The water quality in eight small reservoirs (0.065-0.249 km2
) in both the rugged
escarpment landscape above the rift valley floor and the stepped plateau above them were studied
between 1998 and 2000. Water transparency was measured using a 20cm Secchi visibility disk. Total
dissolved solids (TDS) and electrical conductivity (specific conductance) with temperature compensation
at 25o
C were recorded in situ from a portable Jenway probe model 4075. Water pH, dissolved oxygen
(DO), percentage oxygen saturation (POS) were recorded on site from a portable WTW probe model
ProfiLine Oxi 197/197-S. The overall range of mean water pH was 7.0 – 8.4 while the overall range
of mean TDS was 29-82 mg/l. The TDS was slightly higher in the plateau reservoirs. The overall range of
specific conductance was 37-101 µS/cm. The range of TDS and specific conductance in the reservoirs
was quite low compared to other reservoirs in Kenya. The mean range of dissolved oxygen and
percentage oxygen saturation was 2.0-7.2 mg/l, 23.4.2-33.6%, respectively. The level of dissolved oxygen
was quite low in most reservoirs with dry season hypolimnial oxygen deficits in some sites and higher
dissolved oxygen content in the more transparent reservoirs. The summary results showed a clear
difference in water quality between the plateau and escarpment reservoirs in the study area. The
water quality in the reservoirs was found to be suitable for domestic and livestock utilization.
However, additional water quality parameters are required to confirm this conclusion. The reservoirs
were found to possess a good potential for multipurpose development.