOI: http://dx.doi.org/10.52155/ijpsat.v36.2.4969

Refbacks

  • There are currently no refbacks.


Copyright (c) 2023 Tharcisse TWIZEYIMANA, Prof. Dr. Muthiah Sankaranarayanan

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.