Assessment of Wastewater Disposal in Runyenjes Town in Embu County

Poor provision of water supply and wastewater management services in Kenya has negatively
affected the economic development of the country by affecting major sectors that include health,
industry, and commerce.
The absence of a sewer system in Runyenjes Town creates a need for assessment of current
consumption rates and wastewaters management methods. The current onsite treatment methods
need to be assessed for safety and capacity to handle the current and future wastewater flows.
The assessment shows that pit latrines; pour flash toilets, septic tanks, cesspits and disposal into
rivers / streams are not adequate in catering for the current and future wastewater flows, of more
than 7000 m3/day. The future wastewater flows will demand better disposal methods in addition
to the ones existing. High levels of organic matter and total coliforms of the effluent disposed
into Kigaritho stream and downstream of the stream show that EMCAs effluent standards, WHO

drinking water standards are being violated on site by the residents using dilution as a method of
wastewater disposal. These forms of violation in addition to the reported cases of amoebic
dysentery prove that the stream/ river water is unsafe for drinking.
The study concludes that the wastewater from Runyenjes town requires some level of
pretreatment before disposal into rivers or streams. The most economically suitable treatment
method was identified as the use of fine and coarse screens for removal of large solid particles
from the wastewater and emptying the effluent from the screening process into a Waste
Stabilization Pond system consisting of an Anaerobic, Facultative, and Maturation ponds. The
treated wastewater is eventually disposed into River Ena.


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