Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya

Elizabeth Wambui Nyokabi; Raphael Muli Wambua; Romulus Okoth Okwany

doi:doi:10.11648/j.jccee.20210601.11

| Peer-Reviewed

Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya

Elizabeth Wambui Nyokabi, Raphael Muli Wambua, Romulus Okoth Okwany

Published in Journal of Civil, Construction and Environmental Engineering (Volume 6, Issue 1)

Received: 19 December 2020 Accepted: 28 December 2020 Published: 12 January 2021

Views: Downloads:

Download PDF

Share This Article

Twitter
Linked In
Facebook

Abstract

Appropriate water quality and quantity are critical problem greatly affecting significant proportion of the population particularly those living in semi-arid and arid areas. Rainfall characteristics, streamflow and reservoir levels are some of the key hydro-meteorological variables within a catchment in the determination of sufficiency of water quantity. Lake Naivasha reservoir level continues to be hit by anthropogenic stressors such as loss of wetlands, water abstraction and eutrophication. Also there has been a lot of fluctuation in flow discharge of Malewa River over the years where the tributaries (Turasha and Karati streams) usually dries up during dry season. This paper presents the results of a research to assess the time series trends of rainfall, streamflow and lake basin levels data in the catchment from 1980-2018 using Mann-Kendall trend test to assess water quantity status. Monthly stream flow, rainfall and reservoir level data in the catchment were obtained from Water Resources Management Authority (WRMA) and Kenya Meteorological Department (KMD) for the years 1980-2018. Non-parametric Mann-Kendall rank statistics test was used to examine the trend components of hydro-meteorological variables. The P-values were used to test whether the null hypotheses were statistically significant (α<0.05) at a 5% level of significance. Rainfall values had an increasing trend from 2011 onwards but not statistically significant while annual streamflow values had no trend as P-value showed weak evidences to rejected the null hypothesis. Reservoir level had an upward trend in years 1981, 2001, 2003, 2012 and 2018 while downward trends in 1980, 1982, 1984, 1986, 1987, 2000, 2004, 2008 and 2014. From 2010 onwards, in monthly data, there have been upward water levels in the lake as shown by the trend. These show that the hydro-meteorological indicators in the catchment are independently trending, therefore some other factors such as land cover changes or climate changes were adversely affecting the hydrological cycle. These findings are helpful for planning and management in water resource systems such as forecasting water distribution and mitigate flood and drought.

Published in	Journal of Civil, Construction and Environmental Engineering (Volume 6, Issue 1)
DOI	10.11648/j.jccee.20210601.11
Page(s)	1-8
Creative Commons	This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited.
Copyright	Copyright © The Author(s), 2021. Published by Science Publishing Group

Keywords

Rainfall, Reservoir Level, River Malewa, Streamflow, Trends of Hydro-meteorological Data

References

[1]	Mohammed, G., Denghua, Y., Hao, W., Tianling, Q., Abel, G., Asaminew, A., & Dorjsuren, B. (2018). Innovative Trend Analysis of Annual and Seasonal Rainfall Variability in Amhara Regional State, Ethiopia. Atmosphere, 9 (326). https://doi.org/10.3390/atmos9090326.
[2]	Tosunoglu, F. (2017). Trend Analysis of Daily Maximum Rainfall Series in Çoruh Basin, Çoruh Havza ’ sındaki Günlük Maksimum Yağış Serilerinin Trend Analizi. Iğdır Univ. J. Inst. Sci. & Tech., 7 (1), 195–205.
[3]	Rakonczai, J. (2011). Effects and consequences of global climate change in the Carpathian Basin. In J. Blanco & H. Kheradmad (Eds.), Climate change- Geophysical foundations and ecological affects (Climate ch, pp. 229–232). Intech, Rijeka.
[4]	Njiru, J., Waithaka, E., & Aloo, P. A. (2017). An Overview of the Current Status of Lake Naivasha Fishery: Challenges and Management Strategies. The Open Fish Science Journal, 10 (1), 1–11. https://doi.org/10.2174/1874401x01710010001.
[5]	Cheruiyot, M., Gathuru, G., & Koske, J. (2018). Quantity and Trends in Streamflows of the Malewa River Basin, Kenya. Journal of Environmental Science and Engineering, B (7), 18–27. https://doi.org/10.17265/2162-5263/2018.01.003.
[6]	Becht, R., Odada, E., & Higgins, S. (2005). Lake Naivasha: Experience and Lessons learned. ILEC, 277–298.
[7]	Mwai, M. D. (2011). Effects of Climate Change and Human Activity on Lake Levels in the Kenyan Rift (Case Study Naivasha). University of Nairobi.
[8]	Ruhakana, A. (2016). The Estimation of Lake Naivasha Area Changes Using of Hydro-Geospatial Technologies. Rwanda Journal, 1 (II). https://doi.org/10.4314/rj.v1i2S.3D.
[9]	Moturi, N. F. (2015). A Hydrological Study of the Rising Water Level at Lake Nakuru. University of Nairobi.
[10]	Wanjuhi, D. M. (2016). Assessment of Meteorological Drought Characteristics in North Eastern Counties of Kenya. University of Nairobi, Kenya.
[11]	Mondal, A., Kundu, S., & Mukhopadhyay, A. (2012). Rainfall Trend Analysis by Mann-Kendall Test: a Case Study of North-Eastern part of Cuttack District, Orissa. International Journal of Geology, Earth and Environmental Sciences, 2 (1), 70–78. https://doi.org/ISSN: 2277-2081.
[12]	Wambua, R. M. (2016). Drought Assessment and Forecasting using Indices and Artificial Neural Networks for the Upper Tana River Basin, Kenya. Egerton University.
[13]	Ustaoglu, B. (2012). Trend analysis of annual mean temperature data using mann-kendall rank correlation test in catalca – kocaeli peninsula, northwest of turkey for the period of 1970–2011. IBAC, 2, 276–287.
[14]	Zhang, Y., Cai, W., Chen, Q., Yao, Y., & Liu, K. (2015). Analysis of changes in precipitation and drought in Aksu River Basin, Northwest China. Advances in Meteorology, 2015 (215840), 15. https://doi.org/10.1155/2015/215840.
[15]	Forootan, E. (2019). Analysis of trends of hydrologic and climatic variables. Soil and Water Research, 14 (3), 163–171. https://doi.org/https://doi.org/10.17221/154/2018-SWR.
[16]	Gilbert, R. O. (1987). Statistical Methods for Environmental Pollution Monitoring. Van Nostrand Reinhold Company Inc, 1987.
[17]	Kyambia, M. M., & Mutua, B. M. (2014). Analysis of Drought effect on Annual stream flows of River Malewa in the Lake Naivasha Basin, Kenya. Int J Cur Res Rev, 6 (18), 1–6.
[18]	Mwenda, N. D. (2019). Trend Detection in Precipitation and River Discharge to Assess Climate Change in the Upper Tana Basin (Issue June). University of Nairobi.
[19]	Odongo, V. O. (2016). How climate and land use determine the hydrology of Lake Naivasha Basin [University of Twente]. https://doi.org/10.3990/1.9789036542333.
[20]	Reta, G. L. (2011). Groundwater and Lake Water Balance of Lake Naivasha using 3-D Transient Groundwater Model. University of Twente.
[21]	Awange, J., Forootan, E., Kusche, J., Kiema, J. B., Omondi, P., Heck, B., Fleming, K., Ohanya, S., & Goncalves, R., (2013). Understanding the decline of water storage across the Ramser-Lake Naivasha using satellite-based methods. Advances in Water Resources, 60, 7–23. https://doi.org/10.1016/j.advwatres.2013.07.002.
[22]	Boitt, M. K. (2016). Impacts of Mau Forest Catchment on the Great Rift Valley Lakes in Kenya. Journal of Geoscience and Environment Protection, 4 (May), 137–145. https://doi.org/10.4236/gep.2016.45014.

Cite This Article

Plain Text BibTeX RIS

APA Style

Elizabeth Wambui Nyokabi, Raphael Muli Wambua, Romulus Okoth Okwany. (2021). Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya. Journal of Civil, Construction and Environmental Engineering, 6(1), 1-8. https://doi.org/10.11648/j.jccee.20210601.11

Copy | Download

ACS Style

Elizabeth Wambui Nyokabi; Raphael Muli Wambua; Romulus Okoth Okwany. Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya. J. Civ. Constr. Environ. Eng. 2021, 6(1), 1-8. doi: 10.11648/j.jccee.20210601.11

Copy | Download

AMA Style

Elizabeth Wambui Nyokabi, Raphael Muli Wambua, Romulus Okoth Okwany. Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya. J Civ Constr Environ Eng. 2021;6(1):1-8. doi: 10.11648/j.jccee.20210601.11

Copy | Download

@article{10.11648/j.jccee.20210601.11,
  author = {Elizabeth Wambui Nyokabi and Raphael Muli Wambua and Romulus Okoth Okwany},
  title = {Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya},
  journal = {Journal of Civil, Construction and Environmental Engineering},
  volume = {6},
  number = {1},
  pages = {1-8},
  doi = {10.11648/j.jccee.20210601.11},
  url = {https://doi.org/10.11648/j.jccee.20210601.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.jccee.20210601.11},
  abstract = {Appropriate water quality and quantity are critical problem greatly affecting significant proportion of the population particularly those living in semi-arid and arid areas. Rainfall characteristics, streamflow and reservoir levels are some of the key hydro-meteorological variables within a catchment in the determination of sufficiency of water quantity. Lake Naivasha reservoir level continues to be hit by anthropogenic stressors such as loss of wetlands, water abstraction and eutrophication. Also there has been a lot of fluctuation in flow discharge of Malewa River over the years where the tributaries (Turasha and Karati streams) usually dries up during dry season. This paper presents the results of a research to assess the time series trends of rainfall, streamflow and lake basin levels data in the catchment from 1980-2018 using Mann-Kendall trend test to assess water quantity status. Monthly stream flow, rainfall and reservoir level data in the catchment were obtained from Water Resources Management Authority (WRMA) and Kenya Meteorological Department (KMD) for the years 1980-2018. Non-parametric Mann-Kendall rank statistics test was used to examine the trend components of hydro-meteorological variables. The P-values were used to test whether the null hypotheses were statistically significant (α<0.05) at a 5% level of significance. Rainfall values had an increasing trend from 2011 onwards but not statistically significant while annual streamflow values had no trend as P-value showed weak evidences to rejected the null hypothesis. Reservoir level had an upward trend in years 1981, 2001, 2003, 2012 and 2018 while downward trends in 1980, 1982, 1984, 1986, 1987, 2000, 2004, 2008 and 2014. From 2010 onwards, in monthly data, there have been upward water levels in the lake as shown by the trend. These show that the hydro-meteorological indicators in the catchment are independently trending, therefore some other factors such as land cover changes or climate changes were adversely affecting the hydrological cycle. These findings are helpful for planning and management in water resource systems such as forecasting water distribution and mitigate flood and drought.},
 year = {2021}
}

Copy | Download

TY  - JOUR
T1  - Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya
AU  - Elizabeth Wambui Nyokabi
AU  - Raphael Muli Wambua
AU  - Romulus Okoth Okwany
Y1  - 2021/01/12
PY  - 2021
N1  - https://doi.org/10.11648/j.jccee.20210601.11
DO  - 10.11648/j.jccee.20210601.11
T2  - Journal of Civil, Construction and Environmental Engineering
JF  - Journal of Civil, Construction and Environmental Engineering
JO  - Journal of Civil, Construction and Environmental Engineering
SP  - 1
EP  - 8
PB  - Science Publishing Group
SN  - 2637-3890
UR  - https://doi.org/10.11648/j.jccee.20210601.11
AB  - Appropriate water quality and quantity are critical problem greatly affecting significant proportion of the population particularly those living in semi-arid and arid areas. Rainfall characteristics, streamflow and reservoir levels are some of the key hydro-meteorological variables within a catchment in the determination of sufficiency of water quantity. Lake Naivasha reservoir level continues to be hit by anthropogenic stressors such as loss of wetlands, water abstraction and eutrophication. Also there has been a lot of fluctuation in flow discharge of Malewa River over the years where the tributaries (Turasha and Karati streams) usually dries up during dry season. This paper presents the results of a research to assess the time series trends of rainfall, streamflow and lake basin levels data in the catchment from 1980-2018 using Mann-Kendall trend test to assess water quantity status. Monthly stream flow, rainfall and reservoir level data in the catchment were obtained from Water Resources Management Authority (WRMA) and Kenya Meteorological Department (KMD) for the years 1980-2018. Non-parametric Mann-Kendall rank statistics test was used to examine the trend components of hydro-meteorological variables. The P-values were used to test whether the null hypotheses were statistically significant (α<0.05) at a 5% level of significance. Rainfall values had an increasing trend from 2011 onwards but not statistically significant while annual streamflow values had no trend as P-value showed weak evidences to rejected the null hypothesis. Reservoir level had an upward trend in years 1981, 2001, 2003, 2012 and 2018 while downward trends in 1980, 1982, 1984, 1986, 1987, 2000, 2004, 2008 and 2014. From 2010 onwards, in monthly data, there have been upward water levels in the lake as shown by the trend. These show that the hydro-meteorological indicators in the catchment are independently trending, therefore some other factors such as land cover changes or climate changes were adversely affecting the hydrological cycle. These findings are helpful for planning and management in water resource systems such as forecasting water distribution and mitigate flood and drought.
VL  - 6
IS  - 1
ER  -

Copy | Download

Author Information

Elizabeth Wambui Nyokabi

Department of Agricultural Engineering, Egerton University, Nakuru, Kenya
Raphael Muli Wambua

Department of Agricultural Engineering, Egerton University, Nakuru, Kenya
Romulus Okoth Okwany

Department of Agricultural Engineering, Egerton University, Nakuru, Kenya

Download PDF

Sections

Plain Text BibTeX RIS

APA Style

Elizabeth Wambui Nyokabi, Raphael Muli Wambua, Romulus Okoth Okwany. (2021). Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya. Journal of Civil, Construction and Environmental Engineering, 6(1), 1-8. https://doi.org/10.11648/j.jccee.20210601.11

Copy | Download

ACS Style

Elizabeth Wambui Nyokabi; Raphael Muli Wambua; Romulus Okoth Okwany. Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya. J. Civ. Constr. Environ. Eng. 2021, 6(1), 1-8. doi: 10.11648/j.jccee.20210601.11

Copy | Download

AMA Style

Elizabeth Wambui Nyokabi, Raphael Muli Wambua, Romulus Okoth Okwany. Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya. J Civ Constr Environ Eng. 2021;6(1):1-8. doi: 10.11648/j.jccee.20210601.11

Copy | Download

@article{10.11648/j.jccee.20210601.11,
  author = {Elizabeth Wambui Nyokabi and Raphael Muli Wambua and Romulus Okoth Okwany},
  title = {Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya},
  journal = {Journal of Civil, Construction and Environmental Engineering},
  volume = {6},
  number = {1},
  pages = {1-8},
  doi = {10.11648/j.jccee.20210601.11},
  url = {https://doi.org/10.11648/j.jccee.20210601.11},
  eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.jccee.20210601.11},
  abstract = {Appropriate water quality and quantity are critical problem greatly affecting significant proportion of the population particularly those living in semi-arid and arid areas. Rainfall characteristics, streamflow and reservoir levels are some of the key hydro-meteorological variables within a catchment in the determination of sufficiency of water quantity. Lake Naivasha reservoir level continues to be hit by anthropogenic stressors such as loss of wetlands, water abstraction and eutrophication. Also there has been a lot of fluctuation in flow discharge of Malewa River over the years where the tributaries (Turasha and Karati streams) usually dries up during dry season. This paper presents the results of a research to assess the time series trends of rainfall, streamflow and lake basin levels data in the catchment from 1980-2018 using Mann-Kendall trend test to assess water quantity status. Monthly stream flow, rainfall and reservoir level data in the catchment were obtained from Water Resources Management Authority (WRMA) and Kenya Meteorological Department (KMD) for the years 1980-2018. Non-parametric Mann-Kendall rank statistics test was used to examine the trend components of hydro-meteorological variables. The P-values were used to test whether the null hypotheses were statistically significant (α<0.05) at a 5% level of significance. Rainfall values had an increasing trend from 2011 onwards but not statistically significant while annual streamflow values had no trend as P-value showed weak evidences to rejected the null hypothesis. Reservoir level had an upward trend in years 1981, 2001, 2003, 2012 and 2018 while downward trends in 1980, 1982, 1984, 1986, 1987, 2000, 2004, 2008 and 2014. From 2010 onwards, in monthly data, there have been upward water levels in the lake as shown by the trend. These show that the hydro-meteorological indicators in the catchment are independently trending, therefore some other factors such as land cover changes or climate changes were adversely affecting the hydrological cycle. These findings are helpful for planning and management in water resource systems such as forecasting water distribution and mitigate flood and drought.},
 year = {2021}
}

Copy | Download

TY  - JOUR
T1  - Assessment of Rainfall, Streamflow and Reservoir Level Trends for Malewa River Catchment, Naivasha, Kenya
AU  - Elizabeth Wambui Nyokabi
AU  - Raphael Muli Wambua
AU  - Romulus Okoth Okwany
Y1  - 2021/01/12
PY  - 2021
N1  - https://doi.org/10.11648/j.jccee.20210601.11
DO  - 10.11648/j.jccee.20210601.11
T2  - Journal of Civil, Construction and Environmental Engineering
JF  - Journal of Civil, Construction and Environmental Engineering
JO  - Journal of Civil, Construction and Environmental Engineering
SP  - 1
EP  - 8
PB  - Science Publishing Group
SN  - 2637-3890
UR  - https://doi.org/10.11648/j.jccee.20210601.11
AB  - Appropriate water quality and quantity are critical problem greatly affecting significant proportion of the population particularly those living in semi-arid and arid areas. Rainfall characteristics, streamflow and reservoir levels are some of the key hydro-meteorological variables within a catchment in the determination of sufficiency of water quantity. Lake Naivasha reservoir level continues to be hit by anthropogenic stressors such as loss of wetlands, water abstraction and eutrophication. Also there has been a lot of fluctuation in flow discharge of Malewa River over the years where the tributaries (Turasha and Karati streams) usually dries up during dry season. This paper presents the results of a research to assess the time series trends of rainfall, streamflow and lake basin levels data in the catchment from 1980-2018 using Mann-Kendall trend test to assess water quantity status. Monthly stream flow, rainfall and reservoir level data in the catchment were obtained from Water Resources Management Authority (WRMA) and Kenya Meteorological Department (KMD) for the years 1980-2018. Non-parametric Mann-Kendall rank statistics test was used to examine the trend components of hydro-meteorological variables. The P-values were used to test whether the null hypotheses were statistically significant (α<0.05) at a 5% level of significance. Rainfall values had an increasing trend from 2011 onwards but not statistically significant while annual streamflow values had no trend as P-value showed weak evidences to rejected the null hypothesis. Reservoir level had an upward trend in years 1981, 2001, 2003, 2012 and 2018 while downward trends in 1980, 1982, 1984, 1986, 1987, 2000, 2004, 2008 and 2014. From 2010 onwards, in monthly data, there have been upward water levels in the lake as shown by the trend. These show that the hydro-meteorological indicators in the catchment are independently trending, therefore some other factors such as land cover changes or climate changes were adversely affecting the hydrological cycle. These findings are helpful for planning and management in water resource systems such as forecasting water distribution and mitigate flood and drought.
VL  - 6
IS  - 1
ER  -

Copy | Download